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Home My WebLink About7 - Update on the Water Utility Master Plan CITY OF BOULDER WATER RESOURCES ADVISORY BOARD AGENDA ITEM MEETING DATE: February 24, 2011 AGENDA TITLE: Update on the Water Utility Master Plan PRESENTER: Bob Harberg, Utilities Planning and Project Management Coordinator EXECUTIVE SUMMARY: The Water Utility Master Plan is nearing completion and this agenda item is intended to update the Water Resoures Advisory Board (WRAB) on the progress to date and schedule for completion and final acceptance. Staff began the process of updating the 10-year old Treated Water Master Plan (TWMP) and developing the overarching Water Utility Master Plan (WUMP) in late 2009. The WUMP is intended to encompass the recently completed Source Water Master Plan (2009) and Water Quality Strategic Plan (2009). Currently, the WUMP is organized as follows: • Volume 1 - Executive Summary (not yet completed) • Volume 2 - General Planning Information (updated, see Attachment A) • Volume 3 - Water Quality Strategic Plan (WQSP) (2009) • Volume 4 - Source Water Master Plan (SWMP) (2009) • Volume 5 - Treated Water Master Plan (TWMP) (updated, see Attachment B) • Volume 6 - Consolidated Capital Improvements Plan (not yet completed) At this time, final drafts of Volume 2 - General Planning Information (see Attachment A) and Volume 5 - Treated Water Master Plan (see Attachment B) are available for review. BACKGROUND: In late 2009 a request for proposals was issued and MWH, a consulting engineering firm, was selected by a staff committee to assist with the project and a scope of work was developed (see Attachment C - Scope of Work) The work includes reviewing existing planning documents and studies, updating population projections and updating the TWMP. The TWMP update includes working with the City's hydraulic distribution system model, determining the hydraulic and AGENDA ITEM 4 7 PAGE 1 of 5 treatment capacity of the water treatment plants, identifying deficiencies in treatment and delivery systems, estimating and ranking capital needs across the entire system, evaluating staffing and administrative operations and preparing a master plan document fitting the City's uniform Master Plan components guidance. Master plans provide for services and facilities and establish: • Detailed policies, • Priorities, • Service standards, and • Facility and system needs. The WUMP is intended to fit into the city's business plan model and combine the utility components plans under one document. The city's business plan model is intended to translate broad direction into action. Departments are expected to create current master plans or strategic plans containing key components for the business plan including: • Investment strategies to guide the prioritization of services/programs, • Service standards, and • Three funding plans: fiscally constrained, action, and vision ANALYSIS: Volume 2 - General Planning Information includes the following chapters: 1. Water System Overview 2. Water System History 3. Planning Approach and Assumptions 4. Law, Policies and Goals 5. Water Use 6. Finance and Administration Volume 5 - Treated Water Master Plan includes the following chapters: 1. Introduction 2. Existing Facilites and Resources, including 3. Water Quality Regulations and Goals 4. Treatment and Distribution Facilities Studies 5. Facilities Evaluation 6. Asset Management 7. TWMP Recommendations and Conclusions The information presented in these volumes will be used to develop a prioritized list of capital improvement projects as part of Volume 6 - Consolidated Capital Improvements Plan. The consolidated capital improvements plan is intended to inform the 2012-2017 budget process. AGENDA ITEM 4 7 PAGE 2 of 5 Several key issues have been identified to date: 1. The planning period for the Treated Water Master Plan (TWMP) and Water Utility Master Plan (WUMP) is through the year 2035. Population and employment are anticipated to grow moderately during the time period with multifamily residential customers increasing by 20 percent whereas single family residential customers are only expected to increase by 3 percent. Employment is anticipated to grow by about 20 percent during this same period of time. 2. To estimate current baseline water use, the time period 2006 through 2009 was selected with an average water production of 18,800 acre-feet. This time period was selected because it is very recent and since the net irrigation requirement based on weather conditions during this period was 103 percent of the long-term average. During this time period water production varied from 20,372 acre-feet in 2006 to 17,280 acre-feet in 2009. Water production did not trend exactly with the net irrigation requirements, which varied from 88 percent of the 2006-2009 average in 2009 to 117 percent of average in 2007. 3. The drought of 2002 was the most severe single drought year in three hundred years. The drought resulted in mandatory water use restrictions in the city that caused annual water use to drop by 20 percent. Current water use continues to be lower than prior to the 2002 drought even though population and employment has grown slightly. Unit demand factors for various customer categories are now mostly consistent with the water conservation goals established by City Council in 2000. 4. Projected water usage is based on historical water usage, future population and employment estimates, projected land uses from the Comprensive Plan and the conservation goals adopted by City Council in 2000. As a result, treated water demand is estimated to increase about 13 percent by 2035 compared to the baseline water use (2006-2009.) Although additional reduction in these demand factors may be realized in the future due to conservation efforts, there may also be upward pressure on future irrigation demands if climate change raises average temperatures. Therefore, it has been assumed that the demand factors based on this approach used in the WUMP are suitably conservative for planning purposes. 5. Based on the reductions in water use since setting sector specific water use goals in 2000 and the ability of the City to meet current and future water use demands, the focus of the Water Conservation Program over the next 10 year planning horizon was evaluated. An overarching goal for future Water Conservation Program efforts is to tailor water conservation to the city's unique water system, focus on the nexus between water and energy conservation, and to support water- related environmental enhancements. To meet future needs, current water conservation programs will be evaluated and aligned with Water Conservation Program goals. On a planning level this will include enhancing Water Conservation Program support for balancing the amount of west slope water AGENDA ITEM 4 7 PAGE 3 of 5 supplied through the Colorado Big Thompson and Windy Gap projects with strategic use of native Boulder Creek basin supplies. This strategic balancing can minimize energy-intensive west slope to east slope water transfers, conserve west slope water, maintain adequate reserves of east slope supplies to meet reliability criteria, and maximize generation of hydroelectric power throughout the city's system. Water conservation measures can be tailored to support water use methods and timing that enhance recharge of local aquifers during high streamflow periods such that delayed return flows can enhance instream flows and reduce seniority of water rights calls. Future water conservation measures should be tailored to Boulder's needs based on the specifics of the city's water rights, structure of the raw water system and location of water treatment facilities rather than be based on generalized concepts of water conservation that may not be as beneficial for Boulder. 6. The analysis performed in the development of the TWMP indicates that the City's existing treated water infrastructure should be adequate to meet water demand needs well into the future. Previously, it was envisioned that large capital funding ($8-9M) would be required at the Betasso Water Treatment Facility (WTF) to retrofit the existing coagulation and sedimentation process with newer technology that would allow the plant to meet current drinking water regulations when operating at its original design capacity of 46 million gallons per day (mgd). This approach was based on a previous evaluation and reports from plant operations personnel of treatment problems at plant flows exceeding 35 mgd. The funding had been scheduled for the 2015-2016 time period. However, because of decreased water use since 2002, the retrofit of the coagulation and sedimentation process should not be needed for another 10-15 years. 7. A comprehensive asset management analysis was performed as part of the development of the TWMP. One of the most significant near term issues is the aging mechanical and electrical equipment at the Betasso WTF. The Betasso WTF is the city's primary water treatment facility and has deteriorated during almost 50 years of operation despite on-going maintenance. It is recommended that large capital funding ($10-16M) be allocated in the 2015-2020 time period to address these needs. These issues and others will be summarized as part of the Volume 1 - Executive Summary and presented to the WRAB for consideration in April. NEXT STEPS: The following schedule for completing the WUMP is currently anticipated: Complete Final Draft of the WUMP March WRAB Update April WRAB Recommendation May Planning Board Recommendation June City Council Acceptance August - September AGENDA ITEM 4 7 PAGE 4 of 5 ATTACHMENTS: Attachment A: Volume 2 - General Planning Information Attachment B: Volume 5 - Treated Water Master Plan (TWMP) Attachment C: MWH Scope of Work AGENDA ITEM 4 7 PAGE 5 of 5 PREPARED FOR CITY OF BONDER General Planning Information FEBRUARY 2011 f L ~ s k"s f* y # ti - wt P poor A + ~ i^r . 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K` w TIW- 1 s VOLUME r*r~ City of Boulder Water Utility Master Plan February 2011 FINAL DRAFT MWH® City of Boulder Final Water Utility Master Plan (February 2011) Page i Table of Contents 1 Water System Overview ..................................................................................................................1-1 1.1 Source Water ..........................................................................................................................1-2 1.2 Water Treatment---------------------------------------------------------------------------------------------------------------------1-2 1.3 Distribution System-----------------------------------------------------------------------------------------------------------------1-3 1.4 Water System Inventory 1-4 1.5 Large Water Users and Private Water Systems .....................................................................1-7 2 Water System History ......................................................................................................................2-1 2.1 Water System History Prior to 2000 .......................................................................................2-1 2.1.1 1875 to 1900; A Period of Supply Development .......................................................2-1 2.1.2 1900 to 1922; Talk of Conservation, Supply, and Energy Development ..................2-2 2.1.3 1922 to 1955 - Water Rights and the Great Depression ...........................................2-3 2.1.4 1959 to 2000; Growth Management, Metering, and Treatment 2-4 2.2 Water System History Update (Since 2000) ...........................................................................2-5 2.2.1 Source Water 2-5 2.2.2 Water Treatment Facilities.. - 2-6 2.2.3 Treated Water Distribution System ...........................................................................2-7 3 Planning Approach and Assumptions ...........................................................................................3-1 3.1 Study Area 3-1 3.1.1 Population and Employment--------------------------------------------------------------------------------------3-1 3.2 Land Use ................................................................................................................................3-2 4 Laws, Policies, and Goals ...............................................................................................................4-1 4.1 Federal and State Laws----------------------------------------------------------------------------------------------------------4-1 4.1.1 Safe Drinking Water Act ............................................................................................4-1 4.1.2 CDPHE Safe Drinking Water Program 4-2 4.1.3 Colorado Water Law--------------------------------------------------------------------------------------------------4-3 4.2 State Constitution and City Code ...........................................................................................4-3 4.3 Boulder Valley Comprehensive Plan 4-4 4.3.1 BVCP Urban Service Standards ...............................................................................4-6 4.4 Utilities Division Mission and Guiding Principles ....................................................................4-7 City of Boulder Final Water Utility Master Plan (February 2011) Page ii 4.5 Reliability Criteria------ ------------------------------------4-8 4.6 Goals --------------------------------------------------------------------------------------------------------------------------------------4-9 4.6.1 Overall Water Utility Goals 4-9 4.6.2 Source Water Goals ------------------------------------------------------------------------------------------------4-10 4.6.3 Water Treatment Goals -------------------------------------------------------------------------------------------4-11 4.6.4 Distribution System Goals 4-11 4.7 City of Boulder Design and Construction Standards 4-11 4.8 Additional Master Plan Design Criteria .................................................................................4-11 4.8.1 Source Water System ..............................................................................................4-11 4.8.2 Water Treatment Plants ...........................................................................................4-13 4.8.3 Hydro Facilities--------------------------------------------------------------------------------------------------------4-14 4.8.4 Distribution System Capacity and Pressure ..4-14 4.8.5 Treated Water Storage ............................................................................................4-15 4.8.6 Treated Water Storage Operating Criteria ..............................................................4-15 4.8.7 Fire Flow and Hydrant Requirements ......................................................................4-15 4.8.8 Pressure Reducing Stations 4-16 4.8.9 Distribution System Mains and Valves ....................................................................4-16 4.8.10 Pumping Capacity ---------------------------------------------------------------------------------------------------4-17 5 Water Use ..........................................................................................................................................5-1 5.1 Historical Water Use---------------------------------------------------------------------------------------------------------------5-1 5.2 Baseline Water Use (1994 to 1996) ---------------------------------------------------------------------------------------5-2 5.3 Current Water Use ........................................................5-3 5.4 Projected Water Use 5-4 5.5 Peaking Factors----------------------------------------------------------------------------------------------------------------------5-6 5.5.1 Peak Month ........................................................5-6 5.5.2 Peak Day.... 5-7 5.5.3 Peak Hour------------------------------------------------------------------------------------------------------------------5-9 5.5.4 Summary of Planning Period Peaking Factors and Flows 5-9 5.6 Water Conservation Program.. - - 5-10 5.6.1 Overview------------------------------------------------------------------------------------------------------------------5-10 5.6.2 City of Boulder Water Conservation Limitations ......................................................5-11 City of Boulder Final Water Utility Master Plan (February 2011) Page iii 5.6.3 Water Conservation Futures Study .........................................................................5-11 5.6.4 Water Savings Goals By Sector ..............................................................................5-11 5.6.5 Water Budget Rate Structure ......................................................5-12 5.6.6 Water Conservation Plan-----------------------------------------------------------------------------------------5-12 5.6.7 Current Water Conservation Program Efforts .........................................................5-12 5.6.8 Water Conservation Accomplishments ...................................................................5-15 5.6.9 Water Conservation Program Recommendations 5-16 6 Finance and Administration ............................................................................................................6-1 6.1 Sources of Funds 6-1 6.1.1 Monthly User Charges ...............................................................................................6-1 6.1.2 Plant Investment Fees-----------------------------------------------------------------------------------------------6-2 6.1.3 Other Revenue Sources 6-3 6.1.4 Comprehensive Rate Study Updates 6-3 6.2 Administration -------------------------------------------------------------------------------------------------------------------------6-3 6.2.1 Organizational Structure--------------------------------------------------------------------------------------------6-3 6.2.2 Enterprise Status .......................................................................................................6-1 6.2.3 Use of Funds -------------------------------------------------------------------------------------------------------------6-1 6.2.4 Asset Valuation----------------------------------------------------------------------------------------------------------6-1 6.2.5 Budgeting and Accounting .........................................................................................6-2 6.2.6 Yearly Audit ---------------------------------------------------------------------------------------------------------------6-3 6.2.7 Revenue Bonds---------------------------------------------------------------------------------------------------------6-3 6.2.8 Reserve Policies 6-3 6.2.9 AWWA Performance Indicators/Benchmarks 6-4 6.3 Metering and Billing ----------------------------------------------------------------------------------------------------------------6-5 6.3.1 Metering 6-5 6.3.2 Billing 6-5 City of Boulder Final Water Utility Master Plan (February 2011) Page iv List of Tables Table 1-1. Source Water Storage ......................................................................................................1-4 Table 1-2. Source Water Conveyance---------------------------------------------------------- ------------------------------------1-6 Table 1-3. Water Treatment Facilities ......................................................................................1-6 Table 1-4. Treated Water Distribution System Pump Stations ..........................................................1-6 Table 1-5. Treated Water Storage Tanks 1-7 Table 1-6. Hydroelectric Facilities------------------------------------------------------------------------------------------------------1-7 Table 3-1. Summary of Planning Population and Employment 3-2 Table 3-2. Summary of Population and Employment by Subcommunity - Current and Projected ...3-2 Table 4-1. Fire Flow Requirements Breakdown ...............................................................................4-16 Table 5-1. Baseline Water Usage from Water Conservation Futures Study 5-2 Table 5-2. Historic Water Usage - 2006 through 2009 and Period Average (Acre-Feet per Year).. 5-3 Table 5-3. Current Water Usage Based on ET-Adjusted Average of 2006 through 2009 .................5-4 Table 5-4. Baseline and Current Water Usage Compared to Conservation Goals (gallons per unit per day) -----------------------------------------------------------------------------------------------------------------------------------5-4 Table 5-5. Planning Water Usage------------------------------------------------------------------------------------------------------5-5 Table 5-6. Planning Period Peaking Factors 5-10 Table 5-7. Planning Period Flows----------------------------------------------------------------------------------------------------5-10 Table 5-8. Baseline and Current Water Usage Compared to Conservation Goals (gallons per unit per day) 5-15 Table 5-9. Water Conservation Rebate Program Summary - 2000 through 2009 ............................5-2 Table 6-1. Water Quantity Charges - Block Rate Structure ...............................................................6-2 Table 6-2. Asset Valuation of the City's Water Utility 6-1 Table 6-3. PIF Unit Costs-------------------------------------------------------------------------------------------------------------------6-2 Table 6-4. Outstanding Bonds ...........................................................................................................6-3 City of Boulder Final Water Utility Master Plan (February 2011) Page v List of Figures Figure 1-1. Utilities Division Organization Chart .................................................................................1-1 Figure 1-3. Betasso WTF --------------------------------------------------------------------------------------------------------------------1-3 Figure 1-6. Recent Annual Water Use of Top Five Water Users 1-8 Figure 1-7. Current Municipal Water Use by Department ...................................................................1-8 Figure 5-1. Long-term Trend in Total Water Use, 1971-2009 5-1 Figure 5-2. Long-term Trend in Outdoor Water Use and Net Irrigation Requirement .........................5-2 Figure 5-3. Historic Water Usage - 2006 through 2009 and Period Average ....................................5-3 Figure 5-4. Planning Water Usage------------------------------------------------------------------------------------------------------5-5 Figure 5-5. Recent Historical Ratio of Peak Month to Average Day Demand ....................................5-7 Figure 5-6. Long-Term Trend in Peak Day Water Usage, 1971-2009 ................................................5-8 Figure 5-7. Recent Historical Ratio of Peak Day to Average Day Demand ........................................5-8 Figure 5-8. Water Usage Diurnal Curve ..............................................................................................5-9 Figure 6-1. Average 2006-2009 Sources of Funds ($26,828,674) .....................................................6-1 Figure 6-2. Number and Percent of Water Customers by Customer Class ........................................6-2 Figure 6-3. Public Works Department Organization Structure ............................................................6-1 Figure 6-4. Average 2006-2009 Uses of Funds ($27,469,536) 6-1 List of Maps Map 1. Water Utility Planning Area Boundary and BVCP Area Boundaries ..............................................1-9 Map 2. Current Land Use ...........................................................................................................................3-3 List of Appendices Appendix A.- Recommended Practices to Meet Goals A-1 1 Water System Overview The Utilities Division of the Public Works Department provides water, sewer and stormwater services. The city operates the three systems as individual "enterprises" Designated enterprise funds are mostly exempt from the revenue constraints imposed by Colorado's Taxpayer's Bill of Rights (TABOR). The city's utilities department is organized as shown in Figure 1-1. The Water Utility Master Plan (WUMP) covers areas including water resources, environmental quality, water treatment and distribution, and system maintenance. The Water Resources Advisory Board (WRAB) is an advisory board to city council and works with staff on water-related issues including reviewing and providing recommendations on master plans, policies, programs, and capital improvements. Utilities Division Master Plans require Planning Board and City Council approval. Figure 1-1. Utilities Division, on Chart Planning Board PublicWork-I Planning & Project Management Water Water I Wastewate Resources Treatmen IM Treatment The physical facilities of the water system are described below in terms of source water, water treatment, and distribution system components. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 1-1 1.1 Source Water The city gets its water from sources on the East Slope and West Slope as follows: • East Slope supplies are primarily from the Boulder Creek Basin. The system includes about 7,200 acre-feet of reservoir storage space in the Silver Lake Watershed on North Boulder Creek and 11,686 acre-feet of storage in Barker Reservoir on Middle Boulder Creek. Most Boulder Creek basin supplies are delivered to the Betasso Water Treatment Facility (WTF) through the Barker system pipelines, the Silver Lake Pipeline and the Lakewood Pipeline. Water can also be delivered from Boulder Creek through Farmers Ditch to the Boulder Reservoir WTF. • West Slope supplies are delivered through the Colorado-Big Thompson (C-BT) Project and Windy Gap Project, which are both operated by the Northern Colorado Water Conservancy District (NCWCD). Boulder receives western slope water at the Boulder Reservoir WTF via C-BT facilities including Carter Lake and the Boulder Feeder Canal. At present, West Slope deliveries to Boulder can only be made from April through October of each year due to winter operating limitations on canals. West Slope deliveries that are not used directly from the canal can be stored within the city's 8,500 acre-feet in Boulder Reservoir or exchanged for additional storage or diversions at the City's upper Boulder Creek facilities. The CBT system also delivers a small amount of water to Boulder from St. Vrain Creek as an exchange with Left Hand Water District. Flows in the watershed basins supplying each source are highly variable from year to year. Because of this, the amount of water derived from each of Boulder's water sources and delivered into the municipal system also varies. The city operates four hydroelectric plants (hydros) on raw water transmission pipelines: Lakewood, Betasso, Boulder Canyon, and Silver Lake. Four additional hydros are on treated water pipelines: Orodell, Sunshine, Kohler, and Maxwell.. Electricity generated at these plants is sold to Xcel Energy. The source water facilities are shown in relation to the city in Figure 4-6 of the SWMP. 1.2 Water Treatment The City's water is treated at the Betasso and Boulder Reservoir water treatment facilities. The Betasso WTF, located west of the city near Sugarloaf Mountain, was originally constructed in 1964. The Betasso WTF has since been upgraded and has a design capacity of about 46 million gallons per day (MGD) with an operational limitation of approximately 32 MGD. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 1-2 The location of the Betasso WTF on a hilltop, see Figure 1-3, limits opportunity for expansion. L A ~y F The Boulder Reservoir WTF was originally constructed in 1971 to provide summer peaking capacity and to treat water from the C-BT and Windy Gap projects. It is now operated year-round and has a firm capacity of about 16 MGD. The facility can treat water from the Boulder Feeder Canal or from Boulder Reservoir. 1.3 Distribution System The water distribution system services areas with elevations ranging from 5,750 feet on the west side of the City to 5,150 feet in the eastern section. Due to this large elevation differential, the system is divided into three pressure zones to keep water pressures within practical limits. Zone 1 serves areas generally below an elevation of 5,270 feet, Zone 2 serves areas between 5,270 and 5,450 feet and Zone 3 serves areas above an elevation of 5,450 feet. Excess water pressure that develops in each zone as water is delivered from the Betasso WTF is reduced by pressure reducing valves and four small hydroelectric facilities. The power that is generated is sold to Xcel Energy. Water from the Boulder Reservoir WTF is pumped to Zone 1 and can be delivered to Zones 2 and Zone 3 by pump stations. The water distribution system consists of a grid of approximately 458 miles of interconnected mains varying in size from 4 to 30 inches. The city operates six covered tanks, ranging in capacity from 2.0 million gallons (MG) to 9.5 MG, with a total storage capacity of 38.9 MG. There is also a clearwell at each of the treatment facilities. There are seven pressure-regulating stations in the system that regulate pressure and flow between pressure zones or into storage tanks. There are four booster pumping stations in the system, as well as a pumping station at the Boulder Reservoir WTF. These booster pumping stations are able to pump water City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 1-3 from a lower elevation pressure zone into a higher elevation pressure zone (see Section 1.4 for additional details). The city operates four hydroelectric facilities on treated water transmission lines at locations that also have parallel pressure-reducing valves: Orodell, Sunshine, Maxwell, and Kohler (see Section 1.4 for additional details). Contracts for the sale of power from these facilities to Xcel Energy are described in Section 3 of the SWMP. Map 1 shows the water utility planning area boundary, pressure zone boundaries and the location of important water system features. 1.4 Water System Inventory Table 1-1 through Table 1-6 provides brief informational summaries of the city's water utility facilities. c)urce Water Storag~- Reservoir River Basin Estimated Storage (AF) Skyscraper Middle Boulder Creek 146 (drought reserve) Barker Reservoir Middle Boulder Creek 11,686 Kossler Reservoir Middle Boulder Creek 165 Green Lake 1 88 (active operating capacity) Green Lake 2 333 (design capacity, pending repairs) Green Lake 3 North Boulder Creek 285 (active operating capacity) Green Lake 4 116.1 (decreed) Green Lake 5 73.8 (decreed) Albion Lake North Boulder Creek 1,111 (capacity) Silver Lake North Boulder Creek 3,996 (active operating capacity) Island Lake North Boulder Creek 333 (active operating capacity) Goose Lake North Boulder Creek 900 (active operating capacity) Lakewood Reservoir North Boulder Creek 35 Colorado River from CBT and Windy Gap storage shared with NCWCD, Boulder's share is Boulder Reservoir projects, St. Vrain Creek, main Boulder Creek 8,500 in winter and 5,143 in summer; total capacity of 13,100 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 1-4 y s+ 8 Xmarai Re Boulder Reservoir' WTP _ - - .aa.gw Ra_ 6 BOOTON EL O O Y--Ar Jay Rd ra Iris Pump K 1 MAXW i.tlaPa.tl.a~a , , a.poaai r a X. Ar ~ 1 ~ ___J~ vaima ~M v.mwmRe Paew'oae or _ !v.,mam Re Ralsam AV d^• ~ I- ~ S suruhyy camm~ Betas- s paae St rl A p1M S 9 To Betasso- PAS ~ WTP - GsaY~a~+~ E y, i AraPaM1Oa AV b fi ~ Arapalae Av - ( l1~IVeraeY A. 1,J coloratlo ~.v, ~ "g &asrGeR_R4_.. _ _ `J Rauline Re ~1Cherryvale Pump CHAUTAUQ S O - T yN_ l\ Sautft BOUWer Rd Bouts 9oukar Rd lfWa Maaa U cr.aaeaar Ri _ _ ~y x ~Je DEVILS C, M~.nau Rd THUMB Legend N O Tanks BVCP Area Boundaries Water Pressure Zones n O Pumps Area 1 F =Zone 1 N Water Treatment Plants Area 11 Zone 2 Water Utility Planning Pipes, 12 inches or greater Area III Zone 3 Water Utility Study Area Boundary and 0 Area Boundary BVCP Area Boundaries MLNH , 2 Miles Map l Table 1-2, Source Water Conveyance Pipeline Source Termination Comments Silver Lake Pipeline North Boulder Creek Lakewood Reservoir 3.5 miles, replaced in 1997, 27-in diameter, and Silver Lake Hydro nominal capacity 20 MGD North Boulder Creek 11 miles, replaced in 3 sections from 1994 Lakewood Pipeline through Lakewood Betasso WTF and through 2004, 27 to 36-inch diameter, design Lakewood Hydro flow of 20 MGD (30 MGD emergency), Phase III Reservoir section has weld defects 12 miles, 36-inch diameter, capacity of 43 cfs, Barker Gravity Line Barker Reservoir Kossler Reservoir originally constructed in 1909; purchased in 2001, ongoing repair of sections Boulder Canyon Boulder Canyon Hydro Penstock Kossler Reservoir Hydro (BCH) 44 to 56-inches diameter, constructed in 1909 Boulder Canyon Betasso Hydro and Betasso Penstock Hydro Penstock Betasso WTF Replaced 2009 with 30-inch diameter pipeline upstream of BCH Boulder Reservoir and Boulder Feeder Canal Carter Lake intake pipeline to 200 cfs (NCWCD) Boulder Reservoir capacity, operated by NCWCD WTF Process Betasso Boulder Reservoir Raw water Lakewood intake (Lakewood Hydro) Reservoir intake (pumps) Barker intake (Betasso Hydro) Boulder feeder canal intake Settling 4 x flocculation/sedimentation basins 3 DAF units Filtration 8 x mixed media filters 4 x mixed media filters Clearwells 2 1 Residuals storage 2 x residuals lagoons 4 x residuals lagoons 2 x residuals drying beds Number of Facility Pumps Pump Information Boulder Reservoir High Service 6 250 hp, 2,800 gpm Iris #1 2 Peerless (6AE18) 150 hp 2,200 gpm @ 205 ft Horizontal Mounted Axial Split Case Single Stage Double Suction Pump Iris #2 2 Cherryvale 3 Aurora Pump Centrifugal 125 hp; 1750 gpm @ 185 ft City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 1-6 Table 1-5. Treated Water Storage Tanks Facility Capacity (MG) Material Gunbarrel 2.0 Steel Maxwell 9.5 Concrete Booton 3.5 Concrete Devil's Thumb 5.0 Steel Kohler 9.4 Concrete Chautauqua 8.0 Concrete Table 1 ydroelectric Facilitie Facility Pressure Source Nameplate Capacity (kW) Maxwell Treated Water (zone 3 to zone 2) 95 Kohler Treated Water (zone 3 to zone 2) 150 Orodell Treated Water (Orodell Pipeline) 225 Sunshine Treated Water (Sunshine Pipeline) 800 Betasso Raw Water (Betasso Penstock) 3,100 Silver Lake Raw Water (Silver Lake Pipeline) 3,309 Boulder Canyon Raw Water (Boulder Canyon Penstock) 10,000 Lakewood Raw Water (Lakewood Pipeline) 3,695 1.5 Large Water Users and Private Water Systems A number of private water systems are connected to the city's treated water distribution system. These systems serve large institutions, commercial or industrial installations, and certain residential areas. The systems are privately owned, operated and maintained. The city provides water to one or more connection points on the private system and the system owner has the responsibility for delivering the water to the end users. Water delivery to the system is metered and the system owner is billed by the city as a single customer. The top four largest water users consistently include the University of Colorado, the City of Boulder, IBM, and Boulder Valley Schools. There are a few entities that have recently been the fifth top water user including the National Institute of Standards (NIST), Boulder Housing Partners, and Countryside Village, a mobile home community. Figure 1-6 depicts the recent historical water usage of the top five water users. Total water use by these large water users decreased between 2006 and 2009. City of Boulder Final Draft Water Utility Master Plan (February 2011) Pagel-7 Fig ht Annual Water Use of Ton Five Water Users 1,000 ■ University of Colorado 900 0 M 800 ■ Cityof Boulder o 700 E 600 W 500 International Business - Ei Machines Corp (IBM) 400 d 300 ■ Boulder Valley Schools 3 200 c a 100 Various: NIST, 0 Countryside Village, or 2006 2007 2008 2009 Boulder Housing Partners Municipal water use was further broken out by department, as shown in Figure 1-7. The greatest water use was for Parks and Recreation, followed by Transportation. Municipal water usage, which is primarily for irrigation, trended with the plant water needs, which was greatest in 2007 based on the weather. Fi 1,000 - Transportation 900 Utilities 800 Police Department a) 700 - ■ Parks Non-irrigation ~ 600 -L~ Parks Community Gardens Q ■ Parks & Rec °J 500 - ® Open Space &Mountain Parks 400 - Library 3 300 = s Hydro Plant a 200 - ■Housing&HumanServices M 100 L Fire Department 0 ■ FAM 2006 2007 2008 2009 ■ Airport There are a couple of wholesale water customers who are charged a flat rate for water. The Lefthand Water District supplies water to large rural areas of Boulder County to the north and northeast of Boulder. Almost all of Lefthand's water supply comes from its own sources and treatment facility, but it has interconnects and a wholesale customer agreement with the city. The Hoover Hills Water and Sewer District serves a residential area located in southeast Boulder north of Baseline Reservoir and east of Cherryvale Road. There are three mobile home parks considered wholesale customers: Boulder Meadows (a.k.a. Countryside Village), Orchard Grove and Mapleton. There are two water truck providers, A-1 Discount Water and Mile Hi Water. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 1-8 2 Water System History The most recent overarching water utility master plan was completed in 1992. A Treated Water Master Plan (TWMP) was completed in 2000; and then in 2009 both a Water Quality Strategic Plan and SWMP were completed. The WUMP updates the 2000 TWMP and incorporates the more recent Water Quality Strategic Plan and SWMP in their entirety as separate volumes. The history of the city's water system has been extensively documented in several previous studies, most recently in the 2000 TWMP and 2009 SWMP. Section 2.1 contains a summary of the water system history through 2000 as documented in the TWMP. Section 2.2 summarizes system changes that have occurred since 2000. Relevant treatment and distribution planning studies completed since 2000 for the water utility are summarized in Volume 5. 2.1 Water System History Prior to 2000 The following water system history information is from the 2000 TWMP' and provides an overview of the entire water utility development up to the year 2000. Development of the water city's system began in the mid-1870s, with the completion of the Town of Boulder Reservoir and its upstream sand filter. Both reservoir and filter were located at the mouth of Boulder Canyon, southwest of Red Rocks on what was then known as the Fox Farm. After the Town of Boulder Reservoir was built, the city began further development of its water distribution network. Pipe was first laid to Twelfth Street (Broadway), then down to the public square where many Boulder residents got their water. The network was also extended to schools and other public buildings and enabled the installation of fireplugs. The key issue in the late 1800s was supply. In 1879, the Town of Boulder Reservoir was considered inadequate for the city's growing needs and the citizens demanded and received an enlarged reservoir. Problems with this source included murky water and insufficient quantity of supply for watering lawns during dry periods. After ten years of use, the reservoir had become totally inadequate. In 1887, excavation began on the new Sunshine Reservoir, located near the base of Sunshine Canyon on Gallup Ranch land. It was designed to hold five million gallons (mg) of runoff water, thus eliminating the need for Town of Boulder Reservoir water. Continued population growth however, necessitated that the old Town of Boulder Reservoir be reactivated. Again, there were complaints of murky water. The Water Superintendent's solution was to use Sunshine Reservoir water during the day when the customers could see it and then use Boulder Reservoir water at night when they could not. Less than a decade later, in 1898, another reservoir at the south end of town was needed, and by 1902 the first Chautauqua Reservoir was completed. This facility should not be confused with the present Chautauqua Reservoir built in 1922. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-1 In 1902, water use was restricted due to drought conditions. Water-powered motors in printing plants and other industries were shut down, and other heavy water users were told to conserve. In 1904, engineers called for the metering of water both to conserve supplies and to sell "the rents" at a fairer rate, but nothing was immediately done. It was not until 1908 that the Colorado and Southern Railroad became the first business to be metered because of its extensive water use. Two years later, the Central Colorado Power Company and larger dairies were metering for the same reason. Not all businesses and institutions were required to be metered. The City Council decided that a cement plant would be accorded a flat rate, and the newly opened Hotel Boulderado would receive free water to encourage tourists to sample Boulder's "famous" water. In 1918, a $20,000 deficit in "water rents" necessitated more industries to be metered. As a result of the increased metering, a $30,000 profit was realized the next year. In January 1904, the city purchased its first parcels of land in the Silver Lake Watershed, which contained the Triple Lakes and Oval Lake. In 1906, the city purchased the land at Albion Lake. The city also purchased the land and reservoirs at Silver Lake and Island Lake, which had been created by dams built by J.P. Maxwell for the Silver Lake Ditch & Reservoir Company in 1887 and 1890, respectively. Boulder bought a large parcel of land in the Silver Lake Watershed from the United States Government in 1907 after receiving permission to do so in the form of a Congressional Grant. Through this first of three Congressional Grants, the city purchased 2,600 acres, which included land near Albion Lake and the Green Lakes on Albion Creek and land on North Boulder Creek. The earthen dam at Oval Lake was replaced in 1908 with a rock-fill timber-crib structure, 30 feet high, to hold 55 million-gallons of water in the enlarged reservoir now called Goose Lake. -Construction of a dam to enlarge Albion Lake was started in 1911 and completed in 1913. In order to protect the water supplies derived from the city's newly-acquired lands and reservoirs in the Silver Lake Watershed, the city decided to build pipelines to prevent contamination as the water was delivered into Boulder. In 1906, the city constructed the Boulder City Pipeline with an intake from North Boulder Creek at the newly-constructed Lakewood Reservoir north of Nederland. The upper portion of this pipeline would later be called the Lakewood Pipeline. The city discontinued most use of the Lower Intake near the mouth of Boulder Canyon. In 1910, the Central Colorado Power Company completed construction of Barker Dam on the Middle Boulder, east of Nederland. The power utility conveyed Barker Dam water through the Barker Gravity Pipeline to Kossler Lake, then by penstock to Boulder Canyon Hydro, located at Orodell across from the city's Lower Intake. The Boulder Canyon Hydro powerhouse , comprised of two generators capable of producing 10,000 kilowatts of power, provided the first electricity for Boulder and much of the surrounding Front Range area. After several mergers, ownership of Boulder Canyon Hydro transferred to Public Service Company of Colorado in 1924. By World War I, Boulder's water supply was thought to be polluted with tungsten material and human wastes necessitating, for the first time, chemical treatment. In 1917, a plant was built at Lakewood to treat Boulder water with chlorine and ammonium sulfate. The treatment method was crude, and chemicals were dumped into the water supply at irregular seasonal intervals. In order to further protect the water from pollution, the city approached its congressional delegation about additional purchases of federal land. A second Congressional Grant, which allowed the city to purchase land below Silver Lake, was approved in 1919. The city constructed an extension of the Boulder City Pipeline, which was later named the Silver Lake Pipeline, running from a point on North Boulder Creek at the eastern edge of the Silver Lake Watershed to Lakewood Reservoir. In 1922, the Chautauqua Reservoir was considered too low and the new Chautauqua Reservoir was built. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-2 In the early 1900s, the City Council had first discussed purchasing land from the United States government in the Silver Lake Watershed up to the Continental Divide and including Arapaho Glacier. In 1927, the U.S. Congress approved the third and final Congressional Grant allowing the city to purchase federal land and, in 1929, President Herbert Hoover signed a deed to the city for the land surrounding Arapaho Glacier. The purchase included four peaks along the Continental Divide and, combined with the city's earlier acquisitions from both private owners and the federal government, gave the city ownership of much of the land now contained in the Silver Lake Watershed. The city bought Green Lakes Nos. 1 through 5, located on Albion Creek in the Silver Lake Watershed in 1935. A private developer had constructed dams at Green Lakes 1 through 3 from 1902 to 1906 to raise the natural lake levels- The city would later make additional minor purchases of inholdings to complete its ownership of the Silver Lake Watershed area. The Silver Lake Watershed was closed to public access in the late 1920s after a cholera outbreak in order to protect water quality- In 1929, the city lowered the outlet pipe on the existing Silver Lake Dam to gain access to water in the natural lake area that had existed prior to creation of the reservoir. The entire original rockfill timber crib dam structure was replaced with an earthen embankment in 1940. The dam was enlarged in 1956 and again in 1966. During the Great Depression, public works projects continued to be built. Workers from the Work Projects Administration repaired the Goose Lake Dam and construction started on a new concrete dam at Island Lake to replace the dirt-fill wall. A steel-faced dam was built at Green Lake No. 3 and a 220-foot dam was built at Green Lake No. 2 to replace the existing dams. Following the dry years of the 1930s Dust Bowl, in 1937, the United States Bureau of Reclamation, in collaboration with farmers, ranchers, cities, and towns in northern Colorado formed the Northern Colorado Water Conservancy District (NCWCD)__ Facilities were built to bring Western Slope water into Lake Granby, though the Adams Tunnel over the Continental Divide and to the East Slope for use as a supplemental water supply. In 1947, the first of the Western Slope water flowed from the Colorado-Big Thompson (CBT) Project and into the South Platte drainage. In 1948, Public Service Company improved Barker Dam. The city entered into its first agreement with Public Service Company to use water from the Barker system by exchanging for water on North Boulder Creek in 1954 A new chlorination plant was built at Lakewood in 1949 because city water customers complained about the taste of city water at the irregular times when chemicals were applied at Lakewood. The city began adding chlorine to the water year-round so that customers would not notice a change of taste- Maxwell and Kohler Reservoirs were built and later covered. Boulder joined NCWCD in 1953. Boulder Reservoir was built in 1955 at the southern end of NCWCD. CBT water, from Carter Lake near Loveland flowed passed Lyons through the St. Vrain Canal and Boulder Feeder Canal, to Boulder Reservoir. The Bureau of Reclamation built a supply canal from Boulder Reservoir to Boulder Creek to deliver CBT water to downstream farmers and to carry CBT water for Boulder to exchange for additional water diversions at the municipal system intakes in the upper Boulder Creek basin. The Betasso surge chamber, having a 60,000-gallon capacity, was built in the 1950s on the Lakewood Pipeline portion of the Boulder City Pipeline near Orodell. Two chambers dissipated the energy that developed in the water as it flowed 3,000 feet down the mountain. Unfortunately, the surge chamber City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-3 caused air to become entrained in the water, which then caused sediment and contaminants to remain suspended in the water and increased its turbidity. Public sentiment against the negative effects of rapid growth dates back more than 50 years to the formation of PLAN-Boulder in 1959. Its primary purpose was to slow and direct growth in Boulder in order to preserve the college town's special qualities. The topic of metering came up again and found less opposition. A $4 million bond issue was proposed; $700,000 of that money would be used for the construction of meter pits near 7,500 Boulder households (prior to the election, the City Manager was accused of faking the need to conserve water by asking for summer restrictions for lawn watering). The bond issue passed. By 1962, 865 meters had been installed, and by 1965, the city was completely metered. In 1959, the City of Boulder and the Public Service Company signed a new agreement giving the city the right to use some of Public Service's water in Barker Reservoir, but the city could still only use Barker water indirectly through exchange for more water at Lakewood Reservoir- This changed with the construction of the Betasso treatment plant, which began in 1963. In 1964, the Betasso surge chamber was abandoned when the new Betasso treatment plant was put into service. A new agreement between the city and Public Service Company enabled the city to begin directly using Barker Reservoir water by delivery through new piping from the Boulder Canyon Hydro powerhouse to Betasso Water Treatment Plant. Barker Reservoir water traveled through a penstock to the hydro plant, then crossed Boulder Creek in a 20-inch pipe and terminated at Betasso's pressure-reducing chamber. An additional agreement between the city and Public Service Company was signed in 1968 that allowed for storage of 4,000-acre feet of city water. Eventually, the city gained the right to store 8000 acre feet of city water. Boulder purchased additional CBT Project water beginning in 1964 to increase the amount of water available at Barker Reservoir by exchange. Devil's Thumb Reservoir (formerly called Shanahan Reservoir) was completed during this period with a 5-million gallon capacity. The 2-million gallon Gunbarrel Reservoir was also constructed. In 1966, six northern Colorado communities (Boulder, Estes Park, Fort Collins, Loveland, Greeley, and Longmont) began discussions on the possibility of increasing their water supplies with the formation of a municipal subdistrict under the Northern Colorado Water Conservancy District. In 1969, the "Six Cities" group developed the Windy Gap Project, which would use the facilities of the CBT Project to carry water supplies eastward across the mountains and take advantage of the unused capacity of the CBT system. In 1979, the Colorado Supreme Court approved a conditional decree issued by the Water Court for 48,000 acre feet of Western Slope water to be divided by the six communities, of which Boulder received 8,000 acre feet. Construction of Windy Gap facilities began in 1981 and the project was dedicated during the summer of 1985. Fluoridation of Boulder water was on the November 1969 ballot. Fluoridation had been defeated three times before, but in 1970, after weeks of discussion and argument, Boulder approved fluoridation- In 1968 a bond issue passed providing $3 million to build Boulder's second treatment plant, the Boulder Reservoir WTF, east of Boulder Reservoir on 63rd Street. The plant was in operation by 1971 with a capacity to treat 8-mg of water per day during the summer months, April through October. Betasso doubled its capacity to a nominal 50 mgd in 1976 with a $2.4 million expansion. Water delivered to Boulder Reservoir from the CBT and Windy Gap Projects can be treated at the Boulder Reservoir Treatment Plant or exchanged to the city's municipal intakes on upper Boulder Creek for treatment at City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-4 Betasso. Betasso also treats most of the water derived from the city's native Boulder Creek water rights, but some Farmers Ditch water can be delivered to Boulder Reservoir plant. In the early 1980s, the city began to develop plans for hydroelectric plants that would generate electricity using the high pressures developed within the city's source water and treated water systems. Renewable energy generation by the city began when the Maxwell Hydro Plant began operating in 1985. In 1984, the city negotiated a power sales agreement with PSCo for three proposed hydroelectric projects on the city's raw water transmission pipelines-Betasso, Lakewood and Silver Lake Hydros. During 1986 and 1987, Kohler, Orodell, Sunshine and Betasso hydroelectric facilities were completed. The Silver Lake Hydro was completed in 1998, and the Lakewood Hydro went into operation in June 2004.. Xcel Energy purchases the hydroelectric power. 2.2 Water System History Update (Since 2000) A recent major event that impacts the city's entire water utility was the drought of 2002, the most severe single drought year in three hundred years. The drought resulted in mandatory water use restrictions in the city that caused water use to drop by 20 percent. Water use, discussed in further detail in Section 5 has not returned to historical levels. In 2008, the city fully implemented a water budget rate structure, where each user is assigned an amount of water they are expected to use based on water needs. Water rates per 1,000 gallons drastically increase once a customer's actual water usage exceeds the water budget. The water budget rate structure could potentially result in additional water conservation as users adjust their water use. An AWWA QualServeTA4 Report of Peer Review2 which reviewed the city's entire Utilities Division was published in 2008. This report presented strengths and opportunities for improvement for every aspect of the utility from Human Resources and leadership to customer service and water treatment. As with the other studies, the recommendations are covered in Volume 5. Since 2000 the Utilities Division attempted to coordinate their activities to a greater extent, considering outage scenarios in terms of how the entire water system would be affected: • One major source water system not available • One WTF out of service • One treated water transmission pipe out of service The following source water and water planning studies have been completed since 2000: • Water Conservation Futures Study • Drought Plan • Watershed Dams Evaluation • Lakewood Pipeline evaluations • Barker Facility assessments • Middle Boulder Creek Water Source Management Work Plan • Boulder Reservoir Watershed Management Resource and Information Guide • Source Water Impact Assessment • Instream Flow Studies • Water Conservation Plan • Climate Change Consequences for Boulder's Water Supply City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-5 Relevant conclusions from these studies are discussed in detail in Volume 4, SWMP. There is extensive source water system history information included in Volume 4, SWMP. Major changes in the source water system since 2000 include: • Barker Reservoir and the Boulder Canyon Hydro Project facilities were purchased from PSCo in 2001. Work to repair segments of the Barker Gravity Line has been ongoing since the purchase. • In 2004, the Lakewood Pipeline reconstruction was completed and the new pipeline went into service along with Lakewood Hydro. • Environmental and planning work has continued with NCWCD and other participants for the proposed Carter Lake Pipeline, for C-BT and Windy Gap water supplies from Carter Lake to Boulder Reservoir WTF. NCWCD is currently considering alignment alternatives for the project. • In 2009, a new 30-inch pipeline was installed to replace the Betasso Penstock. The existing Betasso Penstock was re-plumbed to become the Orodell Pipeline/Penstock, and the existing Orodell Pipeline/Penstock was re-plumbed to become the discharge line to allow excess raw water to flow back to Boulder Creek instead of entering Betasso WTF during capacity tests or run-of-river operations for Lakewood and Betasso Hydros. . • In 2009, the city worked with the Town of Nederland regarding upgrades to their wastewater treatment facility to improve the city's source water quality. Since 2000, several studies have been completed including. Relevant conclusions from the following studies are discussed in Volume 5, TWMP Update: • Boulder Reservoir WTF Predesign Report (2003), including an evaluation of mid-term and long- term improvements for the facility. • Boulder Reservoir WTF Source Water Quality Planning Study (Phase I Study) (2003) • Betasso WTF Facility Improvement Plan (2005) • Integrated Evaluation of the Boulder Reservoir WTF Source Water Protection and Treatment Improvements (Integrated Study) (2007). Improvements to the water treatment plants since the 2000 TWMP are described below. 2.2.2.1 Improvements at Betasso WTF Improvements to the existing solids handling facilities and the settling basins were completed in 2001. Near-term improvements were made to the Betasso WTF in 2007, including modifications to the residuals handling facilities to better accommodate contract dewatering, upgrades to the south lagoon, installation of a pump diffusion flash mixer and improvements to the carbon dioxide and polyaluminum chloride systems. Fast Maint by iGlobalCare preventive maintenance computer program was used extensively for the first time during 2008 at Betasso. An inspection of the Betasso WTF clearwell exterior paint in 2010 indicated that although the finish coat was oxidized and some of the coating was spalling, the underlying rust inhibitor coat was in good shape and no corrosion was evident. Therefore, the re-painting anticipated for 2010 can be delayed for an indefinite time period and City staff will continue to monitor the paint condition. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-6 2.2.2.2 Improvements at Boulder Reservoir WTF During 2001, the chlorine gas disinfection system at the Boulder Reservoir WTF was replaced with a mixed oxidant (MIOX) system. In 2009 this system was replaced with a sodium hypochlorite system. Near-term Improvements completed in 2005 increased the capacity of the plant from 8 to 16 MGD. Improvements included installation of two flocculation dissolved air flotation (DAF) trains within the existing flocculation/clarifier building; new residuals lagoons for dewatering the solids removed in the treatment process, installation of baffles within the existing treated water reservoir to improve chlorine contact time; the addition of two new high service pumps inside the existing filter building to pump water from the treatment plant into the distribution system. In order to reduce the turbidity and concentration of manganese in the plant influent, the city modified the Boulder Reservoir Intake Structure in 2005 by raising the elevation ten feet from the bottom of the reservoir. Boulder Reservoir WTF Mid-Term Improvements are ongong as of 2011 and include the addition of a third flocculation/DAF train for redundancy, addition of a fourth raw water pump for the reservoir source pump station (also for redundancy), addition of pretreatment carbon dioxide pH adjustment system, new flow monitoring, increased SCADA signal capacity, and improved operational flexibility with yard piping changes. These improvements will secure a firm capacity of 16 MGD for the WTF. The city systematically conducts distribution system rehabilitation. Although the city has been using a point system to prioritize pipes for replacement since 2002, between 2007 and 2009, the analysis became more rigorous. The city considers the following types of information for prioritizing pipes for replacement: age, material, break history, type of break, diameter, system pressure and soil type. This information is used in a statistical model based on the Weibull function. The city has adopted a goal of keeping annual breaks below 120, to stay within the range of "below average" breaks for municipalities in the region, based on AWWA benchmarking of utility performance. The city has been upgrading the Boulder Canyon and Sunshine Transmission system carrying water from Betasso into the city since 2000. In order to take the Sunshine Canyon pipeline out of service to make changes to the Sunshine Hydro, upgrades were required to the Boulder Canyon Pipeline. A bypass pressure reduction valve station was added outside the Orodell Hydro Station to allow more water past the hydraulic restriction at Orodell and the Fourmile Valve House was abandoned. A Report on Chautauqua, Kohler, and Maxwell Reservoirs was completed in 2002. As a result, Kohler Reservoir was relined in 2003 to effectively reduce leakage. In 2003, the water utility formed a water distribution system quality group to find ways to improve, or maintain, the water quality in the distribution system as the treated water was passed from the treatment plants to the customers. A program was developed in 2004 to remove the existing zone isolation valves from the distribution system. The purpose of the project was to prevent the accidental mixing of different pressure zones. This program has been ongoing. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-7 In 2005 a static mixer was installed as part of the Booton' Tank Water Quality Enhancements Project. Also installed were sampling lines in the tank that sample at various depths and remote monitoring of some water quality parameters. Control valves were installed to provide surge protection and remote control of opening and closing the tank inlet line. Work on the Unidirectional Flushing Program began in 2007 with MACTECH and then Merrick. MWH Soft took over development of Boulder's UDF design which was completed in 2009. The city has been evaluating the feasibility of using Sunshine Reservoir as a temporary storage facility for use during Sunshine Hydro Capacity Tests since 2007. An "all pipes" distribution system model, based on Infowater software, was calibrated by city staff in 2008. The model was calibrated so that all the modeled tank levels in the system matched to within 10 percent of monitored levels for a selected 24-hour period during the peak demand month. After calibration was completed, a long time period model run was made to locate the oldest water in the system to comply with the Stage 2 Disinfectants and Disinfection Byproducts Rule. Zone 1 Transmission System Improvements were needed to be able to supply more water to the system from the Boulder Reservoir WTF. The improvements include a new 24-inch diameter pipeline from the Boulder Reservoir WTF to the Iris Pump Station, which was completed in 2005. Upgrades to the Iris and Cherryvale Pump Stations were completed in 2010 to move 12.6 mgd from Zone 1 into Zone 2. A sister station was added at the Iris location and pumps, motors and the electrical system were replaced at Cherryvale. Water quality monitoring equipment was added at both pump stations. The TWMP (2000) identified two problems in pressure Zone 2. There is an area of very high pressures in east Zone 2 which was recommended to be isolated into a new reduced pressure zone. The TWMP also found pipes and PRVs in Zone 2 that have very high velocities during high flow conditions which should be corrected near the 101 Pearl Pressure Reduction Station. More recently, a study of the Zone 1 Distribution System identified pipes with high velocities in Zone 2 near the Iris Pump Station that could become problematic- In 2008, the velocities in the pipes in Zone 2 around the Iris Pump Station were checked and found to be lower than initially thought. Therefore, no pipe enhancement or replacement was required to assure performance of the Iris and Cherryvale pump station improvements. In 2008, Chautauqua Finished Water Reservoir Water Quality Improvements were completed, separating the inlet and outlet piping to enhance mixing potential, sampling lines and water quality monitoring meters were installed and the SCADA system was improved to allow remote monitoring of water quality. In 2008 a system-wide vulnerability assessment was completed. The vulnerability assessment prioritizes and recommends improvement measures for water system assets. Due to the confidential nature of the recommendations, they are not discussed in detail in the WUMP, although the budgets for the recommendations will be part of the CIP. An inspection of the Gunbarrel Reservoir in 2009 showed that the interior will require maintenance in the near future. Water quality sampling equipment was also installed at the Gunbarrel Reservoir. 1 a.k.a. North Terminal Water Storage Tank City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 2-8 3 Planning Approach and Assumptions The analysis includes estimates of demand and upgrades required for current conditions as well as the planning years 2015, 2025, and 2035. Water demands are estimated for the following user types: • Single family residential • Multi-family residential • Commercial/Industrial • Municipal Demands are developed for average daily, peak month, peak day, and peak hour conditions. Peak demands are developed using peaking factors. Demand information is summarized in Section 5. When recommendations are made for system improvements based on conditions in the planning years, the recommendations will be compared to buildout conditions, so that recommended improvements meet system needs beyond the planning year 2035_ This approach is consistent with the lifetime of assets in Boulder's water system, which may exceed 100 years. 3.1 Study Area The Boulder Valley Comprehensive Plan (BVCP) sets a course for the future growth and development of the city and the lands just outside the city's boundaries. The plan is jointly adopted by the city of Boulder and Boulder County. The BVCP defines three planning areas within the Boulder Valley: • Area I is that area within the City of Boulder which has adequate urban facilities and services and is expected to continue to accommodate urban development. • Area II is area now under county jurisdiction, but is planned for annexation and extension of city services. • Area III is the remaining area in the Boulder Valley, generally under county jurisdiction. Area III- Rural Preservation Area includes lands designated to remain rural in character. Area III-Planning Reserve is an area where the city and county intend to maintain the option of expanded urban development beyond the 25 year planning period The study area includes Areas I and II, which form the city Service Area. Population and employment numbers and spatial distribution were provided by the city Planning Department for 20103, the planning years 2015, 2025, and 2035, as well as buildout. Planning population City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 3-1 and employment numbers are based on recent conditions and trends. Buildout population and employment are based on the limits of current zoning and may not occur for decades. Buildout and year 2035 population are equal, but over 46,000 additional jobs are expected to be created between 2035 and buildout. Table 3-1. SW-,-t -,nfV of Planning Population and Employment 2010 2015 2025 2035 Buildout Single Family Residential 55,554 55,832 56,191 57,395 55,554 Population Multifamily Residential Population* 60,326 62,708 67,739 72,775 60,326 Total Population 115,880 118,540 123,930 130,170 130,170 Employment 99,750 103,890 111,180 119,180 165,230 *Includes population living in group quarters. 3.2 Land Use Land use information, consistent with the BVCP was provided by the city Planning Department. Land use for buildout conditions, as shown in Map 2, is very similar to current land use, with only a few areas expected to change. Population and employment are divided into the city's planning subcommunities (refer to Table 3-1) for current and 2035 according to Table 3-2. Between 2010 and 2035, employment is expected to increase by about 20 percent in each subcommunity but South Boulder, which would increase by 8 percent. Increases in population are more varied across the subcommunities with Crossroads, East Boulder, and Palo Park increasing by at least 30 percent and the remaining subcommunities increasing by 15 percent or less. Table 3-2. Summary of = ulation and Employme-1 , Subcommunity - Current and prrv.ic>r'".~^6 2010 2035 Buildout 2010 20351Buildout Area I + Area II Employment Employment Employment Population Population Central Boulder 22,280 26,710 27,670 31,260 32,400 Colorado University 10,280 12,480 14,520 8,730 9,480 Crossroads 15,870 19,300 29,410 7,180 10,850 East Boulder 21,460 25,440 39,450 3,920 6,170 Gunbarrel 15,260 18,130 29,280 10,480 12,030 North Boulder 4,590 5,480 7,070 11,910 12,670 Palo Park 360 430 2,580 3,330 4,330 South Boulder 4,900 5,300 5,300 16,730 17,050 Southeast Boulder 4,750 5,910 9,950 22,350 25,220 Total 99,750 119,180 165,230 115,880 130,170 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 3-2 i ni.T wa I F LM a a - - 3 1~ PTTwnAr Ay T C T p bhpenETn ' MaPee~ M r '"Tare GeVOn Briav AV i c"~•AAa ~ y n , a ~T Pw1Py n' ~•M ~ SY P•ASY R P°yl Sl ~wpde, - a~~, A~nPen•. Ar ~ ~ ATP,norN ic~.da I•ilY+.~~l.;~i a K unTTAq Ar - +J. Ae m 's BTeYOe HA - ~AVA'A~ - Yielee lY r~✓ 4 •`J'~0 ~ Y~AM•r RA F bai bl6M i yadaMaaO~ F-1 ANOL90 cre.eonu ei ny - ' .Y r 6 6emniln Legend N WLISA Boundary Land Use Community Agriculture Industrial Business Natural Lands Commercial Residential Current Land Use MWH 2 Miles Map 2 4 Laws, Policies, and Goals The actions of the Water Utility are guided in many ways by laws, city codes, ordinances, and policies. The major codes, policies and criteria impacting the utility's operations are summarized below. 4.1 Federal and State Laws The city must abide by all applicable federal, state, and local laws. The most prominent set of laws the water utility must consider in day to day operations are the Safe Drinking Water Act, the Colorado Department of Public Health and Environment (CDPHE) Drinking Water Program, and Colorado Water Law. The Safe Drinking Water Act (SDWA) was originally passed by Congress in 1974 to protect public health by regulating the nation's public drinking water supply109. The law was amended in 1986 and 1996 and requires many actions to protect drinking water and its sources, including rivers, lakes, reservoirs, springs, and ground water wells. The SDWA authorizes the United States Environmental Protection Agency (US EPA) to set national health-based standards for drinking water to protect against both naturally-occurring and man-made contaminants that may be found in drinking water. The agency in charge of water quality regulation and enforcement in Colorado is the Colorado Department of Public Health and Environment (see Section 4.1.2). Originally, the SDWA focused primarily on treatment as the means of providing safe drinking water at the tap. The 1996 amendments greatly enhanced the existing law by recognizing source water protection, operator training, funding for water system improvements and public information as important components of safe drinking water. This approach ensures the quality of drinking water by protecting it from source to tap. To ensure that drinking water is safe, the SDWA sets up multiple barriers against pollution. These barriers include source water protection, treatment, distribution system integrity and public information. Public water systems are responsible for ensuring that contaminants in tap water do not exceed the standards. Water systems treat the water and must test their water frequently for specified contaminants and report the results to states. If a water system is not meeting these standards, it is the water supplier's responsibility to notify its customers. The city of Boulder has actively participated in Colorado's Source Water Assessment and Protection (SWAP) program (a requirement of SDWA) and has developed an internal monitoring program to characterize source water quality and identify sources of pollution.2 2 Source water protection activities are described further in the SWMP City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-1 Additional discussion of water treatment and distribution regulations including their applicability and requirements for the city is included in Volume 5. The Safe Drinking Water Program of CDPHE is housed within the Water Quality Control Division which administers two major federal statutes as authorized by Colorado law: the Clean Water Act and the Safe Drinking Water Act. In addition to administration, including Colorado regulation development and enforcement, of the Safe Drinking Water Act and other Federal drinking water regulations, CDPHE's Safe Drinking Water Program provides the following services: • Capacity Development This service is a problem prevention service aimed at assisting public water systems in reducing and eliminating technical, managerial, and capacity weaknesses by providing tools and assistance. • Compliance Assurance This service is provided to assist public water systems understand the regulations, monitoring requirements, and public notification requirements. This portion of the program also assures compliance through an escalating enforcement program. • Excellence Program This service is aimed at continuously improving public water system performance and public health protection in Colorado. • Outreach and Assistance Program This service administers the federal Drinking Water Revolving Loan Fund which provides low-interest loans for eligible public water system projects. In addition to loans for capital projects, this service provides small grants for pre-loan planning and design projects. • Operator Certification This program component requires that all public water systems in Colorado, including Community, Transient Non-Community and Non-Transient Non-Community systems, be under the control of a certified Operator in Responsible Charge for both Treatment and Distribution (for systems that serve more than 100 people). The Colorado Water and Wastewater Facility Operators Certification Board (WWFOCB) maintains a program for the certification of operators of water treatment plants, municipal and industrial wastewater treatment plants, water distribution systems and wastewater collection systems in order to assure protection of public health and the environment. • Plans and Specification Reviews This program component requires every new public water system, or substantial addition or improvement to such a system, obtain approval of the plans and specifications by the Water Quality Control Division. The reviews are required to ensure that all regulatory issues are covered and that the design will result in the water quality improvements expected. Additionally, the review is conducted to ensure that the system operator will have the resources necessary to operate the systems. • Security and Emergency Response This program component provides assistance to public water systems as they strengthen their security program and prepare and implement emergency response plans. The program also provides continual updates of security information to systems that subscribe to the Security Listserve. • Source Water Protection This program service provides the public consumer information about their drinking water, as well as ways to get involved in protecting the quality of their drinking water. The program encourages community-based protection and preventive management City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-2 strategies to ensure that all public drinking water resources are kept safe from future contamination • Technical Assistance This program component sponsors activities that aid public water systems achieve compliance, optimize their operation, or provide education and training to their employees throughout the state and throughout the year. The program also provides telephone consultation, as well as on site assistance, training seminars, and workshops in technical, managerial and financial management topics. Discussion of the water treatment and distribution regulations including their applicability and requirements for the city is included in Volume 5. The city's right to use its water sources falls within the framework of Colorado Water Law. The doctrine of prior appropriation, often referred to as "first in time, first in right", is the basis of Colorado's water law system. The city's diversions into treatment and hydroelectric facilities, water it leases to irrigated agriculture, and flows left in streams for environmental purposes must all comply with Colorado water law.3 Colorado's water courts have jurisdiction over water right decrees and review cases related to water rights. The Colorado Division of Water Resources/State Engineer's Office has the authority to administer surface and tributary groundwater within Colorado. Boulder owns a diverse portfolio of water rights and water delivery contracts, which allow the city to use water both from the local Boulder Creek basin and from tributaries of the Colorado River to provide municipal water supply. These include direct flow rights, storage rights, exchange rights, and contract water delivery rights. Use under Boulder's many water rights is defined and limited by the terms of each water decree and water use contract. These terms can include limitations on types of use, diversion location, if and where water can be stored, season of diversion, if reuse after the first municipal use is allowed, maximum flow rate for the diversion, maximum storable amount, minimum instream flow levels and the all-important priority date as compared to other water rights. 4.2 State Constitution and City Code The city provides water, sewer and stormwater services by virtue of Article XX of the State Constitution (Home Rule of Cities and Towns) and the City Charter. The Utilities Division of the Public Works Department directs the day to day operations of the three utilities. The city operates its water, sewer, and stormwater systems as individual "enterprises" as defined in Article X, Section 20 of the State Constitution and Section 11-1 of the City Code.4 There are many ordinances contained in the City Code, B.R.C. 19814 that affect the water utility. The following sections are of particular importance. • Section 4-20 Fees, including the various fees charged by the water utility • Section 11-1-13 When Connections with Water Mains are Required • Section 11-1-14 Permit to Make Water Main Connections • Section 11-1-19 Water and Ditch Rights 3 Colorado water law and contracts related to water use are discussed in further detail in Chapter 3 of the SWMP 4 The water utility status as an enterprise is discussed further in Chapter 3 of the SWMP City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-3 • Section 11-1-20 Taps or Connections to Water Mains • Section 11-1-42 Agreement to Extend Water Mains • Section 11-1-43 Reimbursement of Costs for Water Main Extension Presently, the code requires immediate hook-up to the water utility upon annexation for commercial or public facilities if structures exist or are proposed and if they are adjacent to a water main- Private properties with existing or proposed structures must also connect if they abut a water main. 4.3 Boulder Valley Comprehensive Plan Since 1970, the city and Boulder County have jointly adopted a comprehensive plan that guides land use decisions in the Boulder Valley. The facilities and services section of the Boulder Valley Comprehensive Plans (BVCP) establishes policies linking growth to service standards and provisions found in the WUMP and other master plans. The following figure shows how the BVCP is intended to provide overarching guidance to city departments via their master plans, which feeds in to business planning and the Capital Improvement Program. '00 /fit MPrehe Busin-ass Plan Department Subcommunity 41- ~Ca:y a„~n~., ~trakegi! and * Master Plan AFe-a Plan$ •'rs ter. Operating Capital Improvement ❑evelopmsnt ' Budget Program Standards a and Zoning The following paragraphs of the BVCP are related to the water utility. • Protection of Water Quality - Water quality is a critical health, economic and aesthetic concern. The city and county will protect, maintain and improve water quality within the Boulder Creek watershed as a necessary component of existing ecosystems and as a critical resource for the human community. The city and county will seek to reduce point and nonpoint sources of pollutants, protect and restore natural water system, and conserve water resources. Special emphasis will be placed on regional efforts such as watershed planning and priority will be placed on pollution prevention over treatment. • Water Resource Planning and Acquisition - Water resource planning efforts will be regional in nature and incorporate the goals of water quality protection, and surface and ground water City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-4 conservation. The city will continue to obtain additional municipal water supplies to insure adequate drinking water, maintain instream flows and preserve agricultural uses. The city will seek to minimize or mitigate the environmental, agricultural and economic impacts to other jurisdictions in its acquisition of additional municipal water supply to further the goals of maintaining instream flows and preventing the permanent removal of land from agricultural production elsewhere in the state. • Drinking Water - The city and county will continually seek to improve the quality of drinking water and work with other water and land use interests as needed to assure the integrity and quality of its drinking water supplies. The city and county will employ a system-wide approach to protect drinking water quality from sources waters to the water treatment plant and throughout the water distribution system. • Minimum Flow Program - The city will pursue expansion of the existing in-stream flow program consistent with applicable law and manage stream flows to protect riparian and aquatic ecosystems within the Boulder Creek watershed. • Surface and Ground Water - Surface and groundwater resources will be managed to prevent their degradation and to protect and enhance aquatic, wetland and riparian ecosystems. Land use and development planning and public land management practices will consider the interdependency of surface and groundwater and potential impacts to these resources from pollutant sources, changes in hydrology, and dewatering activities. • Water Conservation - The city and county will promote the conservation of water resources through water quality protection, public education, monitoring and policies that promote appropriate water usage.. The city will endeavor to minimize water waste and reduce water use during peak demand periods. New development and redevelopment designed to conserve water will be encouraged. • Wastewater - The city will pursue sustainable wastewater treatment processes to achieve water quality improvements with greater energy efficiency and minimal chemical use_ Pollution prevention and proactive maintenance strategies will be incorporated in wastewater collection system management. The county will discourage the installation of private on-site wastewater systems where municipal collection systems are available or where a potential pollution or health hazard would be created. • Consistency of Utility Extensions with Comprehensive Plan - The installation and extension of all utilities will be consistent with the provisions of the comprehensive plan and with the responsibilities of the respective utility providers. • Efficient Extension of Utilities - Nothing within the comprehensive plan will prohibit the city from denying the provision of utility services to any property within the Boulder Valley for utility- related reasons. • Utility Provision to Implement Community Goals - The city will consider the importance of the other objectives of the comprehensive plan in the planning and operation of the water, wastewater, stormwater and flood management utilities. These other objectives include in-stream flow maintenance, enhancement of recreational opportunities, water quality management, preservation of natural ecosystems, open space and irrigated agricultural land, and implementation of desired timing and location of growth patterns. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-5 • Out of City Utility Service - In furtherance of policies 2.01, 2.02, 2.04, 3.08, 3.09 and 3.10, and not withstanding Policy 3.03, the city and county agree that it is appropriate for the city to: a) Decline support for utility provision in Area III and Area II when its provision would defeat Boulder Valley Comprehensive Plan goals. b) Extend limited utility service in Area III and Area II in circumstances that further comprehensive plan goals. c) Evaluate opportunities for cooperation with other utility service providers, in concert with the county, to further comprehensive plan goals. are 6ervice 6 andarc s According to the BVCP: • The urban service standards set the benchmark for providing a full range of urban services in the Boulder Valley. • These standards are intended to be minimum requirements or thresholds for facilities and services that must be delivered to existing or new urban development to be considered adequate. Five criteria are to be used in the determination of the adequacy of proposed or existing urban facilities. Each criteria has related urban standards for the water utility 1) Responsiveness to public objectives a) Provide a sr cient degree of reliability for mn, water, treated JJateJ; and an efficient tratrslrrissiorJ/distJiblrtiorJ ystenr capacity to weet the demands of the population 24 horcJS per day'. b) Provide f ill-trlne personnel 24 homs per day at the watev treatment plant to assni-e n'ater' gaaliy, lnonitot- equipment and make ell/eJgen(y means. r,) Have personnel on call 24 holsrs per day for water service emergencies 2) Sufficiency and dependability of financing a) Have revenue sources that are guaranteed so that revenues are available for natev related rllaterr.'als, tw,bltal improvement projects, eqn pment, facilities and personnel. b) Use Plant Investment Fees as possible revenue for mater rights acgrrasition, rawltreated xatet• storage, treatmelrtplarrt inzprovements/exfansions and ronstiiiction of mater mains. c) Be organised to request and receive state, federal, and Not-thetrJ Colorado iVater Conservancy District funds, w ben available, for egir pment, facilities and projects. d) Have the ability to obtain financing through the rise of revenue bonds. 3) Operational effectiveness Measures of operational effectiveness include current and long range project forecasting, coordination with other urban service programs, maximization of economies of scale in urban service provision, and the incorporation of operational processes and organizational methods that have proven effective in similar situations. a) Use annual budgetforpersonnel, eguplnent, projects, facilities and materials. b) Meet standard specifications as exemplified by the American TFater• TVorks Association. 5 Specific reliability criteria are discussed in Section 4.5. There are infrequent exceptions when not all of the demand for water will be met. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-6 c) Meet or surpass acceptable levels offederal and state hater quaky standards. d) City of Boulder Design and Construction Standards should be used for standards for crater main design for the Boulder Vally. 4) Proficiency of personnel a) All water treatment plants will be staffed by personnel who have obtained the appropriate TV'ater Operator Cel-tiji-cation. b) All water maintenance cress will be staffed by personnel who have obtained the appropriate ivater- Di.-striNition System Certification. 5) Location and adequacy of equipment and facilities a) Have capaciy to deliver sir rcient treated water to waxiinrrrrl day demand conditions. b) Have existing treatirierrt plant rapacity with planned expansion that will be capable of serving projected population of the Service Area. c) Plan and provide treatment capability to meet required water finality standards. d) On the divided highways, place hydrants on each side of highway. e) In single family residential areas, fire hydrant sparing shall be no greater than 500 feet No duelling unit shall be over 250 feet of fire department access distance f oni the nearest hydrant ineasiired along public or private roadways or fire lanes that are accessible and ironld be traveled by wotori:Zed fire fighting equipment f) In multiple family, industrial, business or corriinerrial areas, fire hydrant spacing shall riot be greater than 350 feet -No exterior portion of aig building shall be over 175 feet of fire departiuent access distance froiiz the nearest hydrant measured along public- or private roadways or fire lanes that are accessible and mould be traveled by niotorr:Zed fire fghtin eriu pment g) Provide essential egir pirient and vehicles for water maintenance activities and emergency use. 4.4 Utilities Division Mission and Guiding Principles The Utilities Division's mission is to provide quality water services, as desired by the community, in a manner which emphasizes efficient management of fiscal and natural resources, and protects human and environmental health. The Guiding Principles Utilities will use to fulfill its mission include: • Providing reliable utility services • Complying with all city, county, state and federal laws, taking direction from both regulatory standards and community goals • Planning work activities and expenditures in a manner which demands fiscal responsibility and accountability • Incorporating environmental stewardship, public health, and public safety in all aspects of our work • Understanding that our community is dynamic, not static, and as a result, so must be plans and programs • Treating people with respect, dignity and honesty • Setting high standards and consistently managing performance to achieve those standards City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-7 • Promoting staff as a team and resource • Maintaining a safe work environment • Realizing that the quality of our work is as important as the quantity of our work • Promoting personal responsibility, contributions and growth • Recognizing that we are a part of a larger organization and, as such, strive to understand other needs and use resources in a collaborative manner 4.5 Reliability Criteria Water provided by the city serves a variety of purposes ranging from those uses that require an assured supply such as drinking water and firefighting, to those uses that can tolerate occasional restrictions, such as lawn irrigation and car washing. It is recognized that no municipal water supply can ever be 100 percent reliable against all risk factors and that the economic and environmental opportunity costs of reducing the risks of occasional water shortages are significant. The BVCP (2008) includes different reliability criteria for the source water and treated water systems. The reliability standards for the city's municipal water supply that were adopted by City Council in 1989 based on the 1988 Raw Water Master Plan are: a) For those water uses deemed essential to the maintenance of basic public health, safety and welfare such as indoor domestic, commercial, industrial uses and firefighting uses, the city shall make every effort to ensure reliability of supply against droughts with occurrence intervals of up to 1,000 years. b) For the increment of water use needed to provide continued viability of outdoor lawns and gardens, the city shall make every effort to ensure reliability of supply against droughts with occurrence intervals of up to 100 years. c) For the increment of water needed to fully satisfy all municipal water needs, the city shall make every effort to ensure reliability of supply against droughts with occurrence intervals of up to 20 years- The city's Drought Plan (2003, 2004 and 2009 revisionsf includes four drought stages associated with increasing levels of water shortage severity. Drought stages will be declared based on review of a drought trigger formula specific to Boulder's water system and other relevant factors. Drought response measures appropriate to each drought stage are contained in the 2009 revision of the Drought Plan. Water budget reductions will be used as a primary tool at each drought stage. • Stage 1: Moderate, expected 20 to 50 year recurrence, reduce overall municipal water use by 8%, emphasis on wise water use. • Stage 2: Serious, expected 50 to 100 year recurrence, reduce overall municipal water use by 14%, surcharges and fines to eliminate wasteful use, more water use limitations such as decreased lawn irrigation. • Stage 3: Severe, expected 100 to 1,000 year recurrence, reduce overall municipal water use by 22%, measures to reduce excessive water use, outdoor use limitations with some loss of lawns, shrubs and minor trees. • Stage 4: Extreme, expected less than 1,000 year frequency, reduce overall municipal water use by 40% implement measures to eliminate most outdoor and non-essential water use, The city's efforts to maintain a diverse water supply, from both the east and west slopes, reduces the effects on water delivery from droughts or emergencies occurring in any one source watershed. The city City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-8 has modeled the source system for both current environmental conditions and a range of climate change scenarios. Without considering emergencies such as wildfires or a transmission system failure, the city is expected to meet the reliability criteria for current environmental conditions. Boulder would meet the most critical 100-year and 1000-year reliability criteria in all but one of eighteen climate scenarios modeled. The less significant 20-year criteria resulted in more frequent episodes of "nuisance level" minor water use reductions in one-third of the modeled climate change scenarios. The BVCP includes five reliability criteria from the 2000 TWMP (including two that have been moved to the Goals and Practices section, 4.6 and Appendix A). The reliability criterion of meeting all water demands with the exception of once in 20 years is the same for the source water and treated water system. The frequency of water use restrictions for essential uses and outdoor water use differ: a) The city will ensure the delivery of the water required to satisfy essential needs including the maintenance of basic public health, safety and welfare such as indoor domestic, commercial and industrial uses and fire fighting uses, except for droughts and system failures having a frequency of no more than once in 100 years. T;,-- avF,ccge ll~rr~ter r _;u,7~, 7 fiu l f_,s~ve aJ ci of !`)is b) The city will ensure delivery of the water required to provide for the continued viability of exterior landscaping, except for droughts and system failures having a frequency of no more than once in 50 years. The following method is used to establish a measure of this demand: ELD = AWC + 0.65 * (PMD - AWC) where: ELD = Exterior Landscaping Demand AWC = Average Winter Consumption PMD = Peak Month Demand As an alternative, 75 percent of the peak month demand may be established as a measure of this dem rid. c) The city will ensure delivery of the water required to fully satisfy all uses, except for droughts and system failures having a frequency of no more than once in 20 years. I ,e peak hour demand or itie peak ciay deaialid plus a fiie-fiov,,' ieselve uieirialiu is established as a measure of this demand. 4.6 Goals A variety of goals have been developed for different documents and internal use within the water utility. This section consolidates those goals, updates where necessary, and includes new goals developed through the WUMP process. In some cases, specific practices are suggested for meeting the identified goals. The following six overarching goals apply to the water utility as a whole. 1) Provide safe and high quality drinking water 2) Minimize interruptions to the delivery of water 3) Operate cost effectively 4) Consider other community goals in operating the water utility City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-9 5) Provide informative and responsive customer service 6) Foster communication and coordination among water utility staff in different locations There are five water quality goals described in the Water Quality Strategic Plan. The first three of these goals are intended to help integrate water quality and environmental considerations into capital projects and decisions regarding land use policies and activities. They include "provide safe and high quality drinking water", listed above. The next two goals, focus on wastewater and stormwater, but relate to the water utility in terms of source water protection: 7) Manage pollutants from wastewater and other point-sources 8) Manage pollutants from stormwater and other non-point sources The remaining goals represent the water utility's commitment to wise use and management of water and the environment, including operation of the Boulder Creek instream flow program and the water conservation program: 9) Protect, preserve, and restore natural water systems 10) Conserve water resources in a manner appropriate for Boulder's water supplies and system The various goals for the city's water rights and source water system are balanced against each other during implementation using the practices identified in Appendix A_ These recommended practices serve to achieve the best balanced outcomes for meeting the following goals: 11) Deliver the highest quality water sources available for immediate delivery after allowing for needed storage reserves 12) Maintain sufficient reservoir drought reserves to achieve drought reliability criteria 13) Maintain sufficient reservoir reserves to assure continuous water supply to Betasso WTF throughout the year and in emergencies 14) Maximize hydroelectric production 15) Address instream flow needs 16) Protect and enhance the yield of city's water rights portfolio 17) Maintain and protect source water system infrastructure and lands 18) Support local ditch company operations that complement the municipal system 19) Protect source water from point and non-point pollutants6 20) Encourage stewardship and regional cooperation, particularly with those entities affecting source waters and source water lands' 21) Improve source water quality when possible through operational or other means 6 The source water protection goals, described in the SWMP, have not been presented to City Council for formal adoption of an ordinance or policy statement, staff uses them as guidelines for operations and management- 7 The city does not own or control most of the lands that affect its water supplies, except in the Silver Lake Watershed and on North Boulder Creek, and cooperation with land-use management entities and interests is necessary City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-10 4, The following goals were documented in the Boulder Reservoir WTF Integrated Source Water and Treatment Study'. The city has established finished water quality goals that in many cases are more stringent than the water quality standards. These numeric goals are discussed along with water quality standards in Volume 5 of the WUMP_ Appendix A includes recommended practices to meet the following goals. 22) Comply with all drinking water regulations and meet secondary standards. 23) Use best practices to maintain high quality treated water. 24) Seek alternative methods to increase delivered water quality. 25) Deliver similar and consistent finished water quality from both plants. 26) Ensure daily reliable plant operations at design flows 27) Integrate public health risk factors into source water and treatment management decisions. 28) Improve knowledge of emerging contaminant occurrence The following distribution system goals have been established as part of this and previous planning efforts. Appendix A includes recommended practices to meet the following goals. 29) Remain in the "below average" category for water main breaks for municipalities in the region 30) Design and operate distribution system with adequate storage to meet fluctuating customer demands and provide for emergency service 31) Maintain safe and consistent water quality throughout the distribution system. 4.7 City of Boulder Design and Construction Standards The city publishes design and construction standards including a chapter about water8. BVCP requires that water mains be constructed according to these standards. The design and construction standards are all related to the distribution system and are described in detail in Volume 5. 4.8 Additional Master Plan Design Criteria Criteria for the design of specific facilities serve as an important guide in evaluating the facilities and in making recommendations for current and future improvements. This section recommends criteria in addition to those contained in the BVCP and Design and Construction Standards for use by the city in this and future planning efforts. These criteria build upon those published in the TWMP (2000) including the American Water Works Association (AWWA), the National Fire Protection Association (NFPA), Uniform Fire Code (UFC), Uniform Plumbing Code (UPC), and the Insurance Services Office (ISO). Adequate design capacities and appropriate operational guidelines for the source water system cannot be derived solely by looking at average water availability from each water source. This is due to significant variation in year to year and seasonal availability of water from each of the city's water sources. In addition, conditions in one location in the watershed can have impacts in another part of the watershed in unexpected ways due to water rights interactions and interrelated aquifer and river hydrology. Therefore, extreme hydrologic events and variations in water availability between east slope and west slope sources need to be considered when setting design criteria for facilities. This can best be done by reviewing design criteria in conjunction with output from the city's Boulder Creek Watershed Model, which models long-term operation of the source water system through a range of expected hydrologic conditions. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-11 System modeling shows that the currently available amount of reservoir storage space will allow the city's existing raw water supplies to be capable of meeting buildout water demands up to the level of the city's adopted drought reliability criteria. In order to achieve this level of reliability, the city must follow operational practices that maximize use of direct flow water rights and emphasize adequate use of treatment capacity at Boulder Reservoir WTF in order to retain sufficient reserve storage water in the city's upper Boulder Creek reservoirs. In most years, there is enough streamflow at the city's Boulder Creek diversion points for a few weeks to a few months during spring runoff of mountain snowmelt for all of the city's then-occurring water demands to be met through direct flow diversions without pulling water from storage reservoirs. This is known as the "direct flow season". Streamflows usually are also high enough at this time to fill reservoirs. However, natural streamflows drop significantly by late summer and are only a few cubic feet per second during the winter. During these seasons, the city must draw water from its reservoirs to supplement direct diversions in order to meet municipal water demands. In years in which the city's reservoirs do not fill in the spring, municipal water needs must be met by drawing down drought storage reserves carried over in reservoirs from wetter years. Therefore, the city must maintain sufficient reservoir storage capacity to even out water availability between seasons and between wet and dry years. On-going use of Boulder Reservoir WTF during all months but the direct flow season helps to protect the city against drought shortages. Improving the ability to deliver water to the Boulder Reservoir WTF during the winter, such as with the construction of the Carter Lake Pipeline, will support efforts to be prepared for drought. An additional portion of upper Boulder Creek reservoir storage in each basin should be dedicated to holding an emergency reserve to assure continued deliveries to Betasso WTF in the event of an emergency. It is important that Betasso WTF be able to operate with very few interruptions in order to prevent the possibility of pressure loss in the upper zones of the distribution system in the city. The disruptions in Betasso operations that do occur should be limited to no more than a few days. Each of the city's water sources should have facilities that are designed with sufficient redundancy to assure that there will always be at least one source of raw water available to the treatment plants in the event of an emergency. Each water source should be able to independently provide at least the essential buildout water demands of the city in order to provide the greatest protection against unplanned outages that might jeopardize public health or safety. Raw water pipelines to Betasso WTF should be maintained with sufficient capacity to meet the maximum treatment capacity of the plant when both pipelines are operating. The city sets water budgets for individual customers based on an evaluation of the amount needed for their household and irrigation water needs. Outdoor use allocations in the summer months are generally based on calculations of evapotranspiration for bluegrass lawns. However, budgets for May and June are purposefully set higher to avoid discouraging water use during the direct flow season. This practice maximizes beneficial use of water for landscaping irrigation during periods when it will not affect the city's drought resiliency. It takes advantage of the alluvial aquifer feeding Boulder Creek ability to act as another reservoir by encouraging irrigation practices that will recharge the aquifer. Water from the aquifer then returns to Boulder Creek on a delayed basis at times when streamflows are naturally dropping in summer and fall. In addition to supporting streamflow, the return flows soften the water rights call on the river and preserve the city's ability to continue diverting under its water rights in the upper Boulder Creek basin. Therefore, the city's water pipeline capacities should be designed and maintained so that all of the city's demands can be met through direct flow deliveries, mostly through Betasso, during the period of about mid-May to late June in most years. In addition, water conservation programs and water budget amounts should be designed in a manner that considers the broader watershed effects and benefits of city water use_ City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-12 The city has used the Boulder Creek Watershed Model to design the Drought Response Plan. The drought reliability criteria have been used in the modeling as assumptions on the percentage of water use reductions that will be in place during drought years. In order to achieve the model results of having the city meet the drought reliability criteria over time, the city must design and implement its drought response activities to achieve the assumed percentage of use reductions. A key component of this reduction effort will be reductions in customer water budgets. It should be noted that the water budget reductions currently in the drought plan are based on the current ratio of 60% indoor use and 40% outdoor use. The city deliveries as much of its municipal water supplies as possible without jeopardizing drought resiliency through the Betasso WTF in order to maximize hydropower production and to minimize treatment and pumping costs. It can cost up to five times as much to deliver the same amount of water from Boulder Reservoir WTF as from Betasso. However, all water supplies available under the city's water rights for the Boulder Creek basin in any given year are not delivered to Betasso in that year because some is held in reservoirs for balancing seasonal availability of supplies, as a drought reserve, or for an emergency with one of the city's water sources. This is a risk calculation that can be guided by water system modeling and staff experience with the goal of assuring that there will always be a source of water to feed Betasso, even under the most severe conditions. The city's Colorado-Big Thompson Project (CBT) water supplies are considered a supplemental water supply to native basin water. In years when eastern slope watersheds are yielding less than average, the NCWCD board sets a higher quota for CBT water. Therefore, during drier periods, Boulder will likely need to treat more water at the Boulder Reservoir WTF. In severely dry years, more than half of the city's annual water supply may be treated and delivered from Boulder Reservoir WTF. This may not be the case, if river flow conditions on Boulder Creek allow the city to exchange its CBT water for more water at the upper Boulder Creek diversions. This exchange potential varies from year to year as well- Boulder's exchange rights allow it to divert additional supplies at its upstream points of diversion, which provides for diversion of higher quality water, gravity delivery, and more water stored in the city's 18,000 acre-feet of mountain reservoirs. The city's exchange rights allow the cost-effective movement of water from the city's lower water system into its upper water system without the need to construct an expensive pipeline or pumping system. The increase in water available to the city's upper water system also increases hydropower generation. Water treatment costs are reduced due to use of the exchange because it is less expensive to treat the higher quality water available to Betasso WTF than water at Boulder Reservoir WTF. Also, water from Betasso WTF can be delivered into the city by gravity instead of by pumping, as is required for Boulder Reservoir WTF water. This both saves money and reduces greenhouse gas emissions associated with the electricity for the pumps. Water system facility capacities and water operations are based on the assumption of Boulder's continued use of its Boulder Creek exchange rights. Boulder can add to water available under direct flow water rights by exchanging CBT or Windy Gap water for direct delivery to Betasso WTF at rates of more than 20 cfs (13 MGD). Concurrently, at buildout, the city might deliver water via the Boulder Reservoir WTP at rates of 8 to 12 MGD in order to meet Boulder's summer demands. Shifting the delivery of the water used to drive Boulder's direct use exchanges to the Boulder Reservoir WTP would therefore require an increase in the treatment capacity of that plant by up as much as a total capacity of 25 MGD. Other facilities, such pumping plants and transmission pipelines from the Boulder Reservoir WTP into the city, would also need to be increased in size. Therefore, without the river exchange, significant capital investment would be required on one side of the water system along with abandonment of full use of existing facilities capacity on the other side of the water system. For these reasons, use of the Boulder Creek exchange should be maximized. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-13 Operational modeling of water availability at each of the city's treatment plants shows that, at buildout, on average over many years, Betasso WTF will treat 56% of the city's water and Boulder Reservoir WTF will treat 44%. In wetter years, the amount treated at Betasso could increase to 67%. In drier years, the ratio will be closer to 50/50. There are monthly variations within the annual variations. In some months, Betasso may be supplying all of the city's water with a maximum of about 1060 acre-feet in a month or 45 MGD average. However, Betasso may shut down for a few days in winter months during drought years with Boulder Reservoir WTF supplying most of the 13 to 15 MGD needed in those months. By the time of the city's full buildout, Boulder Reservoir WTF will need to run at a fairly constant base load between 10 to 16 MGD for about ten months of each year in order to balance use of available water supplies in a manner that protects drought resiliency. It may need to run at a continuous rate of up to 16 MGD during some of the summer months in order to adequately balance use of Boulder's available water supplies and maintain appropriate drought reserves in the upper Boulder Creek reservoirs. At buildout, Betasso WTF will operate almost every day of the year, with low flows through the facility in winter and high flows in summer. The city has developed much of the environmentally and economically feasible hydroelectric generation potential in its raw and treated water delivery system. This potential exists because of large changes in elevation between the city's diversion points and delivery points for its municipal water pipelines. The city's eight existing hydroelectric generators produce electricity with minimal environmental impact since the water supply infrastructure is already in place. There are additional sites within the water system that may have hydro development potential if the electricity can be sold at a price that returns the investment in equipment. The potential hydro development sites on current water system facilities that have been identified based on the available pressure or the amount of flow available are: • 101 Pearl • Discharge line from Betasso (Tram Hill Hydro) • Barker Dam outlet to Boulder Creek (Hannah Barker Hydro) Of these, only the Hannah Barker Hydro proposal appears to be financially feasible, but only after a new outlet works is constructed at Barker Dam as planned to meet water system operational needs. The other two sites appear to have insufficient flows either in volume or over time to justify the expenditure for hydro equipment, but this might change at some point in the future. Other hydro sites might be identified or become feasible when new facilities are built or older ones are refurbished. For example, the proposed Carter Lake Pipeline should have hydro potential at the discharge at Boulder Reservoir WTF_ Consideration of the possible addition of hydro facilities should be a design consideration for any water system project involving an untapped source of water pressure. Water system improvements proposed in this study are designed to supply peak requirements as determined from water use studies. In designing transmission system and distribution system components, consideration is given to peak day demands and fire flow requirements as well as peak hour demands. It is assumed that fire flow will be provided coincidentally with demands at the peak day rate. Within the existing treated water distribution system, pressures at some locations can reach over 160 psi. System additions, however, should be designed in such a manner that pressures in new areas would be City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-14 about 80 psi and limited to approximately 100 psi. The Uniform Plumbing Code requires individual house pressure regulators for pressure above 80 psi. Minimum NFPA required residual pressure at fire hydrants is 30 psi under normal service conditions and 20 psi under fire flow conditions. The BVCP design criteria listed earlier in this section call for a minimum pressure of 40 psi in residential areas during periods of peak hour flow. Distribution system additions should also be designed to limit the daily pressure variation at any point in the system, which occurs as demand varies from minimum to maximum, to approximately 20 psi. Storage facilities are required to: a) provide equalization of peak demands, b) meet fire flow demands, and c) meet emergencies. When possible, storage should be provided in elevated tanks which 'float' on the distribution system pressure. Such storage is more reliable than clear well or offline storage, which requires pumping. Storage tanks should be designed to meet the following standards as applicable: NFPA 22, Water Tanks for Private Protection Standards; and AMA standards for steel tanks, standpipes, reservoirs, and elevated tanks. 4.8.5.1 Equalization A storage volume equivalent to 25 percent of the peak day demand should be provided to equalize daily demand fluctuations. The storage volume should be determined separately for each pressure zone in the system. 4.8.5.2 Reserve for Emergency Purposes Provision of emergency reserve is governed primarily by considerations of mechanical and power outages. In this regard, it must be assumed that mechanical failures could result in the random outage of any single supply component for a period of several hours to several days. On the other hand, the duration of power outages varies with location and relationship to the power distribution network. The Betasso WTF for example experiences power outages lasting from 10 minutes to over 24 hours from winter storm events. The Boulder Reservoir WTF experienced a significant number of power outages in the 2002 to 2005 timeframe due incoming power line issues. Since replacement of the line and power pole in 2005, power outages have nearly ceased and the supply is considered very reliable. However, it is assumed that outages could occur at any one location coincident with a fire flow requirement. Storage reservoirs should be operated such that they drain during the day when system flow is high and fill during the night when system flow is low. This tends to level off treatment plant flow variations resulting in more stable operation and helps maintain an adequate chlorine residual in the reservoirs. However, no reservoir should be allowed to drop below the level that represents a stored volume equal to the required fire flow plus emergency reserve for the zone served by that reservoir. Fire flow rates and durations for various types of development are given in Table 4-1 together with the storage volume required to meet these demands. In applying these standards, the worst case of fire flow is assumed for each zone. Fire flow is calculated independent of equalization storage because these are assumed to be concurrent. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-15 Fire Flow Requirements Breakdown Fire Flow Duration Fire Storage Required Land Use (gpm) (hours) (gallons) Single Family Residential 1,500 2 180,000 Multifamily Residential 3,500 3 630,000 Commercial 3,500 3 630,000 Schools 2,500 2 300,000 Hospitals 6,000 4 1,440,000 Industrial 3,500 3 630,000 Fire storage should be determined and provided separately for each pressure zone within the distribution system. Recommended storage requirements for the City of Boulder from the TWMP (2000) are: Fire Fighting Storage Zone (million gallons) 1 0.63 2 1.44 3 1.44 In addition to the BVCP criteria, fire hydrants should be located so that each will serve between 80,000 and 150,000 square feet of developed area9. An ISO fire insurance classification completed in 1995 found that the city's water supply system for fire suppression was very good, receiving 38 out of 40 possible points. This evaluation reviewed water main capacity and hydrant distribution' 0 These facilities should utilize automatic pressure reducing valves as opposed to manually actuated valves whenever possible, to reduce the potential for human error. This will provide for consistent system operation under all conditions. If additional control is desired, a manually actuated valve can be placed in series with an automatic pressure-reducing valve. The piping system which is used to deliver water from the treatment plant to customers normally consists of transmission mains and distribution mains. Transmission mains deliver water from treatment plants and storage to major subdivisions of the service area, and are generally 12-inch diameter and larger. Distribution mains convey water from the transmission system to individual users and are generally 10- inch diameter and smaller. In planning future improvements, it is assumed that existing mains will be fully utilized. Transmission mains are sized to deliver the greater of either peak hour demand or peak day demand plus fire flow. Maximum velocity should not exceed 10 feet per second. Sizing of transmission mains is based on the results of hydraulic analyses of the distribution system. It is recommended that transmission main piping be manufactured of lined steel or lined ductile iron, meeting the requirements of AMA C200 or C100, respectively. Distribution mains are recommended to be constructed of PVC or polyethylene wrapped lined ductile iron, meeting the requirements of AMA C900 or C100, respectively. On transmission pipelines valves should be spaced at approximately 1,200 feet". City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-16 Pumping facilities should be designed to meet peak day demand with the largest pump out of service. In addition, design of pumping plants should consider extreme events, such as an outage of one major part of the system. City staff should consider if pumping facilities should be designed with the capacity to meet demands when one major part of the water system is out of service. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 4-17 5 Water Use This section discusses historical water use, baseline water use (for the period 1994 to 1996), current water use, peaking factors, and projected water use. 5.1 Historical Water Use The following is brief a summary of the historical water use discussion in the SWMP, which can be found in Volume 4, Section 5 of this WUMP. Figure 5-1 shows the long term trend in the city's total treated water use. Water use followed an increasing trend from the early 1970s until 2000. The drought of the 2002 resulted in lower total water use, and levels have remained similar since Figure 5-2 depicts long-term historical outdoor water use, compared to outdoor water use requirements (based on evapotranspiration, or ET). Although outdoor water use can vary greatly from year to year based on weather conditions, indoor water use in the last few years has been similar to usage in the 1980s- This suggests that permanent structural changes have been made, such as the installation of water efficient toilets and appliances. Outdoor water use has fluctuated since the drought of 2002 and it is not clear if outdoor water conservation noted during the drought year will be permanent. 30,000 25,000 20,000 a~ d 15,000 v a 10,000 5,000 Li _J I- _J L_ O M h O M ~A ^ O M try l~ O - M h N n O W O O O O O O O O O O O O O O O O O O O O O O O M O O O O O O O O O w a n n w a n n w n n w N N N N N year City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-1 100 - 160% 90 140% coo 80 v 120% w Q. O 70 m 60 100% c L ar O E O 50 60% m O Cr .3 40 60% W CL c M 30 O U 40% ~ L L 20 i 10 20% m Z 0 0% p w r rn M Ln r- w a) Ln n m m Lo r w n n r n n m co m m m m rn m rn M o 0 C. 0 0 M rn m rn rn m rn rn rn m rn m m rn o 0 0 0 0 r - 9! r r 1- - r r 91 r - r N N N N N M Per Capita Outdoor Use, gpcpd --Net ET, % of average 5.2 Baseline Water Use (1994 to 1996) The Water Conservation Futures Study involved a detailed study of water usage in the city and established baseline water usage data by customer type that are still relevant to the WUMP. The baseline water usage data, summarized in Table 5-1, were for the years 1994 through 1996, with an adjustment for the low evapotranspiration requirements of that period. These data are a baseline, because water conservation goals adopted by the City Council in 2000 are relative to these figures. Table 5-' rvation Futures Stu:- Sector Unit Usage Water Use Sector Total Usage (AFY) Sector Units (gallons per unit per day) Single Family Residential 7,681 46,072persons 148 (detached) Multi-family Residential 6,217 61,584* persons 90 (attached) Commercial/Industrial 5,924 85,401 employment 62 Municipal 724 Total use 646,000 Unaccounted for Water 1,899 Total use 1,695,000 Total Produced 22,446 107,655 Total Population 186 *Includes group quarters population, estimated as 8,000 persons. The data published in the Water Conservation Futures Study was slightly modified in coordination with city staff as the numbers were not published in the format of Table 5-1 and some of the numbers could not be directly reproduced14. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-2 5.3 Current Water Use Based on the consensus of staff, current water usage is based the four year period 2006 through 200915. Figure 5-3 and Table 5-2 show how current usage has varied and how it is divided into sectors. Water production varied from 20,372 acre-feet in 2006 to 17,280 acre-feet in 2009. Water production did not trend exactly with the net irrigation requirement, which varied from 88 percent of average in 2009 to 117 percent of average in 2007. The average production of 18,800 acre-feet shows that water usage has been reduced compared to the baseline period (1994 to 1996) when there was over 22,000 acre-feet of total water use. Over the four year period, net irrigation requirements were 103 percent of the long-term average16. The evapotranspiration (ET)-adjusted average production for the period is 18,587 acre-feet. through 2009 and 25,000 L } 20,000 Unaccounted for CL W 15,000 - ■ Municipal Commercial / Industrial u a 10,000 °J ■ Multifamily Residential 61 5,000 ■ Single Family Residential 0 3 0 2006 2007 2008 2009 06-09 Avg 20,372 18,620 18,928 17,280 18,800 L Table 5- : sstoric Water Usage - 2006 through 200 .,riod Average (Acre-Fie ET-adjusted Sector 2006 2007 2008 2009 Average Average Single Family Residential 7,207 6,835 6,849 6,115 6,751 6,662 Multifamily Residential 4,572 4,342 4,398 4,086 4,349 4,313 Commercial/Industrial 6,115 5,884 5,631 5,094 5,681 5,624 Municipal 821 860 778 592 763 745 Total Consumption 18,714 17,920 17,656 15,886 17,544 17,344 Unaccounted for 1,658 700 1,272 1,394 1,256 1,243 Total Production 20,372 18,620 18,928 17,280 18,800 18,587 Net evapotranspiration requirements 109% 117% 97% 88% 103% NA City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-3 Table 5-3. Current Water Based n- `justee - le of 2006 through 2009 Sector Units Total Usage (based on 2008 population and Sector Unit Usage (gallons Water Use Sector (AFY) employment) per unit per day) Single Family Residential 6,662 49,500 persons 117 Multifamily Residential 4,313 63,600' persons 62 Commercial/Industrial 5,624 100,500 employment 50 Municipal Gallons per day 665,000 745 (gallons per capita per day) (5.9) Unaccounted for Water Gallons per day 1,110,000 1,243 (gallons per capita per day) (9.8) Total Produced 18,587 113,100 Total Population 147 *Includes group quarters, estimated as 9,733 persons. 5.4 Projected Water Use Projected water usage is based on historical water usage, planned population and employment and conservation goals adopted by City Council. The conservation goals, which are applied to the baseline water usage (summarized in Table 5-4) are as follows: • A 22 percent reduction in per-meter use for the single-family residential sector • A 26 percent reduction in per meter use for multifamily residential sector • A 14 percent reduction in per meter use for the commercial/industrial sector • A one percent reduction in overall municipal use • A 15 percent reduction in unaccounted-for water Table 5-4 summarizes baseline, current, and full conservation unit water usage. In nearly every case, the conservation goals have already been exceeded. Total municipal water use has slightly increased in total, but has decreased per capita. Although it appears that the single family sector goals have not been met, this is likely due to differences in how the population is counted compared with how water use is tracked. ahls =d, SC l~S``s di"1( Jl: 31i lv Y 1>C`_ _6 , ~,.~Ii Gcals (gcaHo , , :y unit per day) Conservation Sector Baseline Goal Current Units Single family Residential 148 115 117 Gallons per person per day Multifamily Residential 90 67 62 Gallons per person per day Commercial/Industrial 62 53 50 Gallons per employee per day Municipal 646,000 640,000 665,000 Gallons per day Unaccounted for 1,695,000 1,440,000 1,110,000 Gallons per day 05.7) (13.4) (9.8) (gallons pei catA'a'oer"day) Total production 186 149 147 Gallons per capita per day City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-4 For planning purposes, the current unit water usage rates are applied to projected population. The planned densification of Boulder's population, where new developments cover a smaller area per person, and its expected effect of reducing per capita water usage, is at least partially reflected in the WUMP due to the shift of the population to more multifamily housing. Although it is possible that residents will continue to reduce unit water consumption in each sector through conservation, the likely level of future conservation has not been studied in detail and new goals have not been established. If warmer and drier conditions occur in the future due to climate change, the additional need for outdoor water use may counteract some of the conservation efforts. One of the recommendations of this plan is that a study of likely future water usage be conducted in order to better plan for the water utility. Table 5-5 and Figure 5-4 summarize total service area water usage used for planning in the WUMP, based on population information summarized in Table 3-1. Customer Type Units 2010 2015 2025 2035 Buildout Single Family Residential AFY 6,830 6,830 6,820 6,990 6,990 Multi-family Residential AFY 4,420 4,620 5,000 5,330 5,330 Commercial/Industrial AFY 5,590 5,810 6,230 6,680 9,250 Municipal AFY 760 780 820 860 860 Unaccounted for Water' AFY 1,230 1,260 1,320 1,390 1,570 Total Produced AFY 18,830 19,300 20,190 21,250 24,000 Total Produced2 MGD 16.8 17.2 18.0 19.0 21.4 1 Unaccounted for water estimated as 7 percent of total demand, not on a per capita basis. 2 In accordance with Distribution System Goal No. 30 and its associated recommended practices (see Appendix A), an additional 10% "reserve capacity" is added to these numbers for distribution system planning and analysis to allow a degree of planning flexibility and mitigate water delivery problems that might be caused by operator error. Figue 30,000 R 25,000 L d ~ 20,000 Unaccounted for v ■ Municipal L 15,000 a Commercial / Industrial H 10,000 ■ Multifamily Residential L 5,000 ■ Single Family Residential 3 0 2010 2015 2025 2035 Buildout City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-5 5.5 Peaking Factors Typically, treatment facilities are designed with adequate capacity to meet annual peak day demands and distribution system facilities to meet peak hour demands. City of Boulder reliability criteria were used as the basis for selecting appropriate ratios of peak day and peak hour to average day demand. The reliability criteria stipulate that the city's treated water system should have the ability to satisfy demands except for droughts and system failures having a frequency of not more than once in 20 years. The reliability criteria mean that the system should be designed to meet the 95th percentile of the historical annual peak demands. Long-term trends in peaking factors are presented as available in the following sections for consideration. However, as the composition and water usage of the city has changed over the decades, it may not be appropriate to use statistics based on a period longer than 10 years- Therefore, statistics presented are based on the 10-year period 2000 through 2009. Peak factors selected for use in the WUMP are based on discussion with city staff to ensure that the factors are acceptably conservative. All peaking factors are calculated in comparison to the ET-adjusted "current water use" consumption of 18,587 acre-feet per year, or 16.59 MGD, based on the period 2006 through 2009. The peak month of demand occurs in the summer due to the height of irrigation water use. The peak month demand was not discussed in the 2000 TWMP, but can be useful for understanding how water usage changes throughout the year. Analysis of recent water usage data 17, as shown in The 95th percentile peak month factor of 2.0 will be used for any analysis requiring a monthly peaking factor as this corresponds to the city's reliability criteria. Figure 5-5, shows that although there is variation in peak month to average month demand from year to year, there is no apparent trend with time. However, peak month factors do trend somewhat with the net irrigation requirement. Hot, dry summers would tend to increase summer water usage compared to the long-term average, resulting in higher monthly peaking factors. Between 2000 and 2009 the ratio of peak month to average month varied from 1.4 to 2.1 with an average of 1.8 and 95th percentile of 2.0. The 95th percentile peak month factor of 2.0 will be used for any analysis requiring a monthly peaking factor as this corresponds to the city's reliability criteria. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-6 Figure 5-5. ''---nt Historical Ratio of Peak Month to Average Day Demand 3.0 140% 2.5 120% ~ Y 100% E 2.0 v L 3 O~q j 80% a L 1.5 60% o a 1.0 Ln 3- L 40% C) a t 0.5 Peak Month Factor 20% Z Net Irrigation Requirement 0.0 0% 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 3.0 140% 2.5 120% f0 = 100% C) 2.0 a, p L j - 80% a Q = 1.5 r_ Q 60% 4- 0 1.0 L L - 40% Z d m CL 0.5 Peak Month Factor z 20% Net Irrigation Requirement 0.0 0% 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Figure 5-6 shows how peak day water usage has changed over the years since 1971. The ratio of peak day to average day water usage declined from about 2.5 in the early 1970s, to a low of around 2.0 around 2000. In more recent years, the peak day ratio has increased to around 2.28. The 1990 master plan used a peak day to average day demand factor of 2.81. The 2000 TWMP noted a five year average factor from 1994 to 1998 of 2.4, but selected a more conservative peak day factor of 2.6. Although this information is 8 The long-term data are not compared to the 2006-2009 "current water use". City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-7 reported in the text of the 2000 TWMP, it does not match the associated figures nor the historic information presented in Figure 5-6 below. The reason for this discrepancy is unknown. 60 3.00 50 2.50 o ° ,a 40 2.00 ~ 4 a d - w is T 30 1.50 m o . x a m a 20 1.00 10 0.50 0 0.00 'J h N 4f 17 10 n O n h n o~ M h N M I ~ NN 1 n O O CO N W O rn O m rn O O O O O 0) C35 a) CY, Z~ Z 2 2 2 Z N N N N N Peak Day Use, MGD t peak Ratio - Linear (Peak Ratio) More recently, from 2000 through 2009, the peak day factor fluctuated between 1.8 and 2.7 (see Figure 5-7). The average and 95th percentile daily peaking factors for this period were 2.2 and 2.6, respectively19. The peak day factor has not exceeded 2.3 since the year 2001. However, to remain conservative and match the reliability criteria, a daily peaking factor of 2.6 is appropriate for planning studies- 3.0 140% 2.5 120% T C 0 100% E 2.0 _ oa 80% y 1.5 > ~ Q 60% +o , p 1.0 d 40% 0.5 --11- Peak Day Factor 20% z - Net Irrigation Requirement 0.0 0% 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-8 The 2000 TWMP found that historic data from 1971 through 1989 had a 95th percentile peak hour to average day ratio of 4.45. More recent data were not available at that time for a peaking analysis. The TWMP concluded that the peak hour factor is highly variable and may not be following a downward trend. Therefore, a peak hour to average day demand factor of 4.4 was used. For the WUMP, the diurnal pattern was evaluated as well as recent hourly water usage data to determine an appropriate hourly peaking factor. Due to changes in the city's data management, hourly data are only available back to June of 200620. Figure 5-8 shows the diurnal water usage pattern in Boulder during summer (June through August) and winter (November through February). The diurnal curve is substantially different depending on the time of the year. In the summer, the peak hour occurs between 5 and 6 in the morning at a rate of about 40 MGD, presumably when irrigation water usage is highest. Water usage peaks again in the evening, between 9 pm and midnight. During the winter, water usage is steadier throughout the day, with peak water usage of about 15 MGD occurring mid-morning. 45 40 Winter 35 Summer i 30 25 tw 20 M 15 L 10 5 0 0 2 4 6 8 10 12 14 16 18 20 22 24 Hour of day For the period June 2006 through May 2010 the 95th percentile hourly water usage was 35.3 MGD, a peaking factor compared to the average day of 2.1. Since a relatively short period was analyzed (relative to the 1 in 20 year reliability criteria), the 99th percentile statistic was calculated as a point of reference. The 99th percentile of hourly water usage was 44.9 MGD, a peaking factor of 2.7. Since this peaking factor is close to the maximum day peaking factor, the historical data was reviewed again during the hydraulic modeling workshop held on July 1, 2010. Data review revealed a few peak hour data points above the 2.7 peaking factor. As a result, a peak hour peaking factor of 3.6 was selected as conservative for the planning period purposes. Table 5-6 presents a summary of the planning period peaking factors used for evaluation and analysis throughout the master plan. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-9 i ible 5-6. Pl<. - i- peOor! 0-kirq Factors Period Peaking Factor' 2010 2015 2025 2035 Buildout Minimum Day 0.6 0.6 0.6 0.6 0.6 Minimum Month 0.6 0.6 0.6 0.6 0.6 Peak Month 2.05 2.05 2.0 2.0 2.0 Peak Day 2.6 2.6 2.6 2.6 2.6 Peak Hour 3.6 3.6 3.6 3.6 3.6 To be multiplied by average daily flow (ADF) to obtain flow value Table 5-7 presents a summary of the planning period flow rates based on the peaking factors from Table 5-6. Period Flow (MGD) 2010 2015 2025 2035 Buildout Minimum Day 10.1 10.3 10.8 11.4 12.8 Minimum Month 10.1 10.3 10.8 11.4 12.8 Peak Month 37.8 38.79 39.6 41.8 47.1 Peak Day 48.0 49.2 51.5 54.3 61.2 Peak Hour 66.5 68.1 71.3 75.2 84.7 5.6 Water Conservation Program Based on recommendations in the 1988 City of Boulder (city) Raw Water Master Plan (RWMP) and 1990 Treated Water Master Plan (TWMP), in 1990 City Council approved implementation of an enhanced water conservation program with the primary purpose of deferring the expansion of the Boulder Reservoir Water Treatment Facility (WTF). The Water Conservation Program was formally established in May 1992 to direct the efforts of reducing overall water consumption within the City of Boulder (Boulder) and specifically to reduce summer peak demand usage. The Water Conservation Program was designed to promote water conservation through voluntary measures that create a greater public awareness of the resource and encourage wise water use. The Water Conservation Program was adopted by City Council as a single staff (one full-time equivalent) program and is currently managed under the Utilities Department in the Water Quality and Environmental Services (WQES) Group. Since the Water Conservation Program was initiated in 1992 it has been expanded beyond the initial scope of the program to address additional water conservation initiatives and support additional programs such as the popular water conservation rebate program. The Water Conservation Program is supported under City of Boulder (city) Boulder Revised Code (BRC). Changes to BRC regarding water conservation will be proposed to City Council in early 2011, as follows: Section 11-1-48: Water Conservation Program The water conservation program will be an ongoing effort to promote efficient water use that is compatible with the city's water supply system, water resource management strategy and the valises of the community. The water conservation program will create incentives for water conservation by users of the water supply of City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-10 the city, to pi,event unnecessm y depletion of the raw and treated water- supply of the city, to attempt to supply a continuing level of satisfactory service to existing water utility customers, and to insin°e the city's ability to meet the present and future basic water needs of the city's i°esidents and will be implemented pursuant to the 00; of Boulder Water Conservation Plan. Proposed changes to BRC Section 11-1-52 - Enforcement of Drought Response Measures, also supports the Water Conservation Program during a declared drought. In June 2008 the Water Conservation Program Supervisor left the city and a process was initiated to fill the vacant position. In early 2009, prior to filling the Water Conservation Supervisor position, city management recommended not filling the position due to budget concerns and to re-evaluate filling the position in 2010. Currently, the Water Conservation Supervisor position is still vacant due to on-going budget concerns and the Water Conservation Program is being implemented through support from multiple WQES Group staff. Reducing water demand through water conservation efforts improves the city's ability to fill reservoirs in the spring reservoir fill season and reduces the rate of reservoir drawdown during the city's reservoir release season from about August until May. Therefore, water conservation efforts during certain times of the year enhance the city's ability to weather droughts by maintaining adequate storage reserves. However, in any given year, once the city's storage reservoirs are full and the city is meeting water needs through direct diversion of water from the stream, reductions in water demand from water conservation efforts have no benefit for sustainability of the city's raw water supply. Savings from water conservation during the direct flow period reduces the amount the city diverts, but the city cannot store the savings for later use or assign the saved water to another use. Streamflow below the city's intakes would increase until the water reached the next headgate of an in-priority water rights owner able to make use of the water (SWMP, April 2009). The 2000 Water Conservation Futures Study developed baseline water demands for the city's urban service area for the year 1995 based on monthly metered end use data. Various adjustments were made to accommodate factors such as annual weather variations and unaccounted-for water- Total demand and demand by various end use categories (sectors) was projected from the base year of 1995 through 2020. The study also developed demand projections for a number of water conservation scenarios of varying degrees of intensity- City Council selected the Water Conserv ation Futures Study Comprehensive Conservation Scenario which was designed to address both indoor and outdoor water use patterns. The scenario was intended to result in a 10 percent reduction in total water use at build-out (approximately 2025) when compared to the Water Conservation Program structure that was in place in 2000, and about a 25 percent overall reduction in water use when compared to no conservation program being in place. Adoption of the Comprehensive Conservation Scenario required substantial revisions to the Water Conservation Program and an increase in annual funding to support various water conservation initiatives. The city's 2000 TWMP estimated water use reduction by sector to achieve the overall water use reduction goal set by the 2000 Water Conservation Futures Study Comprehensive Conservation Scenario. Utilizing elements of the Comprehensive Conservation Scenario, baseline water usage defined as 1994 through City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-11 1996 water use, and population and employment projections, water use reductions by sector were developed. Water use reduction targets, by sector, are as follows: • 22 percent reduction in per-meter use for the single-family residential sector • 26 percent reduction in per-meter use for multifamily residential sector • 14 percent reduction in per-meter use for the commercial/industrial sector • 1 percent reduction in overall municipal use • 15 percent reduction in unaccounted-for water Achieving these targets was expected to reduce the overall annual water demand by approximately 19 percent at build-out as compared to water use at build-out absent the Comprehensive Conservation Scenario. The emphasis of the Water Conservation Program was modified to focus on water use reductions in each sector and resources were allocated as needed. An additional water conservation goal of the 2007 implementation of water budget based rates was to have all water customers in the service area stay within their allocated water budget. The city had a flat water rate structure until 1988 when it first implemented as an increasing block rate structure. In December of 2004, the City Council adopted a new structure, the water budget rate structure, which was implemented in 2007- Beginning in January 2007, the city converted to a five-block rate structure based on established "water budgets" for each type of customer. As the amount of water use increases and moves into the next block, the cost per thousand gallons increases. The water budget approach is a unique method of computing monthly water bills by giving each water customer monthly water budgets that are tailored to reflect each customer's indoor and outdoor water needs. The Water Conservation Program has been integral in assisting water customers with staying within their water budget by offering indoor and outdoor water conservation rebates and outdoor water audits. Some examples include supporting low-flow fixtures indoors and water efficient outdoor irrigation. In 2009, the city updated the Water Conservation Program Water Conservation Plan to meet the requirements set by the Colorado Water Conservation Board (CWCB). The Water Conservation Plan was submitted to the CWCB for review and was approved by CWCB in August 2009. The Water Conservation Plan serves multiple purposes including: 1) complying with state law requiring water providers delivering 2000 acre-feet or more of retail water to submit a water conservation plan to the CWCB; 2) provide guidance in updating and implementing the city's Water Conservation Program in a way that is compatible with the city's water supply system, water rights, existing water conservation programs, water resources management strategy, and values of the community; and, 3) allow the city to pursue grants from the CWCB to support water conservation projects with some of the city's largest water users. The Water Conservation Plan includes information regarding the city's historical and projected water demands and supplies. It also includes a discussion of the city's water conservation goals and the greatest potential water savings through conservation, as well as a portfolio of conservation measures and programs. Implementation and monitoring methods are also addressed to assess the effectiveness of each measure and program. The Water Conservation Program is currently being implemented with a primary focus on the following activities and program. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-12 5.6.7.1 Rebate Program The water conservation rebate program has been in place since 1997 and includes residential and commercial rebate opportunities. Rebate items include low-flow toilets (128 gallons per flush or less), high efficiency (27 gallons per load or less) clothes washers, and residential and commercial irrigation systems and soil amendments. The annual rebate totals have ranged from a low of 112 rebates in 1997 to a high of 676 rebates in 2003. Since 2000, the Water Conservation Program has tracked rebate totals by rebate type and a summary is provided in Attachment A. 5.6.7.2 Center for Resource Conservation The Water Conservation Program contracts with the Center for resource Conservation (CRC) to provide assistance with three water conservation programs. A summary of these programs, and results for the year 2009, is provided below. • Slow the Flow Program. This program includes a free residential irrigation water audits for Boulder residents receiving city water. In 2009, 98 residential irrigation audits and five Home Owner Association (HOA) irrigation audits were performed in the City of Boulder. • Water Wise Plant Sale, which includes Garden-in-a-Box, Garden Essentials and Trees Across Boulder. > Garden-In-A-Box is a program that provides low-cost, professionally designed, pre-planned xeric gardens to Boulder residents. Three designs are made available to choose from. Each garden includes a design layout, 30 or more plants and some helpful tips about xeriscape gardening, including planting and maintenance instructions for all of the plants. In 2009, 159 Garden-In-A-Box were sold. > The Garden Essentials program takes the Garden-in-a-Box concept one step further, and in addition to supplying the plants, CRC also offers the option to purchase low-cost mulch, compost, and drip irrigation systems, all of which are necessary components for creating a successful water-wise garden. In 2009, 106 Garden Essentials kits were sold. > Through the Trees Across Boulder program, eight different tree species chosen by the city's Urban Forestry Department for their ability to thrive in Boulder, are made available to Boulder water customers. In 2009, 90 trees were sold. • Water Wise Landscape Seminars. The Water Wise Landscape Seminar series focuses on helping Boulder residents increase water use efficiency, adhere to best management practices, and reach conservation goals. In 2009, 170 Boulder residents attended the Water Wise Landscape Seminars. 5.6.7.3 Public Information and Outreach In 2009 water conservation information and outreach efforts were revised to focus less on Water Conservation Program advertising through magazines and journals and more on working with the city's larges water users, teaming with other local efforts and enhancing public education and outreach in the community. Advertising efforts are evaluated each year to ensure the water conservation message supports current water conservation goals and the location of advertisements (magazines, etc.). Outreach efforts vary from direct contact with the public through school programs and the annual Boulder Water Festival to providing specific water conservation messages utilizing city utility bill inserts. Substantial outreach efforts have also focused on two of the city's largest water users, the University of Colorado (CU) campus and the Boulder Valley School District (BVSD). Multiple meetings have been held with CU facilities and sustainability staff to identify joint city and CU efforts to implement and promote water City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-13 conservation on and off campus. Water conservation efforts have focused on promoting rebates and providing educational information and presentations. The city is also working with BVSD on a grant funding opportunity through the CWCB utilizing the city's approved Water Conservation Plan. The city has also coordinated with groups like Boulder County Longs Peak Energy Conservation program to implement water conservation into Energy Sweeps Programs held in the City of Boulder. The Water Conservation Program is currently working with the city's Local Environmental Action Division to continue developing partnerships which help synergize the overlap between energy and water conservation efforts. 5.6.7.4 Commercial, Industrial and Institutional Water Use Study Of the city's approximate 29,000 water billing accounts 2,000 are Commercial, Industrial, and Institutional (CII) accounts. Based on 2004 through 2008 water use data, the CII customer class used an average of 26 percent of the city's total water sales. Compared to the residential sector, less is known about the water use characteristics of the CII sector since it has dissimilar customers with regard to the purpose of water use. The historic lack of benchmark measurements of the quantity of water used, or needed, for a particular type of CII customer makes it difficult to design a CII water efficiency program that can be integrated into a water billing system, such as the city's water budget rate structure, or a water conservation program. In late 2009 city staff initiated a phased approach to completing a CII water use study to better characterize water use patterns and evaluate possible options for developing sector-specific water use efficiency benchmarks. Phase I work included the following: • Compilation and Review of Existing CII Water Use and Benchmark Information • Evaluation of the City of Boulder's Utility CIS Billing System CII Sector Information • Select CII Sector Sub-Categories for Further (Phase II) Evaluation Phase II will be initiated in early 2011 and will focus on evaluating data and information gathered under Phase I and possibly perform a Pilot Study to collect account-specific data for the selected sub- categories. Efforts will focus on gathering additional information from a sub-set of the selected sub- categories through site visits and audits and developing and implementing methodologies to evaluate available data and information to develop appropriate efficiency benchmarks. Benchmarks should reflect the quantity of water used in specific CII sector sub-categories which allow the business to perform its required functions, while incorporating business growth, with the efficient use of water. The following activities will also be considered under Phase II. • Identify customers within each sub-category evaluated that may currently be implementing efficient water use practices and are already at, or close to, an efficiency benchmark level of water use. • Evaluate appropriate normalizing factors to be used in evaluating collected data and information. Normalizing factors should focus on data and information from multiple customers in the same sub-category that can be used for other accounts in the same sub-category. • If possible, disaggregate indoor water uses into individual end-use categories (toilet/urinal flushing, sinks, showers, etc-). • Evaluate options for developing efficiency benchmarks for CII sector sub-categories. • Develop efficiency benchmarks for CII sector sub-categories. • Determine CII sectors and or sub-categories for additional city water conservation support- It is anticipated that Phase II will be completed in late 2011, and the project completed in 2012. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-14 5.6.7.5 Grant Funding Pursuant to the CWCB's approval of the city's Water Conservation Plan in 2009, the Water Conservation Program is now eligible to apply for CWCB Water Efficiency Grants. The CWCB offers four types of Water Efficiency Grants, including: • Water Conservation Planning Grants • Water Conservation Implementation Grants • Drought Mitigation Planning Grants • Water resource Conservation Public Education and Outreach Grants The city plans to pursue CWCB grants as opportunities arise. Currently, the city is working to support the CII water use study along with goals outlined in the Water Conservation Plan by applying for a Water Conservation Implementation Grant from the CWCB. The proposed project will work with Boulder Valley School Districts, the city's fourth largest water user, to reduce water consumption in two key schools. Water conservation in Boulder has been a major driver in the city's ability to defer capital improvements at water treatment facilities and to achieve water savings goals that support the Comprehensive Conservation Scenario developed as part of the 2000 Water Conservation Futures Study, and adopted by City Council. Water conservation efforts, along with other factors such as climate and the Water Budget Rate Structure, which incorporates water conservation measures, have impacted water use and the need for capital projects. 5.6.8.1 Status of Water Conservation Goals Baseline water use and water conservation goals, by sector, were developed as part of the 2000 TWMP and the overall water use reduction goal set by the 2000 Water Conservation Futures Study Comprehensive Conservation Scenario. Percent water use reduction goals, by sector, are discussed in Section 4.3, above. Table 4-1 summarizes the baseline water use, water use conservation goal and current water use. For most sectors the conservation goals have already been exceeded. Total municipal water use has slightly increased in total, but has decreased per capita. Although it appears that the single family sector goals have not been met, this is likely due to differences in how the population is counted compared with how water use is tracked. The initial projection for meeting the water conservation goals was by buildout, which was defined as the year 2025 in the 2000 TWMP. Table 5-8, Baseline and Current latter ->age Compared to Conservation Goal: (gallons per Sector Baseline' Conservation Goal Currents Units Single Family Residential 148 115 117 Gallons per person per day Multifamily Residential 90 67 62 Gallons per person per day Commercial/ Industrial 62 53 50 Gallons per employee per day Municipal 646,000 640,000 665,000 Gallons per day (galluns 1,er day) Unaccounted for 1,695,000 1,440,000 1,110,000 Gallons per day Total production 186 149 147 Gallons per capita per day *For additional detail on water use and water use projections see Volume 2, Section 5, of the Water Utility Master Plan. 1 Baseline water use is based on water use from 1994 through 1996. 2 Current water us is based on water use from 1996 through 1999. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-15 Achieving the water conservation goal for each sector is expected to generate an overall water use reduction of 19 percent at build-out as compared to water use at build-out absent the Comprehensive Conservation Program. Per capita water use at build-out is expected to be greater than 2007 levels due to increases in the jobs to population ratio, but will be less than without the Water Conservation Program_ 5.6.8.2 Delays in Capital Improvement Projects In the 1990 TWMP recommendations were made to increase the Boulder Reservoir WTF capacity by 10 million gallons per day (mgd) by 1994 at a cost of over $12,000,000 if water conservation measures were not implemented. Through implementation of effective water conservation measures, and other factors, such as water budgets and weather, expansion of the Boulder Reservoir WTF was delayed until 2005 when the city completed an expansion from 8 mgd to 16 mgd firm capacity. This was an 11 year delay in capital costs to expand the WTF and the expansion is expected to meet City of Boulder water needs through build-out. Delays in capital improvements at the Betasso WTF have also occurred. An overarching goal for future Water Conservation Program efforts is to tailor water conservation to the city's unique water system and focus on the nexus between water and energy conservation, and to support water related environmental enhancements. At the tap level this will include a re-evaluation of current programs to align them with stated goals. On a planning level this will include Water Conservation Program support for using less west slope water supplied through the Colorado Big Thompson and Windy Gap projects which minimize energy intensive west slope to east slope water transfers and help conserve westslope water. Water conservation measures that support maximizing raw water use from the Boulder Creek watershed will also be considered to support additional hydroelectric power generation throughout the city's system. It should be recognized that future water conservation measures of this kind may be limited due to the city's water rights, structure of the raw water system and location of water treatment facilities. Fill Vacant Water Conservation Supervisor Position. Since June 2008, the Water Conservation Supervisor position has been vacant and the Water Conservation Program has been jointly managed by multiple WQES Group staff. Due to budget constraints, approval to fill the Supervisor position has not been granted and the Water Conservation Program is being implemented at a reduced level. In the August 2010 the Colorado Water Wise Guidebook of Best Practices for Municipal Water Conservation in Colorado was released and was developed to promote and facilitate the efficient use of water in Colorado and was funded by the CWCB. One of the 14 Best Practices in the guidebook is to have a Conservation Coordinator which is responsible of managing an entities water conservation program and implementing water conservation efforts to meet water conservation goals of the community and the State of Colorado. For larger communities, such as Boulder, it is recommended that the Conservation Coordinator position be a full time position. It is recommended that the city hire a full time Water Conservation Program Supervisor to adequately manage the Program and effectively implement water conservation measures in Boulder. The Water Conservation Supervisor will have the responsibility of making sure the Water Conservation Program meets the current and future water conservation needs of Boulder and the city. Continue to Fund the Water Efficiency Fund. The Water Conservation Program Water Efficiency Fund was initiated in 2003 and implemented through 2009. The goal of the Water Efficiency Fund was to provide matching funds for city projects which focused on water savings. All city Departments were eligible for funds at a rate of a 50/50 match. In 2010, the Water Efficiency Fund was eliminated due to limited funding, but was reinitiated in 2011 at a level of $50,000. It is recommended that the Water City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-16 Efficiency Fund continue to be funded at a minimum of $50,000 per year. The program should also be evaluated annually and modified as needed to meet city facility water use goals. It is also recommended that a funding matrix be developed to prioritize projects and distribution of the Water Efficiency Fund budget. The matrix can be based on factors such as total water savings, block 4 and 5 water users, achieving specific water savings goals (department or city-wide), size of the project (financially or physically), ability to further leverage the project for additional water savings and the potential for energy savings. Evaluate Municipal Water Use and Support Water Use Reduction Measures. In 2008 water budgets were developed for municipal (city) accounts, which include city facilities, departments, divisions, work groups and or funds. Currently, municipal accounts are not charged for water, but the goal is to have all municipal accounts stay within their water budget. A pilot project was initiated in mid 2008 to evaluate municipal account water usage compared to water budgets with an emphasis on encouraging efficient operations and reduce water usage, specifically in blocks 4 and 5 (i.e., penalty blocks). The Water Conservation Program should assist those city facilities that have water use in blocks 4 and 5 through technical and public awareness support, and utilize the Water Efficiency Fund. Evaluate Existing Water Conservation Rebate Program. Currently, the city provides rebates for residential and commercial accounts for the following items: • Toilets (HET- high efficiency toilets with 1.28 gallons per flush, or less) • Washers (high efficiency washers with 27 gallons per load, or less) • Irrigation systems (multiple components) Since 1994, only low flow toilets with a 1.6 gallon per flush (gpf) rate or less have been available through retail sale. An evaluation should be completed to determine if the city should continue to offer toilet rebates since higher water use toilets are no longer available through the retail market. The evaluation should consider, to the degree possible, whether the number of old toilets (greater than 1.6 gpf) being replaced would decrease if rebates were not available- A process should be developed to track what type of toilets (gallons per flush) are being replaced when a rebate is requested. This information will help make a determination of how many low flow, or high efficiency, toilets (including WaterSense approved or waterless urinals) are being replaced and a rebate requested, and whether rebates should be offered for the replacement of a toilet with similar or equivalent water use. Currently, a large majority (85 percent) of the annual water conservation rebates, support indoor water conservation. Shifting the rebate, and general Water Conservation Program focus, to outdoor water savings should be evaluated since peak water use is driven by outdoor watering during the irrigation period. Further indoor water use reductions can be considered "passive savings" that could continue with little or no rebate support due to the fact that most water using devices currently available are already considered to be water efficient. Consideration should also be given to adding additional rebate options, which could include: • Low-flow shower heads • Faucet aerators • Efficient landscape design • Rain sensor-based controls for irrigation systems City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-17 • Commercial or industrial water audits conducted by a certified professional • Low-flow Pre-Rinse Spray nozzles • Prevention of Once-Through Water Use (i.e., Cooling Towers, Ice Makers, etc.) Automate Existing Water Conservation Rebate Program Process. Water conservation program rebates are a known cost and as such can be budgeted for and evaluated by a cost-benefit ratio. However, rebate processing time represents a hidden cost inherent in each rebate processed. Staff estimate that each rebate takes an average of 20 minutes to process when standard rebate processing are combined with the multiple rebates which are incorrectly filled-out or lack the necessary attachments which often requires lengthy customer follow-up. Additionally, there are costs associated with the financing department "cutting" rebate checks to customers. Reducing these processing costs would maximize Water Conservation Program effectiveness as time and money currently spent on rebates could be recaptured and used to support additional programs. Currently, the Water Conservation Program is evaluating a computer program which would allow customers to complete rebates on-line and would require customers upload necessary documents before a rebate could be submitted. Additionally, the Water Conservation Program is working with the city's Financing Department to see if rebates can be added as credits to customer's accounts to eliminate costs associated with sending rebate checks to customers. It is recommended that the Water Conservation Program move forward with both efforts to increase the efficiency of the water conservation rebate program. Evaluate Control of System Water Loss. The city's water distribution system water loss rate is approximately 10 percent. Currently, there are no state or national standards for water loss and water loss goals are typically set to meet in-house goals or standards. The CWCB, in their Statewide Water Supply Initiative 2010 Municipal and Industrial Water Conservation Strategies Report, recommends that "real" water loss should be in the range of 6 to 7 percent. Water losses can be considered a "real" water loss (leaks or other problems in the system) or an "apparent" water loss (meter inaccuracy, unauthorized consumption, data evaluation errors), and the methods of correction will differ between the two types of losses. The benefits of reducing system water loss are multiple, including financial savings, raw water conservation, enhanced drought preparedness and setting an example for the public. It is recommended that the Water Conservation Program support (staff support or monetarily) conducting a leak detection study initially focusing on known water loss areas within the distribution system. Utility costs for water loss control vary depending on the level of lost water and the cost of repairs to reduce or eliminate water leaks. It is suggested that a two step process be implemented, which includes conducting a Water Audit then conducting a Water Balance. It is recommended that the American Water Works Association (AWWA) 2009 Water Audits and Loss Control Program Manual of Water Supply Practices (M36) be used as guidance for performing a Water Audit and Water Balance whether the study is conducted internally or contracted. A free TmExcel-based program from AWWA is available for internal, or contractor use, and can be used as a starting point in any water loss study. Develop a Monitoring, Evaluation and Reporting Program. To ensure that the Water Conservation Program is accomplishing established goals, a monitoring evaluation and reporting program should be established. Efforts should focus on quantifying water savings through the water conservation rebate program, for both indoor and outdoor rebates, and outdoor water audits performed through the Slow-the- Flow Program. Reports should be developed annually and submitted to Public Works Utilities and the Water Resources Advisory Board. The reports should include recommendations for making adjusts to the Water Conservation Program to meet the needs of the city and City of Boulder water customers. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-18 Evaluate and Enhance Raw Water Irrigation Opportunities. Additional opportunities to use raw water for irrigation purposes, for the city and non-city entities, should continue to be evaluated in a joint effort with the city's Water Resources Group and the Parks and Recreation Department. Initial steps have already been taken to identify potential sites for raw water irrigation by matching a location, such as a park, with a stream or irrigation ditch in close proximity. In some cases the available water right may not allow the intended raw water irrigation use and legal action may be required to change the use. Water Conservation Program efforts, and the use of the Water Efficiency Fund, should focus on projects that would require limited legal action, if possible. Develop City-Wide Water Conservation and Water Conservation Program Goals. Water conservation is not an end in itself and water providers should specify how water conservation fits with the needs of the water system and its customers. Often this means setting goals for achieving water savings that an entity identifies as being either: • Required to balance future water demand with future available water supply; or • Cost-effective based on the incremental or marginal costs of new water supplies. Other benefits of water conservation may be incorporated into goal statements. In all cases, water conservation goals should provide a "yardstick" for measuring the effectiveness of the conservation plan's implementation. Setting goals related to the amount of water that "will be saved" through future conservation efforts is a requirement of the Water Conservation Act of 2004. Goals should be stated in terms that are measurable, achievable, and reasonable, and have a specific time frame plus be relative to water system conditions and anticipated water demand by sector. As discussed in Section 4.6.1 above, the city is close to achieving, or has already achieved, water use goals by sector which were developed for a 2025 build-out date. The Water Conservation Program has also developed and implemented successful water conservation strategies that have meet the initial intent of the Water Conservation Program. New city-wide water use goals, by sector, should be considered and support updated water demand forecasting that will be performed using results of this Water Utility Master Plan. Water use goals should also consider, and account for, refinements to water budgets for the multi family and commercial, industrial and institutional sectors that are currently being evaluated. Community involvement should also be part of the water conservation goal setting process and can involve representatives of various groups in the community (or stakeholders). Community involvement emphasizes an open process that involves potentially affected groups so that they can have an opportunity to express their interests and concerns. Involving the community in goal development also serves an important public education function. Moreover, it is widely believed that involving the community in developing goals, as well as in the implementation process, can greatly enhance the success of conservation programs. Members of the community who might be interested in water conservation include: • Residential water consumers Business and commerce groups • Commercial water consumers • Recreational water users • Industrial water consumers • Agricultural users • Wholesale customers • Educational institutions • Environmental groups • Government agencies In addition, community participants also can have an ongoing role in the implementation of the selected conservation measures and programs. Ongoing involvement can help maintain and build support for achieving conservation goals and can help "get the word out" about the conservation effort. Participants can act as a focus group for exploring specific conservation measures and/or programs and can also City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-19 provide valuable linkages to key groups-consumers, businesses, and institutions-who might be involved in implementing certain conservation measures. L:bie 5-9. v'vlater Pr, C; M, 2' 2100+ `t' B"C Llop, 100 Year 2000 2001 2002 2003 2004 Total Total Total Total Total Rebate Type Dollars Number Dollars Number Dollars Number Dollars Number Dollars Number Residential Washer $34,200 342 $38,900 389 $29,625 390 $38,475 513 $30,000 400 Commercial Washer $0 0 $0 0 $0 0 $1,125 15 $450 9 Residential Toilet $0 0 $0 0 $0 0 $6,000 120 $5,500 110 Commercial Toilet $0 0 $0 0 $0 0 $0 0 $450 18 Irrigation System and $2,505 15 $5,428 23 $5,295 17 $15,265 28 $7,300 72 Soil Supplements Total for Year $36,705 357 $44,328 412 $34,920 407 $60,865 676 $43,700 609 Year 2005 2006 2007 2008 2009 Total Total Total Total Total Rebate Type Dollars Number Dollars Number Dollars Number Dollars Number Dollars Number Residential Washer $21,225 284 $22,625 302 $23,775 317 $31,050 414 $24,075 321 Commercial Washer $23,625 189 $9,600 18 $0 0 $750 3 $550 4 Residential Toilet $300 4 $1,650 21 $4,275 55 $12,700 141 $15,520 207 Commercial Toilet $0 0 $0 0 $738 7 $750 2 $2,900 16 Irrigation System and $4,932 21 $8,039 54 $14,308 54 $12,259 82 $8,921 72 Soil Supplements Total for Year $50,082 498 $41,914 395 $43,096 433 $57,509 642 $39,656 620 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 5-2 6 Finance and Administration The following sections present a discussion of various administrative and financial aspects of the City's Water Utility. 6.1 Sources of Funds The Water Utility is funded primarily through monthly user fees which account for approximately 73% of annual water revenues. Other significant revenue is derived from plant investment fees, interest on investments, sale of hydroelectric power and bond proceeds. The sources of funds are depicted in the figure below. .-iguie Q-i. Aveia, Utility Service Charges $19,569,955 73% Hydroelectric Revenues $1,921.749 7% Interest/Other' $2,039,393 8% Development Fees $3,297,577 12% *Excludes 2006 Lakewood Settlement of $19.5 million, and 2007 Bond refunding of $25.9 million Monthly water charges consist of a fixed service charge that is based on meter size and inside or outside city classification, and a consumption charge based upon metered water use. The consumption charge consists of five rate blocks. As the amount of water use increases and moves into the next rate block, the cost per thousand gallons of water increases. This increasing block rate structure is used to encourage the efficient use of water. In 2007, the city began using monthly water budgets to determine the appropriate rate block to be used for billing. A monthly water budget is developed for every customer using criteria such as number of people in the household, historic usage and specific irrigable area. The budgets for residential customers and irrigation-only accounts are shaped throughout the year to reflect outdoor watering patterns. Water City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-1 use above a monthly water budget is billed at increasingly higher rates than water use that is within a monthly water budget. The block rate structure for the quantity charge portion of the water bill is shown in the following table. Table 6-1. t_ es - Block Rate Structu,e Rate Per 1,000 Gallons Water Usage Gallons Billed in Each Rate Block Block 1 '/4 the Block 2 Rate Usage u to 60% of the month) budget Block 2 Block 2 Rate Usage between 60-100% of the month) budget Block 3 2 times the Block 2 Rate Usage over month) budget u to 150% of month) budget Block 4 3 times the Block 2 Rate Usage between 150% and 200% of month) budget Block 5 5 times the Block 2 Rate Usage over 200% of month) budget The city of Boulder currently has 28,500 water accounts that are identified by four major customer classes or account types. Accounts by customer class are shown in the figure below. figure 6-2. Number and rercent of v" Commercial/ Metered Irrigaiton Industrial 1,600 2,100 (6%) Multifamily Residential 2,500 (9%) Single-Family Residential 22,300 (78%) Plant Investment Fees (PIFs) are system development fees charged to new and existing customers who need additional utility service to recapture initial capital investments into the water utility infrastructure. In 2009 PIF revenues accounted for 12% of annual water revenues. PIFs were recently reviewed in 2008-2009 and were revised to reinforce the goals and objectives of the water budget rate structure. The water utility infrastructure inventory and valuation was also reviewed and updated. PIFs meet the requirements of Colorado Revised Statutes for Impact Fees 29-20-104.5). PIFs are established using the buy-in methodology which results in new customers paying their proportionate share of the costs of facilities required to serve them. The fees are dependent on the capacity required to serve a customer and the unit cost of existing facilities expressed as dollars per unit of capacity. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-2 The water utility also receives about $2 million annually from the sale of hydroelectric power that is generated from its eight hydroelectric facilities. Other miscellaneous revenue sources include interest earnings, sale of goods and capital assets and special assessments. Major capital projects and improvements are sometimes funded by issuing revenue bonds. Comprehensive rate reviews by an outside consultant occur approximately every five to seven years: • Water Rate Study (as part of the implementation of water budgets), Red Oak Consulting, 2006 • Plant Investment Fee Study, Red Oak Consulting, 2008 6.2 Administration The Water Utility is administered by the City's Public Works Department - Utilities Division. Primary work groups in the Water Utility include: • Water Resources and Hydroelectric Operations • Water Treatment Operations • Water Quality and Environmental Services • Utilities Planning and Project Management • Utilities System Maintenance Other work groups in the Public Works Department that support the Water Utility include. • Information Resources • Finance and Analysis (includes Utility Billing) • Engineering Review • Asset Management The figure below presents the organizational structure for work groups that support the Water Utility. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-3 Figure 6-3. Public Works Department Organization Structure i?fcrutiYe Dircclor of PUhiic %%Crks - - 41aur+'c.nitalt - I r I I I I Public Wirksll liiiel s Public N1'urks/1-ranwiruriulion I I \ed 1', illi:en, 1.1a.c% A'irlrrr': I ~ r I I r I r I a~iryrrtln 3\:trsr %%strr Nrariurir% 11Att•r 3l.lulirk 1 ri ill" 14ennin2 I Inf,iralilirr° Fitr. -A n I--J-rl..6- I rralmrnl \ Ilydr!Irlrrlrir F arnn mcnt~l .4 Pr+I rrl I 1lrrir 1{rwurtr> %nrlt.is 1 & I tilil% I . :x.151 iil ._i..l IIhn 'I:. ♦r r. nc. I-ro. inrrrin, Khilil4rllamrr I M;1 Inrl' Irnh ;.n:!lrr 'S ILLI'v- I 231 1•I% ;i.; All :_t 111-~ 111.''111 111 It:_i it - adni:da: r -~I ill .IA' l I Grr.r.rvr N'.Mr Ile"t, Rr.or•. iaa rin., G lrralm.r i. IitQFn 1 I N .,.A. u'.ter ~ ' I ~~6 rla.lr. rah 0... .arr I 1R~[t - I...M.L I 1_ ,urr.~r R- xNy 4 ~Li.r ~S n. rr.l.a+ I 11.6 c¢ lamb SIR..I '1..n fyr~ 13rylpl.ln kn.~a. w - I- rrpar PV'e I ROM 11 Sh3 ~rla n.l _ L 1'-p FI.w rtn.itr ►Lr...r.6 `..[1 ?ta i- A 1•drreRrrnir r.J.rr;J _ r,rt r..• ' I I ` rr.cn.ba one reKr~ _ `r.e.a.~v 1 I ~hN P<rni:, til nna_tmrell - rlrrr.li.m I r~r~ J w.4u.rr r I .u ....~IrS Sr+ wlMr krrlrn w.r~..are I I I i•e.r, i Aken I I tIl.rl{ a.lyd rrasar~a r I I I I I I I I 1 I , City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-1 The water utility, which is predominantly self-supported by user charges, is established as an enterprise fund designed to separately finance and account for its facilities and services. Per the Boulder Revised Code, it is intended that the Water Utility shall at all times and in all ways conduct its affairs so as to continue to qualify as a "water utility enterpise" within the meaning of Section 37-45.1-102, C.R.S. and as an "enterprise" within the meaning of Article X, Section 20 of the Colorado Constitution. Specifically, but not be way of limitation, the Water Utility is not authorized and shall not receive ten percent or more of its annual revenue in grants. Funds are allocated to the various functions of the Water Utility as summarized in the figure below. Maintenance Debt" $2,664,612 $8,261,808 Water 10% Quality 30% $1,120,785 4% Water Treatment Transfers $3,958,126 $1,295,936 14% Water Resources $1,985,129 Administration Capital 7% $780,312 Improvements $6,896,065 Engineering 3% 25% $506,763 *Excludes 2007 bond refunding of $30.3 million Assets are compiled and updated periodically to support financial reporting requirements. The following table summarizes the asset valuation of the City's Water Utility as of 2007. Asset Valuation Accumulated Replacement Cost Description Original Cost Replacement Cost Depreciation at RC Less RCLD Water Rights Land $30,654,000 $30,654,000 $30,654,000 Water Rights $363,419,000 $363,419,000 - $363,419,000 Total $394,073,000 $394,073,000 $0 $394,073,000 Land $238,022,704 $238,022,704 - $238,022,704 Water Services $96,908,414 $120,259,939 $21,890,692 $98,369,247 Boulder Reservoir WTP $28,129,023 $59,234,126 $25,075,720 $34,158,406 Storage Reservoirs $7,180,093 $42,774,165 $25,072,467 $17,701,699 Hydroelectric Plants $13,558,209 $57,670,110 $33,438,756 $24,231,235 Betasso WTP $42,734,974 $106,066,814 $51,423,486 $54,643,328 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-1 Asset Valuation Accumulated Replacement Cost Description Original Cost Replacement Cost Depreciation at RC Less RCLD Hydrants $5,426,832 $14,550,252 $6,437,704 $8,112,549 Vehicles $0 $0 $0 $0 Valves $3,728,665 $9,764,470 $4,340,560 $5,423,910 Treated Distribution Mains $165,053,358 $480,759,569 $226,749,107 $254,010,462 Treated Water Storage Tanks $4,781,553 $29,685,371 $20,582,371 $9,103,000 Treated Water Pump Stations $415,303 $1,398,135 $1,024,939 $373,196 Non-Plant Equipment $0 $0 $0 $0 Buildings $1,050,765 $3,325,622 $1,907,980 $1,517,642 Computers $0 $0 $0 $0 Raw Water Transmission Lines $50,340,446 $652,492,305 $11,899,940 $50,592,365 Total Backbone Facilities $657,330,339 $1,226,003,582 $429,743,749 $796,259,833 Less: Developer Contributions $0 $28,710,120 $13,541,060 $15,169,060 Outstanding Principal $6,460,000 $6,460,000 BRWTP 1996 Revenue Bond: $24,960,000 $24,960,000 Refunding in 2005 2007 Refunding of the 1999 and $22,495,000 $22,495,000 2000 Revenue Bonds Total Contributions and $53,915,000 $28,710,120 $13,541,060 $69,084,060 Liabilities Net System Investment $997,488,339 $1,591,366,462 $416,202,689 $1,121,248,773 The development of PIF unit costs are summarized in the following table. Table 6-3. IF Unit Costs Description RCLD Capacity(a) Unit Cost(d) Unit Cost(e) Raw Water $394,073,000 30,650 acre-feet $14.40 $14.40 Infrastructure Base $384,737,522 20,000,000 d $19.24 $19.24 Infrastructure Peak $342,438,252 35,000,000 d(b, c) $9.78 $6.46 Total Facilities $1,121,248,774 (a)gpd = gallons per day; mgd = million gallons per day. ib)35 mgd represents the system average day of peak month. Used to calculate unit costs for the water budget-based PIFs. IOPeak day capacity is 53 mgd. Used to calculate non-water budget-based PIF options. (d)Water budget unit costs. (e)Non-water budget-based unit costs (Option 1 - Status Quo with New Values and Option 2 - Indoor/Outdoor . This City's fiscal year coincides with the calendar year. Annually staff prepares a six-year planning spreadsheet that includes projected revenues and expenditures for both operations and capital projects. Any future needed increases in monthly utility rates or bond issuances are identified. For the upcoming fiscal year a detailed budget is also prepared. While the six-year planning spreadsheet is presented to City Council, they only adopt or authorize the budgeted expenditures for the next fiscal year. Beginning in 2011 the City-wide budget is developed using a priority-based budgeting approach that scores or rates individual program to community defined results (or goals) to ensure resources are being allocated to areas deemed most important to the community. Budget proposals are reviewed and modified by successive levels of management within the department until a final proposal is approved by the Executive Director of Public Works. The department budget proposal is then submitted to the Water Resources Advisory Board and the Planning Board for their review and recommendation. The City City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-2 Manager considers these recommendations, along with public comment, before submitting the staff recommended budget to City Council, which makes the final determination regarding the budget. While the Water Utility's budget is developed in a cohesive manner (e.g.,programs or projects that affect more than one utility fund or city department), the water utility's budget is entirely independent since it relies upon separate revenues and is maintained as a separate accounting entity. The City Charter and State Law require that an audit of City financial records be conducted each year by an independent certified public accountant. After the audit is complete a Comprehensive Annual Financial Report (CAFR) is finalized. The Water Utility may issue revenue bonds for major capital projects and improvements. City Council can approve the issuance of bonds without voter approval. Revenues from both the City's Water and Wastewater Utilities are typically cross-pledged for repayment of any bonds issued for the Water Utility. Net revenues (total gross revenues minus operating expenditures) before debt service shall be at least equal to 1.25 times its debt payment requirements on an annual basis. These debt service coverage requirements are established as part of the utility's bond covenants. The current ratings for the Water and Wastewater Utility revenue bonds are Aa1 from Moody's and AAA from Standard and Poor's. These are excellent ratings for this type of bond in Colorado. Credit ratings are made after analyzing the credit worthiness of the issuer and the quality of the bond being issued. The ratings are then used by potential buyers of the bonds as one of the determinations in whether they will purchase the bonds or not. The highest investment grade rating given is AAA and the lowest is BBB. Current outstanding bonds related to Water Utility projects are summarized in the following table: Outstanding Principal as of Year bonds paid Project 12/2010 off Imp. to the Boulder Reservoir Water Treatment Facility $4,540,000 2016 Misc projects: Silver Lake Pipeline, Betasso Water Treatment Facility, $17,910,000 2019 Automated Meter Reading and Caribou Ranch Reconstruction and Replacement of Lakewood Raw Water Pipeline $18,705,000 2021 The recommended rate and financial plan for the Water Utility is designed to fund programs and projects, satisfy debt service coverage requirements and maintain required reserves. Reserves are established for bond issuances, employee compensation liabilities, emergencies/stabilization and special purposes. A review of the various financial reserve levels for each of the City's three utilities was conducted in 2006 by Red Oak Consulting and is documented in the Utility Reserves Analysis and Survey, January 2007. The review included a survey of the reserve policies of ten other utilities in the Front Range and Southwestern United States. Based on the study's findings, the water utility maintains a 25% operating reserve and a separate capital reserve. The amount of the capital reserve is based on the minimum annual renewal replacement costs for capital. The capital reserves are initially set at $2,000,000 for the Water Utility. Having both an operating and capital reserve provides greater financial stability and flexibility should emergencies or revenue shortfalls occur. Water revenues can be significantly lower during either a very City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-3 wet or very dry year and it is financially prudent to have reserves available. In addition, bond rating agencies generally favor higher reserve levels and this can contribute to higher bond ratings. In 2005, the American Water Works Association (AWWA) developed a report called Benchmarking - Performance Indicators for Water and Wastewater Utilities: Survey Data and Analysis Report (by Angela K. Lafferty and William C. Lauer) to assess the performance of water and wastewater utilities using a set of identified and tested high-level performance indicators. The indicators are designed to help participating utilities improve their operational efficiency and effectiveness. The AWWA Benchmarking Report provides summary data and comparative analyses of survey data collected from 202 utilities during the years 2003 and 2004. AWWA has continued to publish annual reports which summarize survey data from an increasing number of participating utilities. The current publication used for comparison purposes is the 2009 Benchmarking Report which contains data collected from nearly 350 utilities. These utilities can be broadly categorized according to three criterion measures: geographic region: population size; and type (i.e., water, wastewater, or combined). For the purposes of this study, the city of Boulder is a combined utility in the western region (roughly the Pacific and Mountain time-zones) serving a population of approximately 100,000 customers. Beginning with data collected from 2005, Boulder has participated in the AWWA Benchmarking Study on in every year since. Of the 22 total performance indicators included in the survey, the city of Boulder chose to evaluate 19 which were deemed applicable and attainable. 1. Employee Health and Safety Severity Rate 2. Training Hours per Employee 3. Customer Accounts per Employee & Million Gallons per Day (MGD) Water Delivered 4. Technical Quality Complaints 5. Disruptions of Water Service 6. Residential Cost of Water/Sewer Service 7. Debt Ratio 8. System Renewal/Replacement Rate 9. Return on Assets 10. Drinking Water Compliance Rate 11. Distribution System Water Loss 12. Water Distribution System Integrity 13. Operations and Maintenance Cost Ratios 14. Planned Maintenance Ratio Each performance indicator within this report is presented using median-range charts. AWWA provides summary statistics of industry data which includes the median, 25th percentile, and 75th percentile values. There are both advantages and disadvantages to this method of data reporting. It is advantageous in that it illustrates the industry norm for each indicator. Unfortunately, it lacks the ability to describe absolute high and low values, extreme outliers, or the underlying distribution of the data. The inherent shortcomings of the median-range charts were imposed by the survey in an effort to protect utility confidentiality. Also for this reason, the survey does not provide any correlation between individual data points and utility names. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-4 The most recent performance indicators are summarized in the 2009 Utilities Division Annual Report. In most cases, Boulder's Water Utility falls within the 25th to 75th percentile range. However, in several cases Boulder's performance is outside of this range: • Customer Accounts per Employee - Lower 25th percentile • Disruptions of Water Service - Upper 25th percentile • System Renewal/Replacement Rate - Upper 25th percentile • Return on Assets - Lower 25th percentile • Water Distribution System Integrity - Upper 25th percentile • O&M Cost per Account - Lower 25th percentile 6.3 Metering and Billing The following sections present information regarding the metering and billing program. The City has installed Badger meters on all accounts in the City. The City has a meter testing program in place and tests meters 3 inches and larger according to AWWA policy. • 6" and 8" meters are tested once a year. • 4" meters are tested every two years. • 3" meters are tested every three years In 1996, the City began installing Trace transponders in order to read the meters via radio frequency. In 2006, it was decided to replace the Trace transponders, which were approaching the end of the 10 year battery life and replace them with Orion transponders. The Orion transponders use new technology and allow customers to read their meters with water monitors. The City began offering water monitors to customers in 2008 at a cost of $200 to cover both the cost of the monitor and the upgrade to the new transponder. A new price of $75 has been approved as part of the 2011 budget process since half of the City's transponders will have been upgraded as of 2011. Utility Billing manages approximately 29,000 billing accounts for the approximately 113,000 residents that live within and immediately surrounding the city limits. Meters are read via radio frequency once a month and uploaded into the billing system for bill generation. The Billing Services Representatives visually check and validate the meter reads against a number of criteria, such as zero reads and high/low variance, before releasing them for billing. The City uses Advanced Utilities' Infinity Customer Information System (CIS) for utility billing and payments. This system was installed in 2006 to be used in implementing the water budget methodology in 2007. The billing system generates an electronic billing file sent to an outside vendor for printing and mailing of invoices. The bills are delivered to the post office on the same day they are produced. The City has plans to upgrade to version 3 of the billing system in 2011 in a new virtualized server environment in accordance with the Green Initiative proposed by IT. The City has a planned replacement of the billing system scheduled for 2017 if it is deemed necessary. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-5 In January 2010 the Utility Billing office released a new online bill/payment website called MyBoulderUtilityBill (MYBUB). The website allows customers to view account information, select ebills instead of paper bills and make a payment by credit card. As of November 2010, the City has 3,000 registered users and processes over 1,000 credit card payments a month. In accordance with city code, payments are due ten days after the bill is issued and the city receives payments in several ways. The following summarizes 2009 payments: • Approximately, 12,300 payments per month were processed by a Iockbox processing center at the city's bank. This payment information is uploaded into the billing system and posted to the appropriate account. • Approximately 5,400 payments per month were withdrawn from customers' bank accounts (ACH Debit program) • Approximately 4,000 customers paid by credit card every month with the Recurring Credit card program or in person or by phone. • Approximately 2,700 customers paid with on-line banking payments. Utility Billing also receives payments by mail and accepts payments at the walk-in customer service window located in the Municipal Building. In May 2009, Utility Billing implemented the Utility Billing Red Flag Identity Theft Prevention Policy in accordance with Federal Trade Commission regulations. Utility Billing now requires photo identification or other identification before changing the name on a utility account. Utility Billing also notifies owners by letter of any name changes on an account. The Utility Billing office complies with all City policies and the Peripheral Component Interconnect (PCI) security regulations when taking credit card payments. Although collections are an important financial function to the City, the City does not turn unpaid accounts over to a collection agency. Instead, the water service is turned-off and unpaid utility bills are certified annually to the county for inclusion on the property tax bills of the specific property. Throughout the year the City uses multiple techniques, such as courtesy reminder letters (60 days past due), final notice letters (90 days past due), 48 hour hang tags and payment agreements to avoid turn-offs and the certification process. In 2009, the City averaged 17 turn offs per month; 92 percent of final notices and hang tags generated payments before turn-off was necessary and Utility Billing only certified 16 unpaid balances to Boulder County for collection. As summarized in the 2000 TWMP from Smith, Phyllis. 1986. History of Water Works of Boulder, CO. 2 AWWA and WEF. 2008. QualServe Report of Peer Review for City of Boulder. October 3 Meschuk, 2010 4 City of Boulder_ 1981. Boulder Revised Code (B.R.C.)_ Available at: www.colocode_com/boulder2/index.htm 5BVCP City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-6 6 City of Boulder. 2003 with 2004 and 2009 revisions. Drought Plan Volumes 1 and 2. 7 Black and Veatch. 2007. BRWTF Integrated Source Water and Treatment Study 8 City of Boulder. 2000. Design and Construction Standards. Available: http://www.bouldercolorado.gov/index.php?option=com_content&task=view&id=209&Itemid=482 9 City of Boulder. 2000. Treated Water Master Plan 10 ISO Commercial Risk Services, Inc. 1995. Letter to Tim Honey, City Manager re: Public Fire Protection, Boulder, Colorado. June. 11 City of Boulder. 2000. Design and Construction Standards. November 92 City of Boulder. 2010. Utilities Annual Report. April 93 City of Boulder. 2010. Utilities Annual Report. April 94 Calculations of baseline water use documented in internal memo. Kosloff, MWH, April XX, 2010 15 Meeting notes, April 2, 2010 16 Calculations of current water use documented in internal memo. Kosloff, MWH, April XX, 2010 17 Production spreadsheet provided by Carol Ellinghouse on 4-3-2010, exception of year 2000, based on annual report data for that year. 18 City of Boulder. 2010. Utilities Annual Report. April 19 Production spreadsheet provided by Carol Ellinghouse on 4-3-2010, exception of year 2000, based on annual report data for that year. 20 Spreadsheet provided by Suzanne Givler on May 17, 2010 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page 6-7 momomm page (February2411) A-1 Utility of Boulder Final Draft Water Master Plan City Appendix A- Overall 1. Customer Service a) Evaluate causes of past customer complaints b) Develop program for system flushing c) Implement program for customer response to complaints d) Update web site with summarized customer survey results, water quality "frequently asked questions," water quality data, annual CCR e) Participate in QualServe (AWWA) Source Water 11. Deliver the highest quality water sources available for immediate delivery after allowing for needed storage reserves a) Use the highest quality water sources after giving consideration to the need to maintain sufficient reservoir levels for seasonal source changes, emergencies, and drought reserves b) Maximize use of direct flow water rights and direct exchange to the greatest extent possible to maintain reservoir reserves c) Maximize use of Boulder Creek exchange potential in order to increase the amount of Boulder Creek water available for delivery to Betasso WTF, increase hydropower production, and decrease water treatment and delivery costs while also increasing drought resiliency through use of available Boulder Reservoir supplies d) Maximize water deliveries to Betasso WTF in wet years when effects on carryover storage are minimal 12. Maintain sufficient reservoir drought reserves to achieve drought reliability criteriaa) Maintain carryover storage from wet years to dry years sufficient to meet drought reliability criteria by maintaining the minimum level reached for Silver Lake Watershed each spring above a twenty year running annual average of 6100 of and a minimum annual level reached in the spring for Barker Reservoir above a twenty year running average of 8500 acre-feet a) Operate Boulder Reservoir plant for a sufficient number of months each year to provide the necessary level of system drought resiliency 13. Maintain sufficient reservoir reserves to assure continuous water supply to Betasso WTF throughout the year and in emergencies a) Balance deliveries from each water source during the year to assure adequate usage of each and prevent excessive draw on upper Boulder Creek reservoirs b) Maintain minimum extreme drought reserve pool in Barker Reservoir of 2200 acre- feet, in the Silver Lake Watershed reservoirs of 1700 acre-feet and in Boulder Reservoir of 800 acre-feet for fail-safe ability to meet essential indoor needs in an extraordinary and unanticipated severe drought event City of Boulder Final Draft Water Utility Master Plan (February 2011) Page A-2 14. Maximize hydroelectric production a) Manage hydroelectric production to increase water utility revenues and generate "green" power without impacting source water reliability and quality a) Use Boulder Canyon Hydro storage right to store water for hydropower generation and strategic release to soften call at critical times b) Use Betasso discharge line to maximize capacity tests c) Use excess capacity in raw water transmission pipelines to run additional hydro water 15. Address instream flow needs a) Provide water for instream flow needs without significantly reducing municipal water system reliability b) Comply with CWCB agreements c) Continue voluntary instream flow releases at Barker Reservoird)Balance instream flow needs with municipal needs during drought by exercising drought reservation clause in CWCB agreements if neededSupport outdoor water use from the municipal system during periods when system demands can be wholly met through direct flow diversions, including use of larger customer water budgets in May and June, in order to increase water levels in the alluvial aquifer feeding Boulder Creek and other area creeks with instream flow support 16. Protect and enhance yield of city's water rights portfolio a) Participate in water court proceedings to establish new water rights for the city and to protect the yield of the city's existing water rights b) Pursue strategic water supply acquisitions that complement and enhance the city's existing water supplies and facilities to improve municipal water system operations or drought resiliency c) Maintain and improve the Boulder Creek Watershed model to enhance understanding of the city's source water supplies and operations d) Monitor climate change science developments and track climate and streamflow measurements to evaluate if local hydrology has shifted outside of the historic range of variability e) Complete water rights accounting sufficient to meet state requirements and to support city evaluation of water rights yields and uses over time i) Keep daily records of all diversions ii) Compile detailed summary reports monthly and annually 17. Maintain and protect source water system infrastructure and lands a) Continue existing ordinances and policies that protect source water system infrastructure and adopt new ones where needed b) Maintain closure of the Silver Lake Watershed c) Continue to improve security equipment and operations d) Maintain policies that prevent infestation of city reservoirs with nuisance species City of Boulder Final Draft Water Utility Master Plan (February 2011) Page A-3 18. Support local ditch company operations that complement the municipal system. a) Continue existing ordinances and policies that protect community ditch water supplies for local use by providing municipal protection against sales out of the Boulder Creek basin b) Advocate with water commissioner and others for use of ditch company water rights in a manner that supports yield of city water rights c) Support maintenance efforts for ditches that supply municipal infrastructure 19. Protect source water from point and non-point pollutants a) Operate a source water pollution prevention program b) Contain and secure treatment plant, water supplies, and intake structures from potential contamination per vulnerability assessment c) Consider human and domestic animal access to water supplies when considering land use access and changes d) Initiate water quality patrol position for Boulder Reservoir and Boulder Feeder Canal e) Implement Middle Boulder Creek Water Source Management Work Plan f) Develop and implement Boulder Reservoir Management Plan g) Coordinate with Parks on S. Shore Business Plan to include water quality protection measures h) Participate in point and non-point pollution regulatory development permits and source assessments i) Reduce potential water quality impacts from septic systems by promoting proper installation and management through the Boulder County Septic Smart Program and converting to existing collection system j) Reduce risk of emerging contaminants by reducing and controlling contamination from wastewater sources k) Implement best management practices where needed to protect water supplies from existing potential contamination 1) Enhance, protect, and maintain source water riparian and wetlands areas i) Establish conservation easements and riparian and wetlands buffer zones in source water areas ii) Maintain and improve stream channels and wetland features to reduce erosion and enhance treatment by natural systems iii) Develop outreach and education programs regarding the importance of riparian areas and soil and water conservation practices m) Monitor source water quality i) Continue source water monitoring and evaluation program to track water quality conditions ii) Continue to track unregulated contaminants to determine risk and evaluate monitoring need iii) Improve knowledge of emerging contaminant occurrence, prevention and treatment options City of Boulder Final Draft Water Utility Master Plan (February 2011) Page A-4 n) Adopt ordinances and policies protective of source water quality, such as a Watershed Ordinance to protect source water areas i) Designate source water protection areas to be regulated ii) Prohibit land use activity in designated source water areas which may creates risk of contamination or injury to the City's water supply or waterworks' iii) Restrict public access to protected watersheds and maintain closure of the Silver Lake Watershed to public access iv) Provide regulatory mechanism to enforce illegal discharges into source water areas v) Prohibit illegal discharges and regulate land-use activities in designated source water areas vi) Manage recreation uses to protect drinking water supplies vii) Establish watershed permitting system to regulate activities within the designated source water protection areas o) Adopt a city-wide source water anti-degradation policy2 i) Give preference to alternatives that maintain, protect, or enhance the quality of the water supply sources for decisions regarding resource use and resource development ii) Consider public water supply use as the highest priority when evaluating competing uses for the water sources 20. Encourage stewardship and regional cooperation, particularly with those entities affecting source waters and source water IandsEducate and coordinate with local governments and private landowners to manage and protect drinking water supplies a) Coordinate with local environmental groups to protect water supplies b) Coordinate with Boulder County on Boulder Feeder Canal recreational uses c) Investigate and cooperatively resolve pollution issuese) Coordinate with Northern Colorado Water Conservancy District on water system operations and improvements d) Work with Forest Service on Boulder Creek watershed management issues e) Pursue water conservation efforts that are tailored to Boulder's needs and do not impair yield of downstream water users, such as emphasizing wise indoor water use 21. Improve source water quality when possible through operational or other means a) Implement a manganese control strategy using source management techniques (e.g., in situ aeration) b) Coordinate with NCWCD to maximize flow through Boulder Reservoir c) Determine best source based on treatability, quality, and source water supply outlook The SWMP contains a link to a sample ordinance 2 An example is the American Water Works Association Statements of policy on public water supply matters retrieved January 15, 2009 from http://www.avvwa.org/files/about/OandC/Pol icyStatements/1209426115078. pdf City of Boulder Final Draft Water Utility Master Plan (February 2011) Page A-5 Water Treatment 22. Comply with all drinking water regulations and meet secondary standards a) Continue high quality treatment b) Evaluate DBP compliance forecast and establish DBP reduction plan, if needed. 23. Use best practices to maintain high quality treated water a) Jar test regularly b) Evaluate filter media on a regular basis c) Investigate problem filters when they become apparent 24. Seek alternative methods to increase delivered water quality a) Implement necessary upgrades to the Boulder Reservoir WTF to ensure a multi- barrier system. b) Improve clarification treatment. c) Implement procedures and reporting requirements to obtain Partnership for Safe Water - Phase I I I status. d) Implement the AWWA Standard for Water Treatment Plant Operations and Management (G200-09) e) Join Water Research Foundation (formerly AWWARF) f) Continued improvement of disinfection 25. Deliver similar and consistent finished water quality from both plants a) Set uniform levels for water quality parameters. b) Develop program to bring water from both plants into consistent range for measured parameters. c) Control pH and/or ORP of finished water. d) Minimize effect of mixing regions by implementing consistent multiple-plant finished water quality program 26. Ensure daily reliable plant operations at design flows a) Implement maintenance management program 27. Integrate public health risk factors into source water and treatment management decisions- a) Develop a Public Health Protection Index (PHPI) or Risk Index b) Establish Stakeholder group to assist in PHPI process c) Establish consensus of internal and external decision-makers on the PHPI applications. City of Boulder Final Draft Water Utility Master Plan (February 2011) Page A-6 28. Improve knowledge of emerging contaminant occurrence a) Perform the monitoring program included in the Unregulated Contaminant Monitoring Regulation. b) Continue to track unregulated contaminants to determine risk and evaluate monitoring need. Distribution System 29. Remain in the "below average" category for water main breaks for municipalities in the region a) Keep annual breaks below 120 b) Continue distribution system rehabilitee program and track performance 30. Design and operate distribution system with adequate storage to meet fluctuating customer demands and provide for emergency service a) A reserve capacity of 10 percent will be maintained in the water delivery system. The maintenance of such a reserve capacity will allow a degree of planning flexibility and mitigate water delivery problems that might be caused by operator error. b) Provide sufficient storage to meet daily demand fluctuations and fire flow protection 31. Maintain safe and consistent water quality throughout the distribution system a) Develop a monitoring program for the distribution system and a plan for adjusting water quality where necessary. b) Investigate Pb/Cu corrosion behavior and status. c) Maintain a minimum chlorine residual throughout the distribution system. d) Maintain minimal levels of bacteria in the distribution system e) Develop a plan to meet DBP criteria for reduced monitoring under Stage 1 DBPR and Stage 2 DBPR. f) Develop a plan to maintain water quality in distribution system reservoirs g) Implement and maintain effective backflow prevention program.3 h) Ensure integrity of all distribution system storage tanks. 3 Additional details of such a program are included in Black and Veatch (2007) City of Boulder Final Draft Water Utility Master Plan (February 2011) Page A-7 wWW.mwhgIobal. com 4 JkJ*A ~ r _ PREPARED FOR CITY OF BOUDER Treated Water Master Plan Update FEBRUARY 2011 " -VA poor, r Noon ~g _ ,fir- - Ilk Lih 0j, Uln e F i ve City of Boulder Treated Water Master Plan •Y~ "'~e~..~.- pia February 2011 FINAL DRAFT MWHO City of Boulder Final Draft Treated Water Master Plan (February 2011) Page i Table of Contents 1 Introduction ......................................................................................................................................1-1 1.1 Purpose ..................................................................................................................................1-1 1.2 Information Sources ---------------------------------------------------------------------------------------------------------------1-1 1.3 Report Organization ---------------------------------------------------------------------------------------------------------------1-2 1.4 List of Acronyms 1-2 2 Existing Facilities and Resources ..................................................................................................2-1 2.1 Raw Water Supply------------------------------------------------------------------------------------------------------------------2-1 2.1.1 Silver Lake Watershed 2-3 2.1.2 Barker Reservoir Watershed -------------------------------------------------------------------------------------2-3 2.1.3 Transmountain Diversion-------------------------------------------------------------------------------------------2-3 2.1.4 Water Resources Management 2-4 2.2 Water Treatment Facilities 2-4 2.2.1 Betasso Water Treatment Facility (BWTF) ................................................................2-4 2.2.2 Boulder Reservoir Water Treatment Facility (BRWTF) at 63rd Street .....................2-13 2.3 Treated Water Distribution System ......................................................................................2-22 2.3.1 Pressure Zones -------------------------------------------------------------------------------------------------------2-22 2.3.2 Treated Water Transmission ...................................................................................2-25 2.3.3 Treated Water Facilities ...........................................................................................2-26 2.3.4 Treated Water System Components .......................................................................2-32 2.4 System Control ---------------------------------------------------------------------------------------------------------------------2-33 2.5 Current Staffing 2-33 2.5.1 Staffing Summary----------------------------------------------------------------------------------------------------2-35 3 Water Quality Regulations and Goals ............................................................................................3-1 3.1 Water Quality Regulations 3-1 3.1.1 Historical Overview----------------------------------------------------------------------------------------------------3-1 3.1.2 Overview of Regulations ............................................................................................3-6 3.1.3 SDWA 1996 Amendments.. - - 3-6 3.1.4 Future Regulations ..................................................................................................3-17 3.1.5 State of Colorado Regulations ................................................................................3-24 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page ii 3.1.6 City of Boulder Regulatory Compliance Status 3-26 3.2 City of Boulder Water Quality Goals .....................................................................................3-36 3.2.1 Process Optimization .3-36 4 Treatment and Distribution Facilities Studies ...............................................................................4-1 4.1 City of Boulder Water Conservation Futures Study; 1999, Hydrosphere Resource Consultants, Inc ......................................................................................................................4-1 4.2 Treated Water Master Plan; 2000, Integra Engineering .........................................................4-2 4.3 2000 Treated Water Master Plan Recommendations and Implementation Plan Findings and Basis for Plan 4-3 4.4 Boulder Reservoir Water Treatment Plant Predesign Report (2003), Including an Evaluation of Mid-Term and Long-Term Improvements for the Facility .................................4-4 4.5 Boulder Reservoir Water Treatment Plant Source Water Quality Planning Study (Phase I Study) (2003) ------------------------------------4-5 4.6 City of Boulder Zone 1 Distribution System Analysis (2003) ..................................................4-6 4.7 Betasso Water Treatment Plant Facility Improvement Plan (2005) 4-7 4.8 Integrated Evaluation of the BRWTP Source Water Protection and Treatment Improvements Study (Integrated Study) (2007) .....................................................................4-8 4.9 AWWA Peer Review Report-, 2008 4-10 4.10 City of Boulder Water Conservation Plan (2009) 4-12 5 Facilities Evaluation .........................................................................................................................5-1 5.1 Water Treatment Plants 5-1 5.1.1 Betasso Water Treatment Facility 5-1 5.1.2 BRWTF at 63`d Street----------------------------------------------------------------------------------------------5-34 5.1.3 Regulatory Compliance ...........................................................................................5-47 5.2 Distribution System Facilities 5-60 5.2.1 Treated Water Transmission Pipelines ...................................................................5-60 5.2.2 Hydroelectric Generating Facilities ..........................................................................5-61 5.2.3 PRV Facilities ..........................................................................................................5-62 5.2.4 Pumping Facilities ---------------------------------------------------------------------------------------------------5-63 5.2.5 Treated Water Reservoir Storage ...........................................................................5-63 5.2.6 System Operation 5-68 5.2.7 Distribution System Maintenance Programs ...........................................................5-69 5.2.8 Hydraulic Evaluation ................................................................................................5-76 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page iii 6 Asset Management ..........................................................................................................................6-1 6.1 Previous Asset Management Studies ....................................................................................6-1 6.1.1 Betasso WTP Asset Management ............................................................................6-1 6.1.2 Iris and Cherryvale Pump Stations Asset Management ............................................6-2 6.2 Asset Management for BRWTF and Stranded Facilities ........................................................6-2 6.2.1 Boulder Reservoir Water Treatment Facility at 63rd St...... 6-3 6.2.2 Asset Management for Stranded Facilities 6-5 6.2.3 Overall Asset Management Results for the BRWTF and Stranded Facilities 6-9 6.3 Summary of Boulder's Overall Asset Management Strategy 6-10 7 TWMP Recommendations and Conclusions .................................................................................7-1 7.1 Treatment Facilities ----------------------------------------------------------------------------------------------------------------7-1 7.1.1 Betasso Water Treatment Facility 7-1 7.1.2 Boulder Reservoir Water Treatment Facility (BRWTF) at 63rd Street .......................7-3 7.2 Distribution System Recommendations .................................................................................7-6 7.2.1 GIS/UMMS Recommendations .................................................................................7-6 7.2.2 Hydroelectric Generating Facility Recommendations ...............................................7-6 7.2.3 PRV Station Recommendations ................................................................................7-7 7.2.4 Storage Reservoir Recommendations ......................................................................7-7 7.2.5 Distribution System Maintenance ..............................................................................7-9 7.2.6 Further Studies--------------------------------------------------------------------------------------------------------7-10 7.3 Asset Management Recommendations ...............................................................................7-10 7.4 Treated Water Improvement Project Recommendations 7-11 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page iv List of Tables Table 5-1: Betasso Water Treatment Facility Design Data ................................................................2-6 Table 5-2: Summary of Raw Water Hydroelectric Generation Facilities .........................................2-10 Table 5-3: Boulder Reservoir Water Treatment Facility Design Data 2-14 Table 5-4: Treated Water System Facilities Design Data ................................................................2-26 Table 5-5. City of Boulder Utilities Water Fund Staffing Levels 2-33 Table 5-6 Benchmark Comparison of Employee-Related Performance .........................................2-35 Table 5-7: Historical Regulations 1893 through 1996 3-2 Table 5-8: Stage 1 D/DBPRs .............................................................................................................3-9 Table 5-9: Required Removal of Total Organic Carbon ....................................................................3-9 Table 5-10: Routine Monitoring Requirements for Conventional Filtration Treatment Plants ...........3-10 Table 5-11: USEPA Bin Classification Table and Treatment Requirements for Filtered Public Water Systems under LT2ESWTR................................................................................. 3-15 Table 5-12: Contaminant Candidate List 3 (CCL3) ............................................................................3-18 Table 5-13: Categories of PPCPs Detected with Greatest Frequency in Unites States Geological Society (USGS) Urbanized Stream Reconnaissance Survey, (2002) Kolpin, et. al....... 3-19 Table 5-14: Comparison between Observed and Predicted No Effect Concentration for Some Common Pharmaceuticals ..............................................................................................3-21 Table 5-15: Notification and Response Levels for Nitrosamines in California ...................................3-23 Table 5-16: Disinfection Byproduct and Precursors - City of Boulder Water Quality Monitoring 3-26 Table 5-17: National Primary Drinking Water Regulations - Inorganic Chemicals ...........................3-29 Table 5-18: National Primary Drinking Water Regulations - Synthetic Organics ..............................3-31 Table 5-19: National Primary Drinking Water Regulations - Volatile Organic Chemicals .................3-33 Table 5-20: Secondary Standards 3-34 Table 5-21: Water Treatment Plant Overall Internal Operating Targets ............................................3-36 Table 5-22: Estimated Solids Production at BWTF ............................................................................5-24 Table 5-23: Estimated Surface Area Required, Based on Average Day Solids Production of 1,033 Dry Ibs/day 5-24 Table 5-24: Residuals Handling Improvements Alternatives .............................................................5-28 Table 5-25: BWTF Capacity Evaluation 5-29 Table 5-26: Analytical Results from BWTP Residuals 5-33 Table 5-27: Radiochemical Analysis Results from BWTP Residuals' ...............................................5-33 Table 5-28: Analytical Results from BRWTP Residuals 5-43 Table 5-27: Radiochemical Analysis Results from BWTP Residuals' ...............................................5-43 Table 5-30: BRWTF Capacity Evaluation ..........................................................................................5-45 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page v Table 5-31: Fire Flow Storage Requirements 5-67 Table 5-32: Recommended Fire Flow Storage by Pressure Zone ..5-67 Table 5-33: Storage Evaluation Summary - Future Demand Conditions (2035) ..............................5-68 Table 5-34 Technical Quality and Customer Service Complaints (per 1,000 Service Connections)-------------------------------------------------------------------------------------------------------------------5-74 Table 5-35: Distribution System Hydraulic Reliability Criteria 5-76 Table 5-36: Summary of Distribution System Piping .........................................................................5-78 Table 5-37: Pipe Material Distribution ................................................................................................5-79 Table 5-38: Comparison of Water Distribution System Integrity (Leaks/100 miles of Pipeline) ........5-79 Table 5-39: Consolidated Recommended Improvements Project List 7-13 List of Figures Figure 5-1: City of Boulder's Source Water System ...........................................................................2-2 Figure 5-2: BWTF Process Schematic------------------------------------------------------------------------------------------------2-5 Figure 5-3: Boulder Reservoir Water Treatment Facility Process Schematic 2-18 Figure 5-4: Water Distribution System Map ......................................................................................2-23 Figure 5-5: Water Distribution System Schematic ............................................................................2-24 Figure 5-6: BWTF Historical Flow Data - 2004-2009 5-2 Figure 5-7: BWTF Source Water Turbidity - 2004-2009 5-3 Figure 5-8: BWTF Source Water Color vs. Finished Color .................................................................5-4 Figure 5-9: BWTF Settled Water Turbidity - 2004-2009 5-6 Figure 5-10: BWTF High Flow Days 24 MGD) Settled Water Turbidity ............................................5-7 Figure 5-11: BWTF Barker High Turbidity Days 4 NTU) Settled and Raw Water Average Turbidity--------------------------------------------------------------------------------------------------------------5-8 Figure 5-12: BWTF Lakewood High Turbidity Days 4 NTU) Settled and Raw Water Average Turbidity-------------------------------------------------------------------------------------------------- -----------5-9 Figure 5-13: BWTF Source Water Color and Settled Turbidity ...........................................................5-10 Figure 5-14: BWTF Filters - Rate of Filtration vs. Average Filter Turbidity ........................................5-11 Figure 5-15: BWTF High Flow Cases 24 MGD) Average Filter Turbidity 5-12 Figure 5-16: BWTF Historical UFRV Data Trendlines Only - One Week Moving Averages ..............5-13 Figure 5-17: BWTF Historical UFRV Data - Filters 1-4 Only 5-16 Figure 5-18: BWTF Historical UFRV Data - Filters 5-8 Only ..............................................................5-17 Figure 5-19: BWTF Historical Source Water, Finished Water Color and UFRV .................................5-18 Figure 5-20: BWTF Site Plan Showing Location of Gravity Thickeners and Centrifuge Building 5-27 Figure 5-21: BWTF Residual Flow Streams ........................................................................................5-31 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page vi Figure 5-22: Existing Waste Impoundments at the BWTF 5-32 Figure 5-23: BRWTF Raw Water Turbidity 5-36 Figure 5-24: BRWTF Raw Water pH Probability - 2005-2009 ...........................................................5-36 Figure 5-25: BRWTF Raw Water Alkalinity Probability - 2005-2009 5-37 Figure 5-26: BRWTF DAF Effluent Turbidity Probability - 2005-2009 ................................................5-37 Figure 5-27: BRWTF Filter Effluent Turbidity. - - - 5-38 Figure 5-28: BRWTF Filter Effluent Turbidity Probability - 2005-2009 ...............................................5-39 Figure 5-29: BRWTF Residual Flow Streams .....................................................................................5-42 Figure 5-30: Existing Waste Impoundments at the Boulder Reservoir Water Treatment Facility 5-42 Figure 5-31: BWTF Settled Water Turbidity - 2004-2009 5-48 Figure 5-32: BWTF Settled Water Turbidity Probability Plot - 2005-2009 .........................................5-49 Figure 5-33: BWTF Filtered Water Turbidity - 2005-2009 5-49 Figure 5-34: BWTF Filtered Water Turbidity Probability Plot - 2005-2009.- ......................................5-49 Figure 5-35: BRWTF Settled Water Turbidity - 2005-2009 ................................................................5-50 Figure 5-36: BRWTF Settled Water Turbidity Probability Plot - 2005-2009 .......................................5-50 Figure 5-37: BRWTF Filter Turbidity - 2004-2009 ..............................................................................5-51 Figure 5-38: Boulder Reservoir WTF Filter Turbidity Probability Plot - 2005-2009 ............................5-51 Figure 5-39: BWTF Effluent Chlorine Residuals - 2004-2009 ............................................................5-52 Figure 5-40: BRWTF Effluent Chlorine Residuals - 2004-2009 .........................................................5-52 Figure 5-41: Boulder Distribution System TTHM for D/DBPR Compliance Points - Locational Running Annual Average ..............................................................................5-54 Figure 5-42: Boulder Distribution System HAAS for D/DBPR Compliance Points - Locational Running Annual Average 5-54 Figure 5-43: BWTF and BRWTF Effluent TTHM Concentrations .......................................................5-56 Figure 5-44: BWTF and BRWTF Effluent HAAS Concentrations 5-57 Figure 5-45: BWTF and BRWTF Finished Water pH - 2004-2009 .....................................................5-58 Figure 5-46: BWTF and BRWTF Finished Water Alkalinity - 2004-2009 ...........................................5-59 Figure 5-47: Prioritization for Pipeline Replacement Program 5-81 Figure 6-1: BRWTF 50-Year Renewal Forecast 6-3 Figure 6-2: BRWTF Renewal Forecast by Discipline ..........................................................................6-4 Figure 6-3: BRWTF Renewal Forecast by Facility ..............................................................................6-5 Figure 6-4: Hydroelectric and PRV Facilities 50-Year Renewal Forecast ..........................................6-6 Figure 6-5: Hydroelectric and PRV Facilities Renewal Forecast by Facility 6-7 Figure 6-6: Water Storage 50-Year Renewal Forecast .......................................................................6-8 Figure 6-7: Water Storage Renewal Forecast by Facility ...................................................................6-9 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page vii List of Appendices Appendix A: City of Boulder Treatment Operations Regulatory Requirements A-1 Appendix B: Additional Figures from Evaluations of Water Quality and Betasso Water Treatment Facility Performance B-1 Appendix C: Water Utility Master Plan Hydraulic Modeling Results C-1 Appendix D: City of Boulder Utilities Finished Water Energy Dissipation Stations Inspection Report------------------------------------------------------------------------------------------------------------- D-1 Appendix E: City of Boulder Utilities Finished Water Reservoirs Inspection Report E-1 Appendix F: Asset Management Update for BRWTF and Stranded Facilities .....................................F-1 1 Introduction 1.1 Purpose The Treated Water Master Plan (TWMP) is intended to be a comprehensive summary of the City of Boulder's (City's) treated water system, including the Betasso Water Treatment Facility (BWTF), the Boulder Reservoir Water Treatment Plant (BRWTF), and the associated treated water storage and distribution facilities. The purpose of this TWMP is to describe and document the City's treated water system, provide an evaluation of the current conditions, and offer recommendations for improvements. This TWMP and its recommendations provide a framework for the management of the City's treated water systems in order to ensure reliable and safe treated water supply for the citizens of Boulder_ 1.2 Information Sources Many references were used in the preparation of this TWMP. Specific sources are identified throughout the document; however, some of the previous reports are summarized below. • 2000-2010 City of Boulder Annual Reports • 1999, City of Boulder Water Conservation Futures Study, 1999, Hydrosphere Resource Consultants, Inc. • 2000 Treated Water Master Plan, Integra Engineering • 2003 Boulder Reservoir Water Treatment Plant Predesign Report, MWH • 2005 Betasso Water Treatment Facility - Facility Improvement Plan, Carollo • 2007 Integrated Evaluation of the BRWTF Source Water Protection and Treatment Improvements Study (Integrated Study), Black & Veatch • 2008 American Water Works Association (AWWA) Peer Review Report, QualServeTM • 2010 Source Water Master Plan, MWH In addition, this TWMP includes the information gained through several meetings with the City of Boulder staff, evaluations performed by MWH, and historical data provided by the City. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 1-1 1.3 Report Organization The TWMP consists of the following items and subsections: • Section 1 Introduction • Section 2 Description of the existing facilities and resources, including: > The raw water supply > Water treatment facilities > Treated water distribution system > System control > Current staffing • Section 3 Summary of historical and new water quality regulations and goals • Section 4 Review of historical treatment and distribution facilities reports and studies • Section 5 Evaluation of water treatment plant and distribution system facilities • Section 6 Asset management evaluation, including a summary of Betasso Water Treatment Facility and the Cherryvale/Iris pump stations, and an evaluation of the Boulder Reservoir Water Treatment Facility and the stranded facilities • Section 7 Recommendations, conclusions, and recommended studies, including: > Previous study recommendations > Treatment facilities > Distribution system 1.4 List of Acronyms The following list of Acronyms is provided for the benefit of the reader. AL Action Level AWWA American Water Works Association BFC Boulder Feeder Canal BVCP Boulder Valley Comprehensive Plan BWTF Betasso Water Treatment Facility BRWTF Boulder Reservoir Water Treatment Facility at 63ftl Street C-BT Colorado-Big Thompson CCL Contaminant Candidate List CCR Consumer Confidence Reports CDPHE Colorado Department of Public Health and Environment CIP Capital Improvement Program City City of Boulder CPE Comprehensive Performance Evaluation CT Concentration X Time CWSS Community Water Supply Study DAF Dissolved Air Flotation DBP Disinfection Byproducts D/DBPR Disinfection/Disinfection Byproducts Rule EDCs Endocrine Disrupting Compounds EDSP Endocrine Disruptor Screening Program City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 1-2 ESWTR Enhanced Surface Water Treatment Rule FBRR Filter Backwash Recycling Rule FTE Full Time Equivalents FY Fiscal Year GAC Granular Activated Carbon GAO General Accounting Office GIS Geographical Information System gph gallons per hour gpm gallons per minute GRW Groundwater Rule HAAS five Haloacetic acids HDPE High Density Polyethylene Pipe HMWMD Hazardous Materials and Waste Management Division Hp Horsepower ICR Information Collection Rule USE Initial Distribution System Evaluation I&C Instrumentation and Control IESWTR Interim Enhanced Surface Water Treatment Rule IOCs Inorganic Chemicals kW Kilowatts LCR Lead and Copper Rule LRAA Locational Running Annual Averages MCLs Maximum Contaminant Levels MCLG Maximum Contaminant Level Goal MG Million Gallons MGD Million Gallons per Day mg/L Milligrams per liter MDD Maximum Day Demand MO Motor Operated MOA Memorandum of Agreement MRDLs Maximum residual disinfectant levels MRDLGs Maximum residual disinfectant level goals NCOD National Contaminant Occurrence Database NOM Naturally occurring organic matter NPDWRs National Primary Drinking Water Regulations NSDWRs National Secondary Drinking Water Regulations PAC Powdered Activated Carbon PLC Programmable Logic Controller PRVs Pressure reducing valves PSOCs Potential sources of contamination PWS Public Water System NTU Nephelometric turbidity units O&M Operations and Maintenance psi Pounds per square inch rpm Revolutions per minute SCADA Supervisory Control and Data Acquisition SDWA Safe Drinking Water Act SOCs Synthetic organic chemicals SOPs System operating principles SRF State Revolving Fund SWAA Source Water Assessment Area SWAP Source Water Assessment and Protection Program SWMP Source Water Management Plan SWPA Source Water Protection Area SWTR Surface Water Treatment Rule TCLP Toxicity Characteristic Leaching Procedure City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 1-3 TCR Total Coliform Rule TCRDSAC Total Coliform Rule/Distribution System Advisory Committee TDH Total dynamic head TENORMs Technologically Enhanced Natural Occurring Radioactive Materials TOC Total organic carbon TTHM Total trihalomethane TWMP Treated Water Master Plan UCMR Unregulated Contaminant Monitoring Regulation UDF Unidirectional Flushing Program UFRV Unit filter run volume UMMS Utilities Maintenance Management System USEPA United States Environmental Protection Agency USPHA United States Public Health Service VOCs Volatile organic compounds WTF Water Treatment Facility WTP Water Treatment Plant WTRs Water treatment residuals/sludge WQCC Water Quality Control Commission WQCD Water Quality Control Division WQES Water Quality and Environmental Services WWTP Wastewater Treatment Plant City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 1-4 2 Existing Facilities and Resources Effective planning begins with an up to date description of the existing facilities that make up the treated water system. The City of Boulder's water system consists of raw water collection, storage, and conveyance facilities, hydropower facilities, two treatment plants, and treated water transmission, storage and distribution facilities. This section provides an overview of the system including: • a brief summary of the source water system, • a description of the BWTF, • a description of the BRWTF, and • a description of the treated water distribution system. 2.1 Raw Water Supply The City of Boulder derives its water supply from two surface water sources, the upper watershed of Boulder Creek and the upper Colorado River basin via the Colorado-Big Thompson (C-BT) Project transmountain diversion. The Boulder Creek sources are further subdivided into the City-owned Silver Lake Watershed on North Boulder Creek and the Barker Reservoir watershed on Middle Boulder Creek. The Colorado River transmountain diversion supply includes units of the C-BT system which is owned by the Bureau of Reclamation and operated by the Northern Water (formerly Northern Water Conservancy District) and units of the more recent Windy Gap Project which is owned and operated by the municipal subdistrict of Northern Water. Figure 5-1 shows the City's source water facilities. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-1 Figure 5.1: City of Boulder's Source Water System Color Code C Untreated Water Storage Reservoirs cc) / J CITY OF BOULDER SOURCE WATER FACILITIES ■ Raw WaterTransmission Facilities and Diversion Structures ! ■ Op 1300 WaterTreatment Facilities ■ Raw Water Hydroelectric Facilities i - . 1{ a - .fit a?' .t. (~`S~' 1 ~y' !1~ - - .+.i~. ~ ~~~r,, - 1 ~ .ti L~xti'y.ti "'.~~5}i}~~'. r~'~jW ~~r\*~ r •,i J. Y . 7 - _ L. ~~R•~ . _ R1nvr`°"' ltdGm Cmk ; . T , ~`ap 'i ~ _ . * . /Lri _ y(~ .r~`• r IRr.imoir 9-kwek (xjt- r ~y M 6ranCY Gho laFe`b +?Z M ~f./Iil~~ ra- LnMhr rL'',r' ;r• `,y~ fa'!.`~ 7 t j t'` >•f11'i° •~ir ^ .~dscraper. Reservo i°r A~ z N e x FraaerMlmlorParts 'f tr, r' 4, , Mir " and a. E&tesPak t c• t ±All~~or LalrNland Gruen sakes Nos. IT V r Ire Pipeline,and'Diversion fi..•~"f j ae r. sr, rid(Goose Lakes i4- -kill [Die e, L2lcewoncl;Reservoir, North;Roulcler Creek, f ` ti'j _ : t r~ J Park Reservoir Site Nam l a r L' ► f and Como Creek Diversion`+ ~~S r ,`+Cari6oiRanch-} :d~/! '~F p it ♦ / Y i _j+ p +F I~~ % ,t ,l' ••S Tye' lte H dr0 r rQ j~ r i .~~a . ` 1~"' i i' i , 1 Silver La { edLdao{ Rm ar rr. , - S i `y , r~ -r'•~y • + - 1 t / 4 .Ba~l<e'rReservoir - t ! n? stow Boulder Canyon r ~r 4 . L 1v, y~ Gravity Line N . ; +g.v. kh.7~, ` 'f' ~t. ~1 4 y ; j .1'• RrJr,irh, ( 1 1 _9 07 + ~I eline ~frf1YJ f w' wee ' ji`~~±rr e .a.. / r r s F ~J f ~ P"' .l 1 'I r , 1~ " ~ a _a. fr~+~, ~ l' C•~k _.~r J c ~g~,tl,rl , omHy,dro Penstock E / Penstock~'~) 1p r 3 V - f f S , 3-G'r °r ,►,};s~. ft J. Lys . ~s + 4 -,A ii *,r. „ f_ Betasso,Water- reatment!Facility .,,Kossler Reservoir/,e~ait 'wd . ✓ •.jrR ,t- ± \ lyr . Y ~1 + j / Lr l ~ lr f r ~ ~~{d ~ , • iF~ H 1+~1!' LakeVdood'ro d BL: o ta,d ' oBoulder CanyonrHydro y d a n _1 `j Oradell-Hydro Boulder' Boulder Feeder Canal-~ ~v _ \ I E!.Ir~~- - a 4®OUmH ~IeseNOir WTF Boulder Reservoir Boulder ReservoirWaterTrea~t Facility ~ 1 ' . r ~ ` Y. Lngmont ~ Baseline Reservoir I ~ J( Wlttemyer,PondS yeast of the inte_r,eo n.ffHHwy Ei2 nddCCounty L'i r Roac'„ City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-2 Ownership of the 10 square mile Silver Lake Watershed was granted to the City by a series of Congressional acts between 1907 and 1927. Source water derived primarily from snowmelt is stored in seven reservoirs and released as required. Silver Lake is the last reservoir in the series of Silver Lake Watershed reservoirs. Raw water released from Silver Lake is diverted from North Boulder Creek into the Silver Lake Pipeline about two miles below the reservoir. The original Silver Lake Pipeline, built in 1919, was replaced during 1997 and 1998 to improve system reliability. A new hydroelectric generating facility was constructed along with the new pipeline- The Silver Lake Pipeline terminates at Lakewood Reservoir, a small impoundment located a short distance north of Nederland, used for flow equalization. At Lakewood Reservoir both North Boulder and Como Creeks can be diverted into the reservoir. The watershed tributary to Lakewood Reservoir includes the Silver Lake Watershed and encompasses a total of 31 square miles. From Lakewood Reservoir water is conveyed approximately 9.5 miles to the BWTF via the Lakewood Pipeline. This pipeline was originally constructed in 1906 and was rebuilt in the 1940s and 1950s. Replacement of the lower 1.1 miles of the pipeline was completed in 1995 but the remainder was in poor condition, vulnerable to breaks and unable to operate at its full hydraulic capacity, which significantly reduces system reliability and operational flexibility. In addition, substantial portions of the pipeline operated as a non pressure pipeline resulting in the entrainment of large amounts of air in the raw water. The release of this entrained air during treatment at the BWTF adversely affected the plant's performance. The City pursued environmental approvals for replacement of the Lakewood Pipeline from the late 1980s through the early 2000s. Starting in 1995 and completed by 2003, the entire stretch of Lakewood Pipeline was replaced. The new pipeline is a high pressure line throughout its length, which has dramatically reduced air entrainment and enhanced system reliability and hydraulic capacity. Barker Reservoir was constructed in 1909 by the predecessor of Public Service Company of Colorado (prior to Xcel Energy). Raw water is piped from Barker Reservoir to Kossler Reservoir and from Kossler to the Boulder hydroelectric power plant. The City of Boulder has used the Barker Reservoir/Middle Boulder Creek water since 1954. In 2001, the City purchased the Barker system. The Barker System includes of Barker Dam, the hydroelectric generating plant and the conveyance pipelines to the hydroelectric plant. Purchase of these facilities facilitated pipeline improvements increasing reliability and enhancing system operating flexibility. Water is collected in a series of reservoirs located in the upper Colorado River watershed and diverted to the eastern slope of Colorado via the C-BT transmountain diversion project- Water conveyed to the eastern slope through the C-BT system mixes with water from the upper Big Thompson River watershed in Lake Estes. From Lake Estes, water is directed to a number of Front Range storage reservoirs, including Carter Lake, for distribution to users by Northern Water. Boulder's share of this water is conveyed by the open channel Boulder Feeder Canal (BFC) from Carter Lake to Boulder Reservoir. The City owns units in both the original C-BT project and the Windy Gap project entitling it to a certain amount of water annually. Each Windy Gap unit has a potential yield of 100 acre feet of water annually. Each C- BT unit has a maximum yield of one acre-foot per year with an average yield of 0.7 acre-feet. The quota per unit is set each year by the Northern Water, and varies from year to year depending on the previous year's precipitation and water use. The City sells its unused water to agricultural users. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-3 The City has investigated options for a pipeline that would connect Carter Lake directly to the BRWTF eliminating the use of the BFC for raw water transmission. This would improve the source water quality to BRWTF and also allow full-time use of the better quality, Carter Lake water. Currently the BFC only operates during the summer months, primarily for irrigation. The City's raw water resources are managed by the Water Resources Group. This group is responsible for collection, storage and delivery of raw water supplies to the City's water treatment facilities. In addition to operating and maintaining the City's raw water storage reservoirs and raw water pipelines and canals, the Water Resources Group maintains the water rights accounting for raw water used by the City and negotiates sales, acquisitions and transfers of water between the City and other users. The Water Resources Group determines the amounts of water to be diverted from each source at any given time for optimal use of the City's water resources based on a complex combination of interrelated factors including water rights priorities, storage levels, snow pack projections, treatment costs, and water quality. These determinations are used to set the operating rates and source water mix at each of the City's water treatment plants. 2.2 Water Treatment Facilities The BWTF, located west of the city near Sugarloaf Mountain, was originally constructed in 1964. It was expanded to its present capacity in 1976. At about the time of the expansion, 50 MGD became widely accepted as the design capacity of the BWTF. Over the years, numerous minor improvements have been made to the plant and a major upgrade to the chemical systems was completed in 1996. At present, another major upgrade is planned that will improve the solids handling systems and enhance filter performance. The existing plant is depicted schematically on Figure 5-2. Treatment consists of coagulation, flocculation, sedimentation, filtration, and disinfection. Polyaluminum chloride and alum are used as coagulants. Facilities to feed powdered activated carbon for taste and odor control are available, but not used. Except for the polymer, which is a component of the polyaluminum chloride compound, no polymer is used at present for coagulation/flocculation. The plant has four covered double-deck flocculation/settling basins, with horizontal paddle wheel flocculators and solids collection equipment on the lower level. Solids are discharged to sludge drying beds where they are dried prior to offsite disposal by land application. The filtrate and decant from the drying beds drains by gravity to the sludge filtrate equalization tank and is pumped to the spent backwash equalization (SBE) basin of the recycle pretreatment facility. There are eight constant-rate, mixed-media (anthracite, sand, and garnet) filter units. Filtered water is dosed with fluoride and disinfected by chlorination. Lime and carbon dioxide are added for corrosion control prior to discharge to dual clearwells. Surface washing capability is provided and the filter media is supported by Leopold underdrains. Filter backwash is discharged into the SBE basin. From the SBE basin, the filter backwash water is pumped to the dissolved air floatation (DAF) process where it is thickened. Subnatent is returned to the head of the plant and mixed with raw water for treatment. Thickened residuals are sent to the lagoons. Filter backwash can also be discharged to the filter to waste tank and then pumped back to the head of the plant. The following paragraphs describe the BWTF process facilities in greater detail. An inventory of the major components of the BWTF is provided in Table 5-1. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-4 Figure 5.2; BWTF Process Schematic NOTES: Rod dots denote flaw maasurernent City of ESaulder,s Betasso Water Treatment Facility PWSID', CO.0107152 Pink Airows denote Sampling Points Facility 001 Process Schematic NP1)ES Discharge Perrnit # COG - OCA0064 - Point ODD was e~lmir,ate d in 2004- paint 004 was eliminated in 2r)D7 40 MG D Capacity Nbt to Scale - revised 02-10 VLJ C02 was chang.~i to Carbonic aeld {CI-12D3) to 2007 LakowaodIntake _ _ -P.esrluels Filtrate - - - - - _ - - _ ; Overflow vOverflow ICY Middle 8Cr skier Creek~ I,. i FL I f slduals Filtrate DIs 6,targe B Recovery Tank I 9 NPI3ES DIsdiar. ffpl~:Osl L--------Pe~rtit D02 r7t 6D3 1 -IP Lagoons r4- ' Pump Residuals _ aprkYna; House i- - - - - - - - - arn~v l 139T Drying Bed L Polymer ' I I 1 F- A CI2, F- 1 Spmii Backwash + 1MDG Recycle Water Pry 1 T Line 00 Residuals 1 ' ! Equalization treatment - Flocculation? Diml-rod ! GlearwHll dlSkrlM uti rt ' Alt Fl6aWlon DAF1 ' Drying Bed l CW002 System Polymer ► Alum l ROSIC LAIl, Preyed P,4Cl i ~ 30'Line ' Clilclr~e Sumaclear 1 _y_ _ 417 - _ BD01 CH20~ 1 2,5 MG Carl~r~ I ~ +ulesrwEU 1 ' Four Flocculation Sedimentaition Basins (1.5 MG ea) Rapltl i I CW001 l~. Backwash" Mlk I 4 3 2 1 Past-Sed Com~i r ed Raw Chlorine Sour" SSW1 L- I 1 14111 1, Filer 1 i r-------r---'---T------t--- ash ~ ; r ~~~udsr Lima 5ur9e ' Optional' Post-Filler Bhamber _ # 1 Chlorine BC06 S 7 6 5 4 3 r2l ' Filter l~ Y F lunride waste CFE001 Eight Mixed Media Filters (57,p00 goal each - CH3 reclavery rated at 4 94mintsq ft) TCtG al. Option F;l~rt9te------------------- Lakewood Eetasso Aerator GacG(ato i v..,..,......-. [~Viaklv1+e ~t ptivnai QiUS"inter SHr~aralor fw.& in 20CM Urker Intake ' Filler Building and Hydro Flur9w dFains q4 tea 01iliWalw SVdDO3 Separator wtYirh is pumped to the drying beds City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-5 Table 5-1: Betasso Water Treatment Facilitv D9sinn Data Item Design Data Notes Design Flow 50 (million gallons per day) MGD Raw Water Supply: Although the design flow for the BWTF is 50 24-inches, 20 MGD MGD, the actual capacity is likely 40 MGD or Lakewood Pipeline (short term emergency conditions up less. In addition, seasonal variations in water to 30 MGD) quality, flow splitting, pretreatment performance 27.7 MGD and process equipment conditions limit the Barker Pipeline (short term emergency conditions up capacity to approximately 25 MGD under spring to 40 MGD, longer term emergency run-off conditions. conditions up to 30.1 MGD) Pressure Reduction Barker Pipeline VAG PRV Controlled through the Betasso hydro generation facility or the new VAG valve Lakewood Pipeline 24-inch Mokveld PRV Controlled through the Lakewood hydro generation facility or the Mockveld valve Influent Flow Measurement Barker Vault The Parshall flume is located in the lime room Type Differential pressure under the steel walk plates. There is an Lakewood Vault ultrasonic level indicator that is located on a Type Differential pressure stilling well in the lime room. This stilling well is Combined connected by a 2" diameter line to the flat portion Type Parshall flume of the flume from the bottom. This 2" line and Size 5 feet stilling well can be located from the filter gallery basement. The ultra-sonic level indicator on this stilling well measures the water level and the flow into the plant and then SCADA calculates flow from this level. There is a 2" hypochlorite line that runs perpendicular to the flow of the Level Measurement Ultrasonic level sensor water downstream from the stilling well 2" line. This line is within the flow of water and could be compromising the accuracy of the ultra-sonic flow indication. This line is slated to be moved to above the maximum water level of the flume in the winter of 2010 for this reason. Rapid Mix Type Pumped Diffusion Flow 800 gpm Installed in 2006, but reportedly does not Pump Type Horizontal Centrifugal function as designed. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-6 Item Design Data Notes Flocculation/Sedimentation Number of Basins 4 Type Rectangular over/under Dimensions: Flocculation Zone 79.5' x 36.5' x 10' Sedimentation Zone 85' x 71' x 11' lower level plus 85' x 107' x 8' upper level Flocculators Horizontal paddle, 6' diameter Stages 3 Sludge Collector Chain and flight Detention Time Flocculation - 25 minutes Sedimentation - 2 hours Filtration Number 8 New media in 1995, recapped with anthracite Type Mixed - anthracite/sand 1998, recapped #4-8 with anthracite again in Surface Area, each 1,056 ft2 2009. Loading Rate @ 50 MGD 4.7 gpm/ft2 Loading rate value is with one unit offline. An old level sensor that utilizes compressed air to read the still-well level of the basins is located in the lime room. This level sensor is the master Filter level control Compressed air level sensor filter level control and provides feedback to the filters and tells them whether to increase or decrease flows to keep the basins and filters at the correct level. This instrument is on a still-well that is connected to the 36" filter flume header. Backwash Backwash Rate 5 to 15 gpm/ft2 Low rates (5-7 gpm), high rates (13-17 gpm) Wash Water Pumps Number 2 1-5 hp emergency backup pump Capacity, each 972 gpm Wash Water Supply Tank Type Welded steel Diameter 32.5 feet Water Depth 32 feet Capacity 200,000 gallons Spent Backwash Equalization (SBE) Basin Type Concrete walls, asphalt-concrete floor Dimensions 41 ft wide x 121 ft long x 18 ft high Clari-Vac® sludge removal Water Depth 13 ft (height of overflow weir) Capacity 700,000 gallons City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-7 Item Design Data Notes Dissolved Air Floatation (DAF) DAF Thickener Type Nordic Water Products Polymer can be added to aid in thickening SBE sludge. Capacity 1 MGD Chemical Systems Alum Liquid Storage Tanks Two at 12,700 gallons each Feed Pumps Two at 66.12 gph Average Dosage 10-12 mg/L Polyaluminum Chloride Liquid Type Sumaclear® 820B Storage Tanks Four at 1165 gallons Four at 900 gallons Feed Pumps Two at 69.66 gph Average Dosage 5-7 mg/L Powered Activated Carbon Slurry Bulk Storage Tank 48,800 gal Feed pumps One at 69.66 gph Dose 5-7 mg/L Lime Storage Hoppers 2 Capacity, each 25 tons Feeders Number 1, 1 Type 1 Volumetric screw, 1 Metered Pump Rate 3,800 lb/day Average Dose 25 mg/L Fluoride Liquid Hydrofluorosilicic acid Storage Tank One at 8,450 gallons Feed Pump Number 1 Type Pulsa Range One at 12.73 gph Average Dose 0.9 mg/L Carbon Dioxide Gas Type Tomco® feed system Disinfection Type Sodium hypochlorite 10% solution Storage 5 tanks at 4,000 gallons, each Average Dose: Pre 1.5 mg/L Post 1.3 mg/L City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-8 Item Design Data Notes Clearwell Number 2 Type Welded steel Capacity: Tank 1 2.5 MG Tank 2 1.7 MG Overflow Elevation 6,378 Water Depth 34 feet Treated Water Transmission Flow Measurement Venturi Tubes Sunshine Canyon Pipeline 30-inch, 50 MGD Boulder Canyon Pipeline 24-inch, 10 MGD Solids Handling South Lagoons Number 2 Length 200 feet each; 400 feet total Width 50 feet Surface Area 10,000 f12 each; 20,000 f12 total Side Water Depth 5.1 feet Freeboard 1.5 feet Working Depth 3.6 feet Working Volume 269,500 gallons each, 539,000 gallons total North Lagoons Number 2 Length 143 feet Width 48 feet Surface Area 7,000 f12 each; 14,000 ft2 total Depth 4 feet Volume 208,000 gallons each; 416,000 gallons total Residuals Drying Bed Type Concrete Pad Length 120 ft Width 75 ft City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-9 2.2.1.1 Hydroelectric Generation Four hydroelectric generation facilities are currently in service that generates power from the raw water feeding BWTF. Table 5-2 provides a summary of these facilities- T aw Water Hydroelectric Generation Facilities Hydro Name Placed into Service Capacity in kW 2009 Annual kWh 2006 Annual Revenue Betasso/Lakewood Hydro 1987 6,400 16 Million $922,969 Silverlake Hydro 1999 3,200 10.7 Million $596,328 Boulder Hydro 2001 10,000 11.8 Million $286,788 Total 19,600 38.5 Million $1,806,085 2.2.1.2 Pressure Reduction Pressure reduction on the Barker Pipeline is controlled through the hydroelectric facility or by a Howell- Bunger pressure reducing valve (PRV). Pressure in the Lakewood Pipeline is reduced by a Mockveld PRV on site. A strainer is installed ahead of the PRV to keep larger material out of the PRV. The Mockveld PRV reduces the incoming pressure from about 300 pounds-per-square-inch (psi) to approximately 10 psi. A rupture disk designed to fail at 50 psi is installed in a branch line on the downstream side of the PRV. This safety system discharges to a natural drainage downhill from the PRV station. The Lakewood Pipeline also has a hydroelectric turbine/generator that is used for pressure reduction. 2.2.1.3 Raw Water Blending Raw water from the Silver Lake/Lakewood Reservoir and Barker Reservoir sources is metered and blended together in a yard vault a short distance south of the plant. The vault also houses valves for controlling the total amount of flow and the relative proportions of water from each source. 2.2.1.4 Flocculation/Sedimentation The plant has four flocculation/sedimentation basins. Two were constructed as part of the original plant in 1963 and the other two were added when the plant was expanded in 1975. Basins are two-level with flocculation and sedimentation on the lower level and sedimentation on the upper level. Water enters the basin at the west end of the lower level and passes through three stages of flocculation aided by horizontal paddle wheels. The flocculation zone has baffles hanging from the ceiling between flocculators and it appears that this arrangement allows the flow to pass through the flocculation zone by a direct path that does not promote optimal flocculation- After flocculation the water passes into sedimentation. On the lower level of the basin settled sludge is moved by a chain-and-flight collector to a trough at the east end of the basin where it is conveyed by an auger to a draw off pit where a manually actuated mud valve allows for periodic draw off to the sludge drying beds. Process flow rises along the east end of the basin to the upper level. Vertical baffles made from redwood boards staggered to provide baffled slots are provided to distribute flow at the upstream and downstream ends of the upper level. Basins 1 and 2 have the original mechanical variable speed controls to vary the flocculator drive speed. These are old and worn and are hard to adjust making it difficult to fine-tune the flocculator speed. Basins 3 and 4 have been retrofitted with electronic variable speed units, which are very easy to adjust to facilitate optimization of process operation. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-10 2.2.9.5 Filtration There are eight filters, four built with the original plant in 1964 and four built when the plant was expanded in 1976. Filters are mixed media with simple perforated tile underdrains manufactured by Leopold. The mixed filter media contains anthracite, quartz sand, and garnet. The filter media was replaced in 1995 and was recapped with anthracite in1998 due to media loss (this media loss was likely the result of buoyancy caused by entrained air that has now been fixed). The filters were again recapped in 2009. Filters are operated on a constant rate basis with backwashing manually initiated on a run time basis. The old loss-of-head meters are in place, but ultrasonic level sensors are used instead. A flow meter and a rate of flow control valve are installed on each filter effluent line to control flow. Turbidity meters installed on each filter effluent provide one of the essential parameters used in operating the plant. Particle counters were installed in the mid-2000's on each filter and the combined filter effluent. Backwashing is accomplished by gravity flow from the backwash reservoir. Finished water is pumped from the plant clearwells to the backwash reservoir to provide sufficient hydraulic head for the backwashing process. Backwash flow is controlled by a flow meter and rate control valve in the line from the backwash reservoir. A surface wash system is provided to enhance cleaning of media during backwashing. The filters at BWTF also have filter to waste capability. 2.2.1.6 Chemical Addition Chemical systems include facilities for the addition of the following chemicals: • Alum > Primary coagulant. > Stored and fed as liquid. > Fed in the influent line with a chemical application stinger > Fed alone at times or fed along with PACT, see below. • Chlorine > Fed at a single location prior to sedimentation or at the effluent of each of the four flocculation/sedimentation basins, manual flow control. > Fed after filtration for disinfection and to maintain a residual out into the distribution system, PLC controlled flow pacing, and no residual trim. > Used a gas chlorine system until early 2000 when the process was converted to aqueous chlorine, (sodium hypochlorite, NaOCI, "bleach") primarily for public and employee safety. • Polyaluminum Chloride > Prior to 1998 meeting the then current filtered water turbidity limit of 1 NTU 95 percent of the time was often difficult particularly during the spring runoff season when raw water alkalinity and pH are lower than normal and TOC concentrations become elevated. These conditions combine to reduce the effectiveness of alum coagulation. To address this problem, the existing alum storage tank and feed equipment was adapted to the use of Polyaluminum chloride (PACT) (Sumaclearo) as a coagulant aid. In 2006, the existing storage tanks and feed pumps were relocated and two new tanks were installed. Alum and PACI are fed together at the head of the influent channel flume. > The addition of PACI made a significant difference in performance resulting in current average filtered water turbidities of 0.024 NTU (average of last 3 years). However, plant staff is still studying alternative application points and optimal combinations and locations of alum/PACT feed points to optimize the process to reliably meet the regulatory requirements. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-11 • Powdered Activated Carbon (PAC) > A system is available for delivery of powdered activated carbon. This system mixes the powdered activated carbon with water to create and store slurry, as well as feeds the slurry to the raw water influent flume to control taste and odor. This system was rehabilitated and upgraded as part of the 1996 plant improvements and is only occasionally utilized > In 2010 PAC was also used to treat the filter backwash water. • Polymer > The plant does not currently have a flocculant aid polymer system. > Polymer is used for plant recycle pretreatment and sludge thickening • Fluoride > Fluoride is added to the water after filtration. > Liquid hydorfluorosilicic acid is stored in a single tank. > Added to the flow in the finished water flume. • Lime > Lime slurry is fed into the finished water flume to increase alkalinity. > Hydrated lime is stored in two silos installed in 1996 as part of the plant upgrade. Silos have bin activators and air fluff systems to improve the lime feed. > Lime blenders installed in 1996 did not work well and were redone in 1997. Among other modifications, the concentration of the lime slurry was increased from 3% to 20% resulting in overall better performance with less scaling in the hoses. Even with these modifications, maintenance is still high. • Carbonic Acid > Fed to the raw water through a diffuser upstream of the rapid mixer. > Fed to the finished water through a diffuser in the final filtered effluent pipe upstream of the clearwells to adjust final pH for corrosion control, PLC controlled pH trim. > 50 ton storage cylinder located in yard just south of main plant building. • Chemical systems can be monitored through the SCADA system but many are manually operated except as noted above. With respect to the manually controlled chemical feed systems, chemical feed rates are manually calculated to match flow depending on solution strength and process requirements and metering pumps are manually adjusted to attain the desired feed rate. • Chemical Mixing > Mixing of treatment chemicals with influent flow utilizes a mechanical pumped diffusion flash- mixer which was installed in 2006. Installation of the system reportedly did not improve treatment. The system is sized to provide mixing at a plant flow of 46 MGD and should be more than adequate for current flows of 20 to 30 MGD. The rapid mix system is limited in its effectiveness. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-12 2.2.9.7 Residuals The residuals drying lagoons collect sludge from the sedimentation basins, the SBE basin, and the DAF thickener. Decant from the residuals drying lagoons is sent to the residuals filtrate recovery tank and then on to the SBE basin that discharges to the DAF. Waste filter backwash water is conveyed to the spent backwash equalization tank and then on to the DAF. Filter to waste flows are conveyed to the filter to waste recovery tank and then returned to the main flow stream just upstream of the rapid mixer. The concrete pad is used for drying and storing the dried residuals. Polymer is used for both plant recycle water and sludge thickening. The DAF and variable speed pumping system were installed in 2000 to improve the quality of the backwash water returned from the basin to the head of the plant and deliver it steadily to eliminate "slug" loading on the plant process created by the existing backwash water return system. A 700,000-gallon equalization basin to hold filter backwash water and sludge lagoon decant was also constructed at this time. Modifications were made to the filter effluent piping to convert the old backwash water holding tank to a filter-to-waste holding tank. In 2006 the existing sludge drying beds were demolished and new deep bed sludge dewatering lagoons were constructed. The City also experimented with modifications to the north lagoons to replicate sand drying bed functionality, but these modifications proved to be problematic due to the clogging of the sand and afforded no improvement to the residuals handling process. The BRWTF was originally constructed in 1971 to provide additional water treatment capacity during summer peak flow periods and to treat water from the City's C-BT/Windy Gap source. The plant is normally operated in the range of 3.5-8.5 MGD but is commonly run at up to 12 MGD during peak demand periods. A process schematic for the existing facility is shown on Figure 5-3. The BRWTF generally operates during the peak demand months and can be shut down for the remainder of the year. Several factors dictate the use of the BRWTF, including the relatively high cost of treating water at the BRWTF as compared with BWTF, best use of water resources, and periodic shutdowns at the BWTF or portions of the distribution system. When factors such as the costs of the raw water and raw and treated water pumping are considered, the cost of treated water from the BRWTF is approximately twice the cost of treated water from BWTF. The following paragraphs describe the BRWTF process facilities in greater detail. An inventory of the major components of the plant is provided in Table 5-3. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-13 Table 5-3: Boulder Reservoir Water Treatment Facility Design Data Item Design Data Notes Design Flow Rate 16 MGD (avg.)/20 MGD (peak) Raw Water Supply Boulder Feeder Canal 30 MGD Storage Boulder Reservoir 12,800 acre ft Raw Water Pumps Type Vertical turbine Number 3 1 Capacity 5,600 gpm 2,800 gpm TDH 27 feet 27 feet Rated hp 60 30 Influent Piping Flow Measurement Type Magnetic Flow Meter Operating Range 0-25 MGD Flash Mixer Type Pumped Diffusion Flash-Mixer Static Mixer Size 42 inches Flocculation/Clarification Flocculation Basins Number 3 Type 3-Stage Rectangular/Serpentine Dimensions 29' X 41.5' x 11' swd Detention Time (ADF) 18 minutes Flocculator Units: Type Vertical Shaft, Hydrofoil Number Per Basin 6 Rated hp 2 Clarification Basins Surface loading rate at 8 MGD per basin Number 3 Type Dissolved Air Flotation (DAF) Dimensions 29' X 39' X 11' swd Detention Time 17 minutes Surface Loading Rate 4.9 gpm/ft2 Skimming Mechanism: Type Reciprocating Number Per Basin 1 Rated hp 0.5 Recycle Pumps: Type Horizontal End Suction Number of Units 4 Common to all DAF Basins Capacity 556 gpm TDH 250 feet Rated hp 75 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-14 Item Design Data Notes Air Compressor System: Type Rotary Screw Number of Units 2 Capacity 45 scfm Pressure (Maximum) 125 psig Rated hp 15 Saturator Vessels: Type Vertical Number of Units 2 Vessel Diameter 6.5 feet Vessel Height 14 feet Packing Depth 4 feet Operating Pressure 60-90 psig DAF Float Pumps: Type Progressive Cavity Number 3 Capacity 34 gpm TDH 20 feet Rated hp 3 Filtration Number 4 Type Constant-head Media Mixed - anthracite/sand/garnet Surface Area, each 930 ft2 Loading Rate 5 gpm/ft2 Backwash: Wash Wafer Pumps Number 1 Filter loading rate with one filter offline Capacity, each 1,071 gpm Wash Water Supply Tank Type Welded Steel Diameter 36 feet Water Depth 25 feet Volume 190,000 gallons Recovery Tank: Type Concrete Diameter 65 feet Water Depth 25 feet Capacity 620,000 gallons Return Pumps: Number 2 Capacity, each 900 gpm City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-15 Item Design Data Notes Chemical Systems Polyaluminum Chloride Liquid Sumaclear 803B Storage Tanks Two at 10,000 gallons each Feed Pumps: Number, feed rate Two at 108 gph each Type Peristaltic, WM 624U Primary Coagulant Feed Range 1.8 to 216 gph total Average Dosage: Source: Reservoir 0.09 mg/L (active polymer) Source: Big Thompson 0.03 mg/L (active polymer) Aluminum Sulfate Storage Tanks Liquid Feed Pumps: Two at 7,000 gallons each Number, feed rate Two at 108 gph each Type Peristaltic, WM 624U Alternate Primary Coagulant Feed Range 1.8 to 216 gph total Average Dosage: Source: Reservoir 50 mg/L Source: Big Thompson 25 mg/L Cationic Polymer (Peak) Liquid Peak Poly Storage Tanks One at 100 gallons (storage); One at 30 gallons (day) Feed Pumps: Number, feed rate One at 186 maximum gph Coagulant/flocculation aid Type Progressive Cavity Feed Range 0 to 186 gph Average Dosage: Source: Reservoir 0.1 to 0.3 mg/L Source: Big Thompson 0.1 to 0.3 mg/L Caustic Soda (NaOH) Storage Two at 11,500 gallons each Feeder: Number, feed rate Two at 42 gph each pH adjustment Type Pulsa 880 Feed Range 0 to 84 gph Average Dose 15 mg/L Fluoride Storage Hydrofluorosilicic acid Feeder: 9,000 gallons Number, feed rate One at 12.75 maximum gph Type Pulsa 680 Background levels of fluoride are between 0.2-0.3 Feed Range 0 to 12.75 gph mglL depending on source Average Dose Source: Reservoir 0.7 mg/L Source: Big Thompson 0.7 to 0.8 mg/L City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-16 Item Design Data Notes Disinfection Type Liquid Sodium Hypochlorite Storage Tanks: Type Circular, FRP Number 4 Volume 1,875 gallons each Maximum Dose Range: Pre-DAF 5 mg/L Post-DAF 5 mg/L At 20 MGD Final Filtered Effluent 5 mg/L Metering Pumps: Type Gear Number 3 3 Capacity 0.6-5.5 gph 5.5-30.5 gph TDH 70 feet 70 feet Rated hp 0.5 0.5 Clearwell Number 1 Capacity 185,000 gallons Located below filters 1 and 2 Treated Water Storage Reservoir Number 1 Type Concrete, rectangular Capacity 2.34 MG Overflow Elevation 5,181 Water Depth 19 feet Treated Water Supply High Service Pumps: Zone 1 Pumps: Number 6 Capacity, each 2,800 gpm TDH 260 feet Motor hp, each 250 Residuals Handling Type Lagoons, Rectangular, Asphalt Lined Number 4 Dimensions 280' x 70' City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-17 Figure 1-3; Boulder Reservoir Water Treatment Facilitv Process Schema.f Boulder Reservoir Water Treatment Facility at 63`d St PWSia CO.010752 'Facility 002 Process Schematic 16 MGa Firm (20 Max) Capacity not to Scale - Rev. tl2-1 o VLJ Pre-PiL'~r Chlorine Three 8 MG0 F o cc,Yotion alb RM2 r - - - - - - - 1 Dk-i `w-0 Air FkaetatiQn (VA.) Vnils IRDSG1 I ; Pntlr l~~i Bert ~ Six zso hp 1 Media Post Fjllgr Chlt~aina RC70 S r tJ h?Gl}d EPW,2 °laker lied TT--- Fillers Sodium Hydroxide hlghserwicm ; TvG Hytlrafluorasale_i r.c um a In nree:rl sq ft ee P ~ 30 /F - t D 5 a5 _t *t I DRF ] OAF OAF Filter ' 1 id Alum } nl PACI - Filter CFE{302 ad`s t' Intake 005 r Disbibutian Pre-chlorins - R401 Systern Each can ke allied IF RaFid Mix ar Stalk' Mu w s IL F l ~ IIt2r x , NtlX9r P I : - . - e4' Sergi,,43 IIr,9 w rllp I' Rapid Pdix. ~r~nnliary ~ sjnaw~~d L-:_-- F-gr~l i I Lagoons ' a:atl: h'Ik' I Filler 8ackf►'nsM1 ;Ll r ly 'a-11. H21-'O3 - .:311 mir-- pnlparl - Wa16r o f+ FIr-dlo'•iLers -.04 61'yn46r V +-5 C C21 . vptonal w w rQ~ItSli91 - J 'aler Y ResldrJal PlBril rr, yr la *Alrr Cipliewiz • ter Head; of ~YlAllf, L TOC fFcy'!lE' t I primary rN Seco-nda la cmaz, or sewer CvQrflrnv - arf k yI Re! i"19 opoon9 • m pipory &yng 4 r V. 7rix.srrrxlwyII.gw.nx. nrxrracr t 2.34 IVIG Clearwall CW003 - • -►Y- _ _ _ _ _ _ _ _ _ _ I Serpentine baring { Lagoon 1 State assigned 0.7 baffling factor Four-F.ritmry I Lz1{ 7rni ; Residuals Lagoons ~ Decont noons - re-covery lank, ! 75 i' X8(1 mccm.,sry aaoons, oa se%ver _ P. - - - - - Boulder Lagoon ;f R_5=f,, •,f ~l ac2~E .j f Ili .it Jti I t.iA.r: 1111 + - - - ` NPDES DIsmarge Permit Na. COG-6410010 I r-mll.ilp No. COG -641073 (rev. 1-9-06P NOTES; Ree dots denote flaw nt aasL?ramam ~lulf II001 A - Discharge from drains and nvarflows I r-------- - Ciseruell, RecycJe4WalerRewvary-lagoonsand Rai';°isier FUnl~x Poik arraws art- Sarnpling Pornl-i 1 h?NDa and DAF overflow prior toeniedrtg Little Dry Creek, ;mac 0 f.u;p, NPOES Di5t.har9e OwtFall OG2 was OFArninated in 2004 DrIL! 4 MGM rip;e-m~1 i 5eg d of the St Vraln Creek Sub-basin, South Platte j Rlvr>r Bar9m Industrial Waslewater Discharge Permit 2DOS-T - ._.-.-.-._._.-.-.-._._.-.-.-.-.-.-.-.-.-.-.-.-.-.-.I I Options: Lagoon Decant, Rec:yGle Vvel,~r, aroiror J Rrusl+9u;iiil I~IRr:ISaiiyr. Isi', ~ 4'i"~= fJ f L_ Ile Dry Creek going tG dry Creek ~~-`rs-s 1y City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-18 2.2.2.1 Raw Water Intakes Raw water can be brought into the BRWTF in two ways, by diverting it from the BFC or by pumping from Boulder Reservoir. Direct diversion from the canal is preferred because water will flow to the plant by gravity, which saves the cost of pumping from the reservoir. The quality of the water diverted from the canal is also generally better and easier to treat. The City has investigated options of replacing the BFC with a pipeline directly from Carter Lake. This would further improve source water quality. The BFC only operates during summer months, requiring the BRWTF to use water from Boulder Reservoir when the BFC is offline. Raw water from the BFC is diverted through a bar screen set into the side of the canal channel. The screen is manually cleaned and requires an operator to inspect and clean it several times per day. Water is conveyed to the plant by gravity in a 42-inch pipeline. Alternatively, water can be pumped from the reservoir by vertical turbine pumps that draw water through an intake strainer mounted in the reservoir. The intake strainer was recently replaced with a fixed level intake that enhances operator flexibility in avoiding certain seasonal raw water quality problems such as algae or manganese. 2.2.2.2 Flocculation/Clarification In 2005, the single flocculation/sedimentation basin was removed and replaced with two new flocculation and DAF clarifier trains. This work included the installation of a 42-inch influent pipe, insertion style flow meter, flash mixing, static mixer, and a flow splitter box to feed each of the trains. In 2010, a third flocculation/DAF train was added to improve plant redundancy. Since the DAF trains were installed, the effluent turbidity has significantly improved from a typical value of 2.5 NTU to less than 1.0 NTU. The DAF basins also provide much higher solids concentration as compared to the old flocculation/sedimentation basin, which eases the load on the residuals handling process. 2.2.2.3 Filtration There are four filters, two built with the original plant in 1972, and two built when the plant was expanded in 1998. Filters are mixed media, garnet and silica sand with anthracite cap. Operations Staff report that media loss during backwashing is not a problem. Two filters are used when the plant is operating in the range of 3.5-8 MGD. A third filter is put on line when the treatment rate goes above 8.5 MGD. The fourth unit is kept clean and ready for service when another unit requires backwashing. Water for backwashing the filters is pumped from the finished water clearwell to a backwash reservoir. Backwashing is accomplished by gravity flow from the reservoir. A surface wash system is also installed on each filter. Backwash water and various plant drains are routed to a recovery tank which is pumped back to the head of the plant without any additional treatment. In 2010 yard piping improvements were made to allow for the backwash water to be pumped to the residuals lagoons. During the design of the DAF system, consideration was given to discharging backwash water to the sanitary sewer system rather than recycling it to the head of the water treatment plant. However, permitting issues related to this disposal method prevented it from being implemented. The filters currently do not have filter to waste capability. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-19 2.2.2.4 Chemical Addition Chemical systems include facilities for the addition of the following chemicals: • Carbonic Acid > Raw water pH adjustment for enhanced coagulation by stabilizing the influent pH and improved TOC removal > Stored as liquid CO2 in 60 ton outdoor tank > Fed at chemical injection vault in yard > PLC controlled flow pacing and pH trim • Polyaluminum Chloride (Sumaclear®) > Primary coagulant > Stored and fed as liquid > Fed either at the flash mixer or the static mixer prior to the flocculation/DAF train flow splitter box > Manually controlled flow pacing from SCADA • Aluminum Sulfate > Alternative primary coagulant > Stored and fed as liquid > Fed either at the flash mixer or the static mixer prior to the flocculation/DAF train flow splitter box > Manually controlled flow pacing from SCADA • Cationic Polymer (Peak) > Coagulant/flocculation aid > Stored and fed as a liquid > Fed at the flocculation/DAF train flow splitter box > Manually controlled pump speed from SCADA, no flow meter • Sodium Hypochlorite > Fed at Pre- or Post-DAF locations > Fed after filtration for disinfection and to maintain a residual out into the distribution system > PLC controlled flow pacing and chlorine residual trim • Fluoride > Fluoride is added to the water after filtration > Liquid Hydrofluorosilicic acid is stored in a single tank and added to the flow in the finished water flume > Manually controlled flow pacing from SCADA • Sodium Hydroxide > Raw water contains sufficient alkalinity that supplemental alkalinity addition is not required. Final pH adjustment using caustic soda is the only chemical stabilization adjustment made for corrosion control. > PLC controlled flow pacing and pH trim City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-20 • The City has recently installed a temporary sodium permanganate (NaMnO4) feed system at the Raw Water Pump Station to assist with taste and odor and manganese removal from the Reservoir water. Insufficient information is available at this time to assess the effectiveness of this system. • Chemical Mixing > Mixing of treatment chemicals with influent flow utilizes a mechanical pumped diffusion flash- mixer followed by a static mixer- > The application points for final chlorination, fluoride, and sodium hydroxide are located in the 42-inch plant effluent pipe, which was designed for an ultimate plant flow of 24 MGD. However, since the current plant flow rate is typically in the range of 3.5-8 MGD, velocities in the pipeline are low resulting in poor mixing. 2.2.2.5 Finished Water Storage and Pumping Finished water flows by gravity to a 2.34 million gallon concrete finished water storage reservoir located on the plant site. The original plant construction included an 185,000 gallon clearwell located below filters 1 and 2. No additional clearwell was built when the new filters 3 and 4 were added. Flow from filters 1 and 2 is piped to the clearwell while the effluent piping from filters 3 and 4 is connected to the clearwell outlet pipe such that it flows directly to the finished water storage reservoir without passing through the clearwell. In 2005, baffles were installed in the 2.34 million gallon finished water storage reservoir in order to allow the operational flexibility to operate the clearwell at lower levels while continuing to meet the requirements of the Colorado Department of Public Health and Environment (CDPHE) with respect to clearwell detention time, and to meet the City's own 1.5-log Giardia removal goal using disinfection. Water is pumped from the finished water storage reservoir into Zones 1 and 2 of the water distribution system by high-service pumps located on the plant's lower level. There are six pumping units, three installed in 1972 when the plant was originally built, the fourth installed in 1996 when the new filters were added, and fifth and sixth installed in 2005 with the DAF pretreatment improvements. All of the pumping units are constant speed, horizontal split case type, rated for 2800 gpm. All treated water produced at the BRWTF is pumped into the distribution system. This is the main reason the cost of treated water from the BRWTF is approximately twice the cost of treated water from the BWTF. This cost differential is a dominating factor, along with water quality, in determining plant production and water resource usage. 2.2.2.6 Residuals In 2005, four asphalt lined residuals lagoons were construction on the west end of the site. Sludge is wasted from a single float channel located at the end of the three DAF trains and is pumped from the channel using progressive cavity pumps which discharge to the lagoons. A second, and utilized as an emergency sludge discharge point, is to the City's wastewater system, which flows by gravity to the IBM lift station and is lifted to the 75th Street Wastewater Treatment Plant (WWTP)_ City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-21 2.3 Treated Water Distribution System Treated water is distributed to customers throughout the City's service area by a system of buried pipes. The City has over 400 miles of distribution piping. Most of the piping was installed in the 1950s through the 1970s and was typically cast iron pipe and ductile iron pipe. The distribution system also includes facilities for controlling pressure within the system, storing water to provide reserves for peak demand and emergency situations and for the generation of electricity using excess pressure in the system. The Water Utility Planning Area and associated distribution system is shown on Figure 5-4. Figure 5-5 shows a schematic of the water distribution system and associated zones. Elevations within the City's service area range from approximately 5,150 to 5,750 feet. To facilitate the maintenance of water pressures within an acceptable range in all parts of the system, the distribution system is divided into three zones based on topographic relief. The approximate service elevation range for each zone is as follows: Zone Service Elevation (USGS Datum) 1 Up to 5420 (approximate elevation of Gunbarrel storage tank overflow) 2 Up to 5615 (approximate elevation of Kohler/Maxwell storage tank overflows) 3 Up to 5852 (approximate elevation of Chautauqua, Devil's Thumb, and Booton storage tank overflows) In general, Zone 1 includes the east and northeast sections of the service area. Zone 2 covers the largest portion of the service area including the downtown area and the University of Colorado. Zone 3 extends along the west side of the service area. Zone 3 is separated by lower Zone 2 elevations along Boulder Creek. Pressure reducing valves (PRVs), hydroelectric generators, and pumping facilities allow the controlled flow of water between the various pressure zones. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-22 P NO...I Ile Boulder Reservoir WTP 8 a BOOTON EL 0 O P.n.art A. _ To MAXWELL r ♦ TANK ' Iris Pump a ~ 4d.P.xlenu q.P.ul ~11+~ kY AV - ++1 ,yfa YaN'A^IP4 ] ~Yelnp°}RE 4 EEPApOAG~ VaNaA M p~I"- PaIP.TAa ~ '^51Me CppPM f 1 a P^tlE~ rary~ To Betass WTP _ ~ ` MPM,oeb ~ ~ Pale ArePance N O F L46-14 AY \ I ILW rtE k.% J NO' ~ v `~herryvaie CHAUTAUQ Pump O 3-ewa. Ad BauIM1 PME.M ONM°Y ~ J u v G-06., Oil - THUMBO Legend N O Tanks BVCP Area Boundaries Water Pressure Zones n O Pumps Area 1 F Zone 1 N ■ Water Treatment Plants Area II ~ Zone 2 Water Utility Planning Pipes, 12 inches or greater Area III Zone 3 Water Utility Study Area Boundary and 0 Area Boundary BVCP Area Boundaries , z MLNH Miles Map l Figure 5.5; MOKVELD PRV BARKER RESERVOIR LAKEWOOD RESERVOIR KOSSLER RESERVOIR ` L____I - ""''''"'I I CW #1 CW #2 j BOOTON ~ I - I VOL: 2.5 MC VOL; 1.7 MG VOL: 3.5 MG LAKEWOOD HYDROI HWL: 6385.0 HW6385.0 HWL: 5852.0 I_________ I BETASSO WATER WATER DEPTH!, 34FT WATER DEPTH: 34FT WATER DEPTH: 21FT IBOULDER HYDROI 1 I I TREATMENT F_ANT I DEVILS THUMB CHAUTAQUA I I I I ----------1 I I VOL: 5.0 MG VOL: 8.0 MG 1 I I I HWL 5851,8 HWL: 5853.2 1 WATER DEPTH: 2118 WATER DEPTH: 25.1Fr I 1 I I I BETASSO HYDRO ---------------J WI I---------------------- I I a I ZONE 3 OROOEII HYDRO ----S(1NSHINr PSV - ZONE 2 - F,:r , 70NF 3 1 1 1 ZONE 2 KDIILCR I I ORDDELL PRV I I I r2 I I I K01-11 FR HYDRO I Vol- SA MC I.M. hdin.fi 101 - PEARL F- WATCR D_Pnl' 23.7rt . 1 I MAXWELL r. a~ 1 - - - - I I I I 40_t 9.5 140 I SUNSHINE HYOR(1 3 1 5G15.6 I WATER CEPTH: 22,5FT ~ I I 02 ! I - I I KQIILLR PRV - MAXWELL PRV li 11 I ZONE 2 ZONE t CHERRYVALE PUMPING STATION ITS PUMPING STATIDN #2 _j 11 i MAXWELL HYDRO L - 7nNF 2 ~ r2 i ZONE I I GUNBARREL #3 1 I HDDIDFR -?6"hHVOIH VOL; HWL 2.0 uG HWL 5 I VOL: 4170 MG I I WATER DEPTH : 20FF I I L_____________I I { g7 r.T ~4 1 i IRIS PUMPING STATION #1 Ei~ " 1 ----I I - - - - - - - - - - - - - - BCuEDER RESERVOIR 1 (63rd STREET) 22 WATER TREATMENT PLANT 1 I - 8(IULDER j CANAL r3 I I FEED=R I I I I I r4 ~ I I I I I Y5 --------------1 I I I ~6 I I I - - - - - - - - - - - - - - City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-24 Treated water is conveyed to the distribution system by gravity from the BWTF and by pumping from the BRWTF. In general, water from BWTF feeds into Zones 2 and 3. Zone 1 is fed primarily from the BRWTF with supplementary flow from BWTF through Zone 2. Recent improvements to the pipes and pump stations fed from the BRWTF allow better distribution of water from Zone 1 into Zone 2, which enlarges the area that can be fed from the BRWTF. The BRWTF can deliver treated water to Zone 1. The facility is located in the northeast side of town and it delivers treated water into this area of town. It also can be delivered to the remaining portion of the distribution system via two transmission mains. A 16-inch line runs adjacent to the Diagonal highway from the plant to the Iris Pump Station #1 and Iris Pump Station #2. The other is a 24-inch main that connects the plant to the Cherryvale pump station. The recent improvements to those systems allow more flexibility in pumping to either Zone 1 or Zone 2. Water from the BWTF is conveyed to the City's distribution system by two major transmission mains. One pipeline follows Boulder Canyon and the other enters by Sunshine Canyon. Both pipelines originate at the BWTF clearwells and are individually metered. The accuracy of these flow meters has been questioned. Replacement of the existing meters with new factory calibrated units would be necessary to achieve certifiable accuracy. Parts of the Boulder Canyon pipeline were used to transport water into Boulder before the BWTF was constructed- Sections of this line were constructed of pipe manufactured before the turn of the century (1896). From the BWTF, a 24-inch pipeline runs to the Orodell Hydroelectric/PRV station where pressure is reduced. In the early 2000's the original pipe that was still in service below the Fourmile PRV station was rehabilitated by lining with high-density polyethylene pipe. A new control valve was installed at the Orodell Hydroelectric/PRV station to provide backpressure to the turbine as well as two turbine bypass control valves and the Fourmile PRV station was abandoned in 2005_ This effectively increased the capacity of the Boulder Canyon Pipeline to approximately 20 MGD. The City of Boulder's 2008 Utilities Division Annual Report summarizes the testing of the capacity of the Boulder Canyon pipeline. The following is an excerpt from the report: "The capacity of the Boulder Canyon Pipeline was determined in order to facilitate taking the Sunshine Canyon pipeline out of service for inspection. The Sunshine Canyon Pipeline has been in continuous service since it was constructed in the 1970's. To take the Sunshine Canyon Pipeline out of service, the Utilities Division has estimated that we will need to be able to move 20 MGD through the Boulder Canyon Pipeline. A bypass pressure reduction valve station was added outside the Orodell Hydro Station to allow more water past the hydraulic restriction at Orodell but the capacity of the pipeline was not fully tested. To move 20 MGD down the Boulder Canyon Pipeline, pressures higher than those initially set in the controls of the bypass pressure reduction valve were needed. The controls were adjusted and the flow test completed during high system demands in July 2008. The flow test was conducted up to downstream pressure of over 100 psi which corresponded to flows of over 17 million gallons per day without noticeable vibration or cavitation in the bypass valves. However, at that point in the test the existing internal bypass and the external bypass valves needed coordinated adjustment to continue to increase the flow through the external bypass valve. At this point the test was concluded to ease reinstatement of normal operation. " City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-25 The Sunshine Canyon pipeline conveys water from the BWTF into Zone 3. This welded-steel, 30-inch pipeline was built at the same time as the BWTF making it about 45 years old. Pressure and flow are regulated at the Sunshine Canyon Hydroelectric and PRV stations. After reducing pressure from the BWTF through the Orodell and Sunshine Hydro/PRV stations, water flows through a series of transmission pipes into Zone 3 storage tanks, Booton (far north), Chautauqua (central), and Devil's Thumb (far south). Zone 2 is fed from Zone 3 through PRVs at the 101 Pearl station near the downtown area, and at Maxwell in the north and Kohler in the south. It is also fed from Zone 1 via the Iris and Cherryvale pump station in the northeast and southeast respectively. The following discussion provides descriptions of the major facilities in the water distribution system. A summary of facility characteristics is provided in Table 5-4. Table 5-,:,: 1r,- Ater System F 7~esign Data Item Design Data Notes Pressure Reducing Stations Zone 3 Sunshine PRV Two at 6-inch Bailey Polyjet@1 One bypass PRV in Hydro building Bypass vault piping was recently modified, but not Orodell PRV Two smaller PRVs in separate the PRV vault. A PRV was installed upstream near PRV structure outside. Boulder Hydro for Betasso Hydro capacity testing and it discharges raw water to Boulder Creek. Zone 2 101 Pearl PRV Two at 10 inches, Bailey Polyjet'D Kohler PRV One at 8 inches and one at 10 inches Bailey Maxwell PRV One at 8 inches and one at 10 inches Bailey Zone 1 Iris #1 constructed 1996, electric controls installed in Iris #1 PRV One at 8 inches and one at 2 inches 2010 and 8 inch PRV internal parts and gasket replaced Iris #2 PRV One at 8 inches and one at 2 Iris #2 constructed in 2010 inches Cherryvale PRV One at 8 inches and one at 2 Cherryvale PRV was not updated as part of 2010 inches refurbishment. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-26 Item Design Data Notes Hydroelectric Stations Zone 3 Sunshine Hydro Upstream Pressure 300 psi Downstream Pressure 75 psi 2009 usage: 3,007,938 kWh ($84,397 in revenue) Pump/Turbine Units 1 Capacity 800 kW Orodell Hydro Upstream Pressure 220 psi Downstream Pressure 42-120 psi 2009 usage: 700,343 kWh ($25,897 in revenue) Pump/Turbine Units 1 Capacity 200 kW Zone 2 Kohler Upstream Pressure 112 psi Downstream Pressure 6 psi 2009 usage: 708,208 kWh ($29,324 in revenue) Pump/Turbine Units 2 Capacity 120 kW Maxwell Upstream Pressure 104 psi Downstream 6 psi 2009 usage: 541,606 kWh ($22,896 in revenue) Pump/Turbine Units 1 Capacity 90 kW Zone 1-N/A Pump Stations Zone 3 NCAR Zone Boosts Zone 3 pressure into Part of private system. private system Pumps Pumps run in lead/lag mode after 10:30 pm to fill a Number 2 300,000 gallon tank with 250,000 - 275,000 gallons TDH 450 feet of water for use the following day. Rated hp, each 60 Zone 2 to 3 Kohler Emergency use only. Pump/turbine units can Turbine/Pumps: normally operate in parallel as turbines when Number 2 reducing pressure from Zone 3 to Zone 2. Capable of operating in series to pump water from Zone 2 to Rated hp, each 83 Zone 3. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-27 Item Design Data Notes Maxwell Pump/Turbine: Number 1 Emergency use only. Pump/turbine unit normally Capacity, each 1,550 gpm operates as a turbine when reducing pressure from TDH 221 feet Zone 3 to Zone 2. Capable of operating in series Rated hp, each 125 with the booster pump to move water from Zone 2 to Booster Pump: Zone 3. Number 1 Rated hp, each 40 Zone 1 to 2 Iris #1 Pumps: Number 2 Capacity, each 1,688 gpm TDH 240 feet Rated hp, each 150 Rpm 1,780 Iris #2 Pumps: Number 2 Capacity, each 1,688 gpm TDH 240 feet Rated hp, each 150 Rpm 1,780 Cherryvale Pumps: Number 3 Capacity, each 1,688 gpm TDH 240 feet Rated hp, each 125 Rpm 1,780 Zone 1 Boulder Reservoir Pumps: Number 6 Capacity, each 2,800 gpm TDH 260 feet Rated hp, each 250 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-28 Item Design Data Notes Storage Reservoirs Zone 3 Devil's Thumb Type Welded Steel Capacity 5.0 MG Overflow Elevation 5,851.8 ft above sea level Water Depth 21 feet Chautauqua Type Concrete Capacity 8.0 MG Overflow Elevation 5,853.2 ft above sea level Water Depth 25.1 feet Booton Type Welded Steel Capacity 3.5 MG Overflow Elevation 5,852 ft above sea level Water Depth 21 feet Zone 2 Kohler Zone 2 Type Concrete Capacity 9.4 MG Overflow Elevation 5,610.5 ft above sea level Water Depth 23.7 feet Maxwell Zone 2 Type Concrete Capacity 9.5 MG Overflow Elevation 5615.6 ft above sea level Water Depth 23.5 feet Zone 1 Gunbarrel Type Welded Steel Capacity 2.0 MG Overflow Elevation 5,420 ft above sea level Water Depth 20 feet 2.3.3.1 Orodell Hydroelectric Station and PRV This facility is located in Boulder Canyon approximately four miles west of the City. Hydroelectric power is generated from the pressure in the Boulder Canyon finished water line from the BWTF. A bypass PRV is independent of the hydroelectric station and allows water to flow around the Orodell station and down the canyon. The upgraded bypass PRV allows the Boulder Canyon pipeline to be able to carry up to 20 MGD at all times. The upgrade to the bypass vales include: two "Roll Seal" control valves installed at the Orodell Hydro 12" bypass in an aboveground structure along Boulder Creek. The structure, fabricated by Engineered Fluid, Inc. in Illinois was trucked to the hydro site is a tilt-back hinged design with electric controls and a thermostatically controlled heating unit. Prior to this installation, water was running into the City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-29 Orodell meter station vault. Two leaks were detected in the 24" high pressure steel transmission line upstream and repaired as part of this project. (City of Boulder 2005 Utilities Division Annual Report). Equipment in the Orodell Hydro Station includes a turbine and generator system, turbine isolation plug valve, bypass PRV valve, bypass upstream and downstream isolation butterfly valves, downstream flow control valve, miscellaneous valves and piping, and a battery back-up and charging system for instrumentation and control (I&C). The FourMile Valve House was abandoned, and a new butterfly valve installed upstream, to facilitate the planned conversion of the 16" Zone 3 steel transmission pipe into Zone 2 use. A new air relief valve was installed on the existing Zone 2 line. (City of Boulder 2005 Utilities Division Annual Report). 2.3.3.2 101 Pearl PRV Station This facility was built in 1996 to replace the 6th and Canyon PRV station. The station consists of two 10- inch, 150-psi, and Bailey sleeve valves, which operate during summertime peak flow months to reduce pressure on flow transferring from Zone 3 to Zone 2. Flow is shut off during off-peak months, which eliminated this as a potential hydroelectric generation site under current operation. The facility was set up to allow installation of a hydro generator if future operations make it economically viable. 2.3.3.3 Sunshine Hydroelectric Station and PRV The hydroelectric facility is located on the Sunshine Canyon line, the main transmission line from the BWTF to the City. A PRV had been installed at this location when the pipeline was built and the hydroelectric generation facility was constructed in 1986 to make use of the available energy. The hydroelectric generation equipment consists of an 800 kW Francis turbine, an induction generator, a 20- inch ball type isolation valve, turbine bypass PRV and necessary electrical, instrumentation and control gear. This facility operates continuously except during maintenance operations. The PRV facility is located adjacent to the Sunshine Hydroelectric Station. The PRVs control bypass-flow around the hydroelectric facility and reduce pressure in the Sunshine Canyon line to Zone 3 pressure. This facility predates the hydroelectric facility and originally was the main PRV on the Sunshine Canyon line from BWTF into the City. During a complete renovation, begun in 1996 and completed in 1998, the original 16-inch motor operated plug valves were replaced with Bailey Polyjet® sleeve valves. Valve controls allow for remote control through the City's System Control and Data Acquisition (SCADA) system or local control to maintain a pressure set point via a local PLC. The 1996 renovation also provided for improved access to the vault by replacing the original manhole access with a walk-in door. This improved operator safety by replacing ladder access with walk in entry, eliminating a confined space entry and providing for faster emergency egress, and made it generally easier for operations staff to inspect and maintain this critical facility. 2.3.3.4 Devil's Thumb Reservoir The Devil's Thumb Reservoir provides storage and surge protection to the southern portion of Zone 3. The 5.0 MG reservoir is a fully enclosed welded steel tank sitting at grade. The overflow level is elevation 5851.8. A single 30-inch pipeline serves as both inlet and outlet to the tank. The water level in the tank floats without regulation by a control valve. Only a manual isolation valve is provided in a vault adjacent to the tank. Valve operation and status cannot be accessed through the SCADA system. 2.3.3.5 Chautauqua Reservoir Chautauqua Reservoir is an 8.0 MG covered concrete tank partially buried in the hillside. This facility provides storage and surge protection to the central portion of Zone 3. The reservoir overflow level is elevation 5,8532. The reservoir is connected to the system by an 18-inch inlet/outlet line with an altitude City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-30 valve to control flow. The altitude valve can be adjusted remotely via the SCADA system. Other piping associated with the reservoir includes: • 12-inch cast iron siphon inlet/outlet fitting that penetrates the wall near the top and terminates several feet above the reservoir floor and a 12-inch motor-operated valve • 12-inch steel siphon in the northeast corner, which penetrates high on the reservoir wall and terminates several feet above the reservoir floor • 12-inch cast iron bottom inlet/outlet in the northeast corner • 14-inch steel floor drain in the northeast corner, which discharges to a nearby creek 2.3.3.6 Booton Reservoir Booton Reservoir is located at the extreme north end of Zone 3, and provides storage and surge protection. The tank is circular, welded steel construction, built as a "tank within a tank" jointly by the City and Pinebrook Hills Water and Sanitation District. The center portion of the tank is separated from the outer, annular portion by an inner wall and piping is arranged to provide separate connections to each system. The Pinebrook Hills District uses the inner tank while the outer, annular space provides the City with 3.5 million gallons (MG) of storage. The design maximum water level is elevation 5,852.0 at a water depth of 21 feet. 2.3.3.7 Zone 2 The Maxwell and Kohler facilities are complementary, serving similar functions at the northwest and southwest corners of Zone 2. These facilities generate electricity from the pressure differential between Zone 3 and Zone 2 using generation units comprised of centrifugal pump units adapted to "run backwards" to generate electricity by driving an induction generator. Under extreme emergency conditions such as a major fire in Zone 3 or an interruption in operation at the BWTF, the generator units can be used to pump water from Zone 2 to Zone 3. These two facilities generate a significant amount of electricity continuously year round. At each facility, a bypass PRV allows flow in excess of turbine capacity to bypass the facility and pass directly to the reservoir. 2.3.3.8 Maxwell Reservoir and Hydroelectric Facility The Maxwell facility is located at the base of the foothills in the northwest part of the City. This station has one generator/pump unit and one pump only unit. Under normal operating conditions the Maxwell pump/generator operates to generate electricity and the pump unit is in standby isolated by valves. Under emergency conditions, the two units would operate as pumps in series to produce enough pressure to move water from Zone 2 to Zone 3. The station bypass is located in a separate vault. A 1998 upgrade replaced the original motor operated plug valve with a 10-inch Bailey sleeve valve in a separate vault. Maxwell reservoir is a 9.5 MG underground concrete tank with an overflow level of 5,615.6. 2.3.3.9 Kohler Reservoir and Hydroelectric Facility The Kohler facility is located at the base of the foothills in the southwest part of the City. This installation has two generator/pump units. In normal operation, both units operate in parallel to generate electricity with flow passing from Zone 3 to Zone 2. Under emergency conditions, the two units would operate as pumps in series to produce enough pressure to move water from Zone 2 to Zone 3. A 1998 upgrade replaced the original motor operated plug valve with a 10-inch Bailey sleeve valve. A new vault was constructed for the new bypass valve. Kohler reservoir is a 9.4 MG underground concrete tank with an overflow elevation of 5,610.5. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-31 2.3.3.10 Zone 1 Zone 1 is supplied with water from the BRWTF by the plant's high service pumps. The Cherryvale and Iris pump stations allow water to transfer between Zones 1 and 2. Water will pass from Zone 2 into Zone 1 when the BRWTF is not operating or when Zone 1 demand exceeds the output of the BRWTF. PRVs in the stations control the flow and the pumps remain off. Originally the PRVs had motorized pilot valves, which have been removed and the valves set for Zone 1 pressure. The pumps can be used to transfer water from Zone 1 to Zone 2 optimizing use of water resources by making C-BT water available to Zone 2 as well as Zone 1 _ 2.3.3.11 Cherryvale Pump Station and PRV The Cherryvale Pump Station is located in the southeast part of the system and receives water from BRWTF. This station houses three identical horizontal split case pumps arranged for parallel operation to transfer water from Zone 1 into Zone 2. Recent modifications (2010) to this pump station included the replacement of the three pumps and improvements to the electrical service system. The Cherryvale PRV is used to transfer Zone 2 water into Zone 1 when required. 2.3.3.12 Iris Pump Stations and PRVs The Iris Pump Stations are located in the northeast part of the system and also receives water from BRWTF. In 2005, the pumps were replaced in the original pump station. This, along with the new 24-inch pipeline along the Diagonal Highway, allowed BRWTF to deliver up to 12 MGD and allowed transfer of water from the BRWTF into the western part of the distribution system. In 2010, a second, "sister" pump station was added (Iris Pump Station #2) increasing BRWTF distribution delivery capacity. Each pump station houses two, identical, horizontal, split-case pumps rated at 1,688 gpm, at 240 TDH and are driven by 150 Hp, 1,785 rpm, constant speed motors. The Iris #1 and Iris #2 PRVs are used to transfer Zone 2 water into Zone 1 when required. 2.3.3.13 Gunbarrel Reservoir Gunbarrel Reservoir provides storage and surge protection to Zone 1. Located in the extreme northeast corner of the zone, the 2.0 MG reservoir is a fully enclosed welded steel tank sitting at grade. The overflow level is elevation 5,420.0. The following list summarizes the water distribution system components that comprise the City's treated water system. The 2010 data was taken from the City's Geographical Information System (GIS). • Water Distribution System Piping 475 miles (23 miles are owned and maintained privately) • Valves 6465 • Fire Hydrants 4624 • Steel Pipe Corrosion Protection Devices 70 • Water Meters and Accounts 28,773 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-32 2.4 System Control The operation of the water distribution system is monitored at the BWTF by means of the system-wide SCADA system. This system provides for continuous monitoring of all, pressure reduction valves, system pressures, storage reservoir levels, and hydroelectric generation units and pump operations. The system also provides for remote control of most of the pressure reducing valves, bypass valves, pumps and generators in the system such that the operators can largely control the distribution of treated water within the system from BWTF. As presently configured, the SCADA system does not provide for automatic operation of any of the systems facilities. The SCADA system does, however, provide for the recording of detailed operating data. 2.5 Current Staffing Day to day operation of the treated water facilities is performed by employees of the City of Boulder Utilities Division of the Public Works Department. Personnel from several different funds and programs directly provide services that are essential to the overall operation of the system. Table 5-5 shows the staffing levels for the Water Fund. In total, the Water Fund includes a total of 75.13 full time equivalent (FTE) positions. In addition, the Utilities have Wastewater, Stormwater, and Transportation Funds (not shown in table) that along with the Water Fund in total comprise 155.90 FTEs. Title FTE Program FTEs Admin - Water 2.13 Director of Public Works 0.40 Financial Manager 0.35 Admin Specialist II 0.35 Project Admin. 0.40 Rate/Data Analyst 0.63 Billing Services -Water 2.85 Supervisor 0.54 Representative 2.00 CIS Support 0.31 Support Services - 510 0.64 Communication Specialist 0.20 Communication Coordinator 0.14 Administrator 0.30 Engineering Ops - Water 5.76 Draftsperson II 0.60 Engineering Project Manager 2.50 Admin Specialist 1 0.08 Admin Specialist II 0.40 Admin Supervisor 0.18 Senior Engineering Tech 2.00 Water Resources Operations 2.00 Water Resources Coordinator 1.00 Water Source Specialist 1.00 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-33 Title FTE Program FTEs Watershed Operations 2.00 Water Source Manager 1.00 Water Source Operations 1.00 Hydroelectric Operations 3.00 Hydro Tech. II 2.00 Hydroelectric Manager 1.00 BWTF Operations 13.75 Industrial Mechanic 2.00 Treatment Plant Supervisor 1.00 Plant Operator A 2.00 Plant Operator B 1.00 Admin. Specialist II 0.75 Chief Plant Operator 5.00 Lead Mechanic 0.50 Treatment Plant Coordinator 0.50 Process Optimization Specialist 1.00 BRWTF Operations 9.25 Industrial Mechanic 1.00 Chief Plant Operator 2.00 Treatment Plant Supervisor 1.00 Admin. Specialist II 0.25 Plant Operator D 1.00 Lead Mechanic 0.50 Plant Operator A 2.00 Treatment Plant Coordinator 0.50 Process Optimization Specialist 1.00 System Controls 3.00 Electronics Tech II 2.00 SCADA System Admin. 1.00 Water Quality Operations 6.78 Water Quality Planner 0.10 Water Quality Project Manager 1.00 Water Source Operations Manager 2.00 Water Quality Coordinator 0.20 Drinking Water Quality Lab 1.00 Water Quality Inspector 1.00 Admin_ Specialist II 0.20 Laboratory Supervisor 1.00 Analytical Chemist 0.20 Watershed Educations Specialist 0.08 Water Conservation 1.66 Water Quality Planner 0.10 Water Quality Coordinator 0.20 Program Specialist 1.00 Admin. Specialist 1 0.20 Watershed Outreach Coordinator 0.16 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-34 Title FTE Program FTEs Distribution System Maintenance 14.95 Maintenance Person 1 1.00 Maintenance Person II 2.00 Maintenance Person III 3.00 Maintenance Person IV 3.20 Maintenance Supervisor 1.00 Utility Maintenance Coordinator 0.20 Program Planner 0.60 Standby Utility 0.50 Utility Locator 1.00 Material Supply Specialist 0.80 Valve Operator 1.00 Admin. Specialist II 0.45 Program Admin. MGR 0.20 Meter Operations-Water 7.36 Meter Service Tech 5.52 Meter Service Operations 0.92 Shop Water Meter Service Tech 0.92 Total Water FTEs 75.13 The 2005 Lafferty and Lauer AWWA Benchmarking Performance Indicators for Water and Wastewater Utilities: Survey Data and Analyses Report provides a benchmark for the number of employees per MGD treated. This data, and a comparison for the City of Boulder can be found in Table 5-6. Table 5-6 Compa o f ! nnpicJ City of Boulder AWWA "All" AWWA "West" Performance Actual for Year 2009 Participant Median Participant Median Water Treated Per Employee' 0.29 MGD/FTE 0.25 MGD/FTE 0.29 MGD/FTE 'Water Treated = year 2009 annual average daily water treated of 22 MGD (12 MGD from BWTF and 8 from BRWTF) and Employees = 75.13 (year 2009 water fund FTEs). This comparison shows that the City of Boulder's 2009 data is near the averages reported in 2005 from AWWA's study. It is important that the City of Boulder continue to devote resources to workforce planning. While the existing staffing levels and distributions are appropriate for the City's needs, several factors in today's labor market are converging to create significant problems in the utility workforce. A mass exodus of utility employees is expected to occur due to retirement in the next 10 years and fewer U.S. college graduates are earning science or technical degrees than ever before, despite the fact that utilities are understaffed most particularly in engineer and operator positions. As more and more components of the City's water supply, treatment, and distributions systems are being automated and becoming more focused on Instrumentation and Control, it is becoming more crucial to find the right person for the right job, and to have systems in place to transfer knowledge to new staff. As stated in a February 3, 2009 AWWA Streamlines article (Volume 1 Number 3), the highest workforce development challenges for Water Utilities are: City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-35 • Recruitment and selection • Knowledge retention • Classification issues and staff training. This can be difficult during a weakened economy when budget cuts are on the rise. Indications are that utilities, instead of laying off workers, tend to be striving to keep up with attritions due to the high number of retirees. The State's Public Employees' Retirement Association (PERA) has indirectly assisted the City of Boulder in retaining and transferring knowledge within the City. Many of the employees that retire are able to come back to work after a set amount of time under the PERA program and work for 110 days per year. This has enabled the City to bring some retired employees back into the work staff in order to assist in knowledge transfer/training of new employees. This only extends the workforce temporarily, and cannot be used as a long term plan. Several strategies should be investigated in order to be prepared for the changing labor environment. The main "attractors" of a water utility include the salary and benefits, but other attractors should be identified to more effectively engage the younger generation. Studies indicate that the top three attractors to a position for current students and young professionals are work that enables learning and growth, work that is enjoyable, and work that is personally stimulating. It may also be beneficial to brand the Utility by passively advertising the attractors of the organization. A method to broaden the pool of potential applicants could be to develop relationships with high schools and universities in order to broaden and deepen applicant pools- It is important that the City develop a viable workforce strategy as a key component of its long term strategic business planning in order to ensure a sustainable workplace in a dynamic labor environment. The City should also be investing time and money into staff training to ensure that knowledge is easily transferred within the organization. According to the AWWA Peer Review Report of 2005, the City should decide if it is best to staff all (or near all) needs, or to staff for a base level and employ contractors, consultants, and others for needs above the established base. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 2-36 3 Water Quality Regulations and Goals 3.1 Water Quality Regulations U. S. drinking water standards have developed and expanded over the past 100 years as knowledge of the health effects of contaminants has increased and the treatment technology to control contaminants has improved. The principal driving force behind development of drinking water standards and regulations is protection of public health. This section provides an overview of past, present and future drinking water regulations with emphasis on their applicability to the City of Boulder as a provider of treated water to the public. A historical discussion of treatment regulations in the United States that date up to the 1996 Amendments to the Safe Drinking Water Act are briefly summarized in Table 5-7. Afterwards this section focuses on the 1996 SDWA Amendments onwards and how they apply to the City of Boulder. Table 5-7 is a chronological progression of major water quality regulations in the United States up until 1996_ City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-1 Table 5-7: Historical Regulations 1893 through 1996 Date Regulation Purpose 1893 Quarantine Act (U.S. The surgeon general of the U.S. Public Health Service (USPHS) was empowered Statutes 1893 Launch of review of 1913 drinking water Realization that "the most sanitary drinking water cups would be of no value if the water placed in them was unsafe" concerns First Federal Drinking "Treasury Standards" were implemented by USPHS, which was part of the US Treasury Department. Included a 100/cc 1914 (100 organisms/mL) limit for total bacterial plate count. Further, they stipulated that not more than one of five 10/cc Water Standards onions of each sample examined could contain Escherichia coli E. coil 1925 USPHS 1925 1 coliform per 100 mL and standards for lead, copper, zinc, and excessive soluble mineral substances Regulations 1941 USPHS formed Advisory committee reviewed the 1925 standards advisory committee New initiatives, including: • Samples for bacteriological examination obtained from points in the distribution system, a minimum number of bacteriological samples for examination each month was established, and the laboratories and procedures used in making these examinations became subject to state or federal inspection at any time. 1942 USPHS 1943 . Maximum permissible concentrations were established for lead, fluoride, arsenic, and selenium. Salts of barium, hexavalent chromium, heavy metals, or other substances having deleterious physiological effects were not allowed in the water system. • Maximum concentrations, not to be exceeded where more suitable alternative water sources were available, were set for copper, iron plus manganese, magnesium, zinc, chloride, sulfate, phenolic compounds, total solids, and alkalinity. 1962 1962 federal drinking 28 constituents, including mandatory limits for health-related chemical and biological impurities and recommended limits water standards for impurities affecting appearance, taste, and odor. Accepted b all 50 states, but were limited in enforcement. Community Water Survey of 969 public water systems, found that 41 % did not meet 1962 guidelines. Study found that several million people 1970 Supply Study (CWSS) were being supplied water of an inadequate quality and that 360,000 people were being supplied potentially dangerous drinking water. 1973 General Accounting 446 community water systems tested, only 60 complied with USPHS standards. Office GAO Report • SDWA became the principal law governing drinking water safety in the United States. Required for all public water Safe Drinking Water systems and made the standards legally binding. Established National Interim Primary Drinking Water Regulations December 16,1974 Act (SDWA) (NIPDWRs). (Public Law 93-523) • These regulations established maximum contaminant levels (MCLs) for 10 inorganic chemicals, six organic chemicals, two radioactive contaminants, turbidity, and coliform organisms. The interim rules were amended several times before the first primary drinking water regulation was issued. SDWA Amendments of Revisions of the National Academy of Sciences study, reflecting new information on microorganisms, particulate matter, 1977 1977, Public Law 95- inorganic solutes, and radionuclides 190 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-2 Date Regulation Purpose 1979 Amendments MCL for total trihalomethane TTHM compounds was added in 1979 SDWA Amendments of 1979 1979, Public Law 96- Reauthorization of the SDWA, including a 3 year extension of the authorizations 63 SDWA Amendments of Minor amendments including exemption extensions, allowed alternative procedures for underground injection control 1980 1980, Public Law 96- program, limited grant to states that have not assumed primary enforcement, provided grants to systems that demonstrate 502 new or improved methods for meeting more stringent standards 1986 Fluoride revision MCL for fluoride was revised in April 1986 • Established Phase I, II, Ilb, and V rules regulating 69 contaminants over a five-year period. In each rule, USEPA set limits on the contaminants, prescribed the schedule under which water systems must test for the presence of the contaminants, and described the treatments which systems may use to remove a detected contaminant. • For each contaminant, USEPA set a health goal, or Maximum Contaminant Level Goal (MCLG). This is the level at which a person could drink two liters of water containing the contaminant every day for 70 years without suffering any SDWA Amendments of ill effects. This goal was not a legal limit with which water systems must comply; but based solely on human health 1986 1986,Public Law 99- risk. For known cancer-causing agents (carcinogens), USEPA set the MCLG at zero, under the assumption that any 339 exposure to the chemical could present a cancer risk. • The rules also set a legal limit, or Maximum Contaminant Level, for each contaminant. USEPA set legal limits as close to the health based MCLG as possible, keeping in mind the technical and financial barriers that existed. Except for contaminants regulated as carcinogens, most legal limits and health goals are the same. Even when they are less strict than the health goals, the legal limits set provided substantial public health protection. • Along with their long-term effects, nitrate and nitrite were determined to be acute health risks for infants, meaning that the could cause immediate health problems even when consumed in tin doses. Limited exposure to eight Volatile Organic Chemicals (VOCs) that industries use in the manufacture of rubber, pesticides, 8 July 1987 Phase I Rule deodorants, solvents, plastics, and other chemicals and could potentially be in tap water. The rule required water systems to monitor and, if levels exceed legal limits, take corrective action to ensure that consumers receive water that does not contain harmful levels of the chemicals Lead Contamination Amended the SDWA to direct the USEPA to consider drinking water coolers with lead-lined tanks as imminently hazardous 31 Oct 1988 Control Act, Public Law consumer products which must be repaired, replaced, recalled, or refunded by their manufacturers and importers within 100-572 one year of this Act's enactment. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-3 Date Regulation Purpose • The Rule set both health goals (MCLGs) and legal limits (MCLs) for total coliform levels as an indicator organism in drinking water. The rule also detailed the type and frequency of testing that water systems must perform. • For water systems which collect at least 40 samples per month, if no more than 5.0 percent of the samples collected during the month were total coliform positive, the system was considered to be in compliance. 29 June 1989 Total Coliform Rule • Under the Rule, if a sample tests positive for coliforms, the system must collect a set of repeat samples within 24 hours. When a routine or repeat sample tests positive for total coliforms, it must also be analyzed for fecal coliforms and E. soli, which are coliforms directly associated with fresh feces. If either fecal or E. coli bacteria are present, it signifies an acute MCL violation. Rapid state and public notification by electronic media (TV or radio) is required within 72 hours because it represents a direct health risk. Under the coliform rule, states are allowed to disregard speciated coliform ositive tests that are not of fecal origin. • The Rule was established to prevent waterborne diseases caused by viruses, Legionelia, and Giardia lamblia. The rule requires that water systems filter and disinfect water from surface water sources to reduce the occurrence of unsafe levels of these microbes. • Filter systems are required to maintain a minimum disinfection residual of 0.2 mglL for water entering the distribution system. A detectable disinfectant residual must be maintained within the distribution system for a minimum of 95 percent of all samples analyzed on a monthly basis. Where no residual is detected, and a heterotrophic plate count (HPC) analysis indicates less than 500 colonies per ml, the sample is considered acceptable. Sampling frequencies and locations must be the same as required by the Coliform Rule. • In the Rule, filtration systems are required to maintain 99.9% (3-log) removal or inactivation for Giardia cysts and 29 June 1989 Surface Water 99.99% (4-log) removal for enteric viruses. Conventional granular media filtration can remove a high percentage of Treatment Rule Giardia cysts and viruses. Filtration can achieve 99.5% (2.5-log) removal of Giardia cysts and 99% (2-log) removal of viruses. To achieve the minimum required 99.9% (3-log) cyst and 99.99% (4-log) virus removal or inactivation criteria, the disinfection system must provide a minimum additional 0.5-log inactivation of cysts and 2-log inactivation of viruses. Virus inactivation in excess of a 4-log reduction is typically achieved when conditions for 3-log removal or inactivation of Giardia cysts are maintained. USEPA recommends specific minimum Giardia cyst removal ranging from 3-log to 5-log (October, 1990), depending upon the degree of cyst contamination in the source water. To assist in monitoring the effectiveness in the filtration process, turbidity (a measurement of water clarity) is monitored at 4-hour intervals. The combined filter effluent turbidity is not to exceed 5 nephelometric turbidity units (NTU) as a maximum and 0.5 NTU at the 95th percentile for all measurements taken during any month, based on monitoring every four hours. Legal limits on 38 contaminants were updated or created with these rules, many were frequently-applied agricultural 30 January and 1 July chemicals while others are more obscure industrial intermediate. For 36 of the 38 contaminants that the Phase II and Ilb 1991 Phase II and Ilb Rules rules address, USEPA set both health goals and legal limits. The other two contaminants that USEPA regulated through the rules, Acrylamide and Epichlorohydrin, are chemicals that some water systems add during the water treatment process. The rules limit the amount of these chemicals that systems may add to water during the treatment process. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-4 Date Regulation Purpose • USEPA set health goals (MCLGs) and action levels for lead and copper. All community public water systems have been required to monitor and, if necessary, control the amount of lead and copper in the potable water system. Lead and copper is monitored at user fixtures within the distribution system. Based on first-draw samples, lead and copper concentrations must be less than 0.015 mg/L and 1.3 mg/L in 90 percent of the samples, respectively. • When a water system exceeds either action level, it must also assess its source water. In most cases, there will be 7 June 1991 Lead and Copper Rule little or none of either contaminant in the source water and no treatment will be necessary. When there are high levels in the source water, treatment of that water, in conjunction with corrosion control, further lessens the chance that consumers will have elevated levels of lead and copper at the tap. Monitoring data and corrosion control study results must be submitted to the state, which then approves the required treatment. • The rule also requires systems that exceed the lead action level to educate the affected public about reducing its lead intake. Finally, a system which continues to exceed the lead action level after completing corrosion control and source water treatments may have to replace some of its lead water mains. The Phase V Rule set standards for 23 more contaminants including inorganic chemicals such as cyanide that are present 17 July 1992 Phase V Rule naturally in some water, though only at trace levels. Industrial activity accounts for the potentially harmful levels of these contaminants in drinking water. Other Phase V contaminants are pesticides. These chemicals enter water supplies through run-off from fields where farmers have applied them orb leaching through the soil into round water. To support the Microbial-DBP rulemaking process, it required large public water systems serving at least 100,000 people to monitor and collect data on microbial contaminants, disinfectants and DBPs for 18 months. Monitoring programs began 14 May 1996 Information Collection in July 1997 and were completed by December 1998. The data provided USEPA with information about disinfection Rule byproducts, disease-causing microorganisms, including Cryptosporidium, and engineering data to control these contaminants. This information was used in part to create the final Enhanced Surface Water Treatment Rule and the Stage 2 Disinfectants/Disinfection Byproducts Rule. The City of Boulder participated in the ICR at the BWTF from 7/97 to 12/98. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-5 The rules of the SDWA apply to all public water systems. The City of Boulder is regulated because it owns and operates a public water system. Public water systems are further broken down into different types. Rules apply differently based on the size of the system and classification of the water source. Monitoring and reporting requirements vary significantly depending upon the size of a system. With a service area population of approximately 113,000 people the City of Boulder is classified as a very large water system. The regulations also differ depending on whether a system relies on surface water, groundwater or a combination of both- The City of Boulder uses surface water exclusively. For clarity, the remainder of this section will focus on those provisions of the regulations that apply to Boulder as a very large system using exclusively surface water. States and Indian Tribes are given primary enforcement responsibility "primacy." This allows the Colorado Department of Public Health and Environment's (CDPHE's) Water Quality Control Division to enforce the federal rules as a minimum and the ability to enforce more strict requirements, if necessary. On August 6, 1996, the President signed new SDWA amendments into law as Public Law 104-182. These amendments made sweeping changes to the existing SDWA, created several new programs, and included a total authorization of more than $12 billion in federal funds for various drinking water programs and activities from fiscal year (FY) 1997 through FY2003. The 1996 SDWA Amendments establish an emphasis on preventing contamination problems through source water protection and enhanced water system management. This emphasis transformed the previous law, with its largely, after-the-fact and regulatory focus, into a statute that provides for the sustainable use of water by our nation's public water systems and their customers. Inherent in the act is closer interaction with the states in creating and focusing prevention programs, and helping water systems improve operations and avoid contamination problems. In addition, the Amendments specify that the public be provided with or given access to data collected, analyses done or implementation strategies developed under new SDWA programs. These consumer information provisions provide for public involvement in safe drinking water, founded on the idea that the understanding and support of the public will be vital to address and prevent the growing threats to drinking water quality in the years ahead. Key provisions of the 1996 amendments include the following. • Consumer Confidence Reports • Source Water Protection • Capacity Development • Operator Certification • New risk-based contaminant selection • Cost-benefit analysis and research for new standards • Unregulated Contaminant Monitoring Regulation • Drinking Water State Revolving Fund • Rules: > Radon, Arsenic, Disinfection Byproducts (DBP)ICryptosporidium, Sulfate A decade of experience under the 1986 SDWA revealed several areas where responsibly exercised flexibility supported by sound scientific evidence and a better prioritization of effort could improve protection of public health compared to the relatively inflexible approach of the 1986 statute. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-6 New Risk-Based Contaminant Selection: The requirement that USEPA regulate an additional 25 contaminants every three years was eliminated. Instead, USEPA was given the flexibility to decide whether or not to regulate a contaminant after completing a required review of at least five contaminants every five years. USEPA must use three criteria to determine whether or not to regulate a contaminant: that the contaminant adversely affects human health; it is known to or is substantially likely to occur in public water systems with a frequency and at concentrations high enough to be of public health concern; and regulation of the contaminant presents a meaningful opportunity for health risk reduction. [102/1412(b)(1)] Cost-Benefit Analysis and Research for New Standards: For all future drinking water standards, USEPA is to conduct a thorough cost-benefit analysis and provide comprehensive, informative, and understandable information to the public. USEPA is also required to use the "best available, peer- reviewed science and supporting studies" in carrying out actions within the standard setting section "to the degree that an Agency action is based on science." [103/1412(b)(3)] Small System Technologies, Variances, and Exemptions: A fundamental problem with the previous law was that, in setting standards based on technology that large systems could afford, it did not recognize the often-different economics of small systems. The new law contains multiple remedies. First, as part of a new drinking water standard, USEPA is to identify technologies that comply with the standard and are specifically affordable for each of three groups of smaller systems [105/1412(b)(4)(E)]. Second, where such technologies do not exist for a certain group of smaller systems or quality of source water, a "variance" technology must be identified that need not meet the standard but must provide the maximum protection affordable for such groups of smaller systems and source waters. [111/1412(b)(15)] Within two years, USEPA must identify affordable compliance and, where appropriate, variance technologies for existing regulations, and issue regulations for small system variances. Compliance Time Frames: The Amendments extend to three years the previous 18-month deadline for systems to comply with new regulations, unless USEPA determines an earlier date is "practicable." USEPA or States (for individual systems) may give an additional two years if necessary for capital improvements. [108/1412(b)(10)] Monitoring Reforms: States may grant "interim monitoring relief' to systems under 10,000 (exempting them from additional quarterly monitoring) if monitoring done at the time of "greatest vulnerability to the contaminant" fails to detect it, and the State finds that further monitoring is unlikely to detect it. This relief may not cover any microbiological contaminants (or their indicators), disinfectants, or disinfection or corrosion byproducts [125(b)/1418(a)]. Enforcement: The Amendments streamline processes for administrative compliance orders and penalties up to $5,000 that raise the administrative and emergency penalty caps, and make enforceable many SDWA provisions and requirements imposed under them by USEPA or primacy States, and give up to a two-year enforcement moratorium for violations being remedied by a specific plan to consolidate with another system. States must also adopt administrative penalty authority for primacy. These measures will facilitate more effective enforcement, encouraging compliance while keeping safeguards for systems [113/1414]. The creation of a Drinking Water State Revolving Fund (SRF), to assist communities in installing and upgrading safe drinking water treatment facilities, is among the new statute's most dramatic departures from the past, and among the most important changes in the nation's drinking water program since passage of the original SDWA in 1974. The President proposed the SRF in 1993 to advance the same City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-7 kind of national commitment to safe drinking water as America has made to wastewater treatment and clean water- Drinking Water State Revolving Fund: The SRF was authorized at $599 million for FY1994, and $1 billion annually thereafter through FY2003. The full span of this authorization is meaningful because the law permits appropriation in future years of any funds authorized but not appropriated in prior years. Funds are allotted to all primacy through FY1997 based on the current formula for Public Water System Supervision grants, and thereafter based on the results of the most recent SRF needs survey. The fiscal year 2009 appropriation for the SRF program was $829,029,000. SRF Grants to States for Prevention Programs and Projects: One of the most notable features of the law is the authorization to States to use SRF funds for the new prevention programs. Up to 10 percent of their capitalization grants may be used for source water protection, capacity development, and operator certification programs, as well as for the State's overall drinking water program. The 1996 SDWA Amendments required the City of Boulder to prevent contamination problems through source water protection and enhanced water system management. It also required the City to be more transparent in their reporting and notifications. 3.1.3.1 Interim Enhanced Surface Water Treatment Rule (IESWTR) Over time, improved analytical techniques identified specific microbial pathogens, such as Cryptosporidium, which are highly resistant to traditional disinfection practices as well as being difficult to remove through conventional treatment processes. In 1993, Cryptosporidium caused 400,000 people in Milwaukee to experience intestinal illness. More than 4,000 were hospitalized, and at least 50 deaths have been attributed to the disease. There have also been cryptosporidiosis outbreaks in Nevada, Oregon, and Georgia. The Interim Enhanced Surface Water Treatment Rule (IESWTR) (published 16 December 1998/effective December 2001) amended the 1989 SWTR to strengthen microbial protection, including provisions specifically to address Cryptosporidium, and to address risk trade-offs with disinfection byproducts. The IESWTR applied to surface water and groundwater under the direct influence of surface water systems serving over 10,000 people. The rule included the requirement for at least a 2-log removal of Cryptosporidium, credits for Cryptosporidium removal based on properly functioning filters, strict filter effluent turbidity performance requirements, and clearly defined reporting requirements. r~ The Long Term 2 Enhanced Surface Water Treatment Rule (adopted in 2006) superseded the IESWTR. The effect these rules had on the City of Boulder is discussed later in this chapter. 3.1.3.2 Stage 1 D/DBPR For some time, it has been a major challenge for water suppliers to balance the risks from microbial pathogens and disinfection byproducts. It is important to provide protection from these microbial pathogens while simultaneously ensuring decreasing health risks to the population from DBPs. The Stage 1 D/DBRP (published 16 December 1998/effective 1 December 2001) attempted to reduce the levels of exposure to disinfectants and disinfection byproducts in drinking water supplies. The Stage 1 D/DBPR updated and superseded the 1979 regulations for total trihalomethanes. In addition, it set limits for exposure to three disinfectants and many disinfection byproducts. The rule provided public health City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-8 protection from exposure to haloacetic acids, chlorite (a major chlorine dioxide byproduct) and bromate (a major ozone byproduct). The rule established maximum residual disinfectant level goals (MRDLGs) and maximum residual disinfectant levels (MRDLs) for three chemical disinfectants - chlorine, chloramine and chlorine dioxide. Table 5-8 shows the maximum contaminant level goals (MCLGs) and maximum contaminant levels (MCLs) for total trihalomethanes, haloacetic acids, chlorite and bromate. Table 5-8: Stage 1 DjDBFRs Disinfectant Residual MRDLG m /L MRDL m /L Compliance Based On Chlorine 4 as CI2 4.0 as CI2 Annual Average Chloramine 4 as CI2 4.0 as CI2 Annual Average Chlorine Dioxide 0.8 as C102 0.8 as C102 Dail Samples DBPs MCLG m /L MCL m /L Compliance Based On Total trihalomethanes TTHM l NIA Chloroform N/A3 Bromodichloromethane 0 0.080 Annual Average Dibromochloromethane 0.06 Bromoform 0 Haloacetic acids five haloacetic acids HAAS 2 N/A Dichloroacetic acid 0 0.060 Annual Average Trichloroacetic acid 0.3 Chlorite 0.8 1.0 Monthly Average Bromate 0 0.010 Annual Average N/A - Not applicable because there are individual MCLGs for TTHMs or HAASS, unless otherwise noted. 'Total trihalomethanes is the sum of the concentrations of chloroform, bromodichloromethane, dibromochloromethane, and bromoform. 2Haloacetic acids (five) are the sum of the concentrations of mono-, di-, and trichloroacetic acids and mono- and dibromoacetic acids. The USEPA removed the value of zero for the MCLG for Chloroform from its National Primary Drinking Water Regulations, effective May 30, 2000, in accordance with an order of the U.S. Court of Appeals for the District of Columbia Circuit. Note: Stage 1 D/DBPR was superseded b Stage 2 D/DBPR, which Water systems that use surface water and use conventional filtration treatment are required to remove specified percentages of organic materials, measured as total organic carbon (TOC) that may react with disinfectants to form DBPs. The level of removal of TOC is specified in Table 5-9 and the routine monitoring requirements are included in Table 5-10. Source Water Alkalinity m /L as CaC03' Source Water TOC m /L 0-60 > 60-120 > 1202 >2.0-4.0 35.0% 25.0% 15.0% >4.0-8.0 45.0% 35.0% 25.0% >8.0 50.0% 40.0% 30.0% 'Systems meeting at least one of the alternative compliance criteria in the rule are not required to meet the removals in this table. 2S stems practicing softening must meet the TOC removal requirements in the last column to the right. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-9 Table 5-10: Routine Monitoring Re-Air- mertc for Co-vertional Filtratio; tment Plants Large Surface Water System with Requirement Location for sampling Conventional Filtration TOC and Alkalinity Source Water (TOC and Alkalinity sample must be 1 sample/month/plant at same location and time 25% in distribution system at maximum residence TTHMs and HAAS time, 75% at distribution system representative 4/plant/quarter locations Chlorine and Same points as total coliform in TCR Same times as total coliform in TCR Chloramines Compliance with the Stage 1 D/DBPR was required at the state level by December 17, 2001. Reduced monitoring limits are available if the source water annual average TOC, before any treatment, is less than 4.0 mg/L and then annual average of TTHM is less than 0.040 mg/L, and the annual average of HAAS is less than 0.030 mg/L (1996 SDWA Programs). The Long Term 2 Enhanced Surface Water Treatment Rule (adopted in 2006) superseded the IESWTR. The effect these rules had on the City of Boulder is discussed later in this chapter. 3.1.3.3 Consumer Confidence Reports (CCRs) The Consumer Confidence Report rule was created by the 1996 reauthorization of the Safe Drinking Water Act. The Environmental Protection Agency published the final regulation on August 19, 1998 (Federal Register, Volume 63, and Number 160). The rule requires community water systems to provide annual reports to their customers on the quality of their drinking water. The Consumer Confidence Reports inform water system customers about the quality, safety, and reliability of their drinking water. All water utilities are required to provide the reports by July 1 of each year. The CCR does not replace annual monitoring and reporting requirements of the SDWA_ Water utilities must deliver the report directly to each customer by hand or through the regular mail service. Consumer confidence reports summarize information that water systems already collect to comply with current regulations. The federal rule has specific requirements for mandatory language and reporting detected contaminants. The required information for the CCR is summarized below. • Name and location of water source(s) • Type of water (groundwater, surface water, imported water) • Concentrations of regulated contaminants detected in the water • Concentrations of unregulated (monitoring only) contaminants detected in the water • Concentrations of disinfection byproducts • Concentrations of microbial contaminants • Allowable Maximum Contaminant Levels for each contaminant monitored • Health effects of contaminants exceeding any allowable MCL • Probable sources of any contaminants • Violations of monitoring, reporting, treatment, or record keeping requirements • Public involvement opportunities • Sources of additional information City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-10 Utilities may include additional information to explain or help customers interpret the CCR data. r--~ The City of Boulder is required to produce consumer confidence reports annually to the citizens of Boulder. The most recent 2010 report is available online on the City's website: http://www,bouldercolorado.gov/files/Utilities/Water%20QualitV/Final For Posting On C OB Website.pdf 3.1.3.4 Source Water Protection Every state with primacy is required to develop a Source Water Assessment and Protection Program (SWAP) as a means of protecting water used for public drinking water supplies. SWAP calls for the states to conduct an assessment, coordinated with existing information and programs, to determine the vulnerability of drinking water sources within their boundaries. The concept was not new, as it had been employed ten years before with the wellhead protection program, a preventive approach to protecting ground water sources of drinking water. Source water expands the concept to include surface water sources as well. SWAP is a two-phased process; assessment and protection. The assessment phase must include four elements: Involvement of the public in the design and implementation of the source water assessments; delineation of the source water assessment areas (SWAAs) for each public water system (PWS); an inventory of significant potential sources of contamination (PSOCs) within the SWAA; and a determination of the susceptibility of the PWS intake or well to the inventoried contaminants. The protection phase utilizes the information obtained from the assessment phase and encourages the public water providers to employ measures within the SWAA that will help ensure the long term integrity of the water source. A SWAA becomes a source water protection area (SWPA) with the development of a protection plan and implementation of protection measures. SWAP in Colorado is organized by watershed. These are subdivided into hydrologic units and sub-units within the SWAAs that are defined. Organization of SWAP by watershed coincides with federal and state policies to manage water quality within this context. The Safe Drinking Water Act specifies that the following tasks must be undertaken to adequately assess a PWS' source water: • Delineate the area or zone through or over which contaminants, if present, are likely to migrate and reach the drinking water well or surface water intake. • Inventory PSOCs. Assemble data on regulated and unregulated PSOCs along with information on the structure of the wells and intakes, and the hydrogeology within the delineated SWAA. • Analyze the susceptibility of the drinking water source to the contaminants identified. • Rate the PWS as having high, moderate, or low susceptibility to the type of contaminants or contaminant sources identified. ` N The CDPHE Water Quality Control Division performed the SWAP for Boulder as well as other Colorado systems based on existing databases. This information provided during this protection phase is voluntary. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-11 3.1.3.5 Capacity Development The 1996 Amendments create a program to build nationally on the demonstrated success of several States in strengthening the managerial, technical and financial capacity of water systems to reliably deliver safe drinking water. State programs must have two main components: (1) legal authority to ensure that new water systems have sufficient technical, managerial, and financial capacity to meet drinking water standards; and (2) a strategy to identify and assist existing water systems needing improvements in managerial, technical, or financial capacity or aid to comply with standards. These amendments to the 1996 SDWA impacted on the State of Colorado's program more than the City of Boulder. 3.1.3.6 Operator Certification Ensuring the knowledge and skills of public water system operators is widely considered one of the most important, cost-effective means to strengthen drinking water safety. To that end, the Amendments require all States to carry out a program of operator certification. Each State must either: (a) implement a program that meets the guidelines established by USEPA, or (b) enforce an existing State program, provided it is substantially equivalent to or meets the overall public health objectives of USEPA's guidelines. The City of Boulder has 2 Class A and 1 Class B operators at the BWTF and 2 Class A and 1 Class D operator at the BRWTF. These certified operators along with other operators, mechanics, and process optimization specialists ensure that the water quality from the two treatment facilities meets and exceeds the requirements for water treatment set by CDPHE. 3.1.3.7 Public Notification Rule In 2000 the USEPA Public Notification (PN) Rule set new strict requirements on the form, manner, content, and frequency of public notices. The notices must contain: • A description of the violation that occurred, including the potential health effects • The population at risk and if alternate water supplies need to be used • What the water system is doing to correct the problem • Actions consumers can take • When the violation occurred and when the system expects it to be resolved • How to contact the water system for more information • Language encouraging broader distribution of the notice The regulation divides the public notice into three tiers: Tier 1, for violations and situations with significant potential to have serious adverse effects on human health as a result of short-term exposure. Notice is required within 24 hours of the violation. Tier 2, for other violations and situations with potential to have serious, but not immediate, adverse effects on human health. Notice is required within 30 days, or as soon as possible, with extension of up to three months for resolved violations at the discretion of the State or primacy agency. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-12 Tier 3, for all other violations and situations not included in Tier 1 and Tier 2. Notice is required within 12 months of the violation, and may be part of a single annual report, including in some cases the annual CCR already required by EPA. The PN Rule forces the City of Boulder to inform the community of any violation in treatment quality via the three tiers listed above. 3.1.3.8 Unregulated Contaminant Monitoring Regulation (UCMR) The first cycle of the Unregulated Contaminant Monitoring Regulation (UCMR 1) (published 17 September 99/effective 1 January 2001) is used to support the "sound science" approach to future drinking water regulations. The requirements for unregulated contaminant monitoring were first established by the 1986 SDWA Amendments. Since its inception in 1988, the UCM program has collected occurrence data to help USEPA determine which contaminants USEPA should regulate based on contaminant concentrations in PWSs and the contaminants' adverse health effects levels. Data generated by this rule will be used to: (1) evaluate and prioritize contaminants on the Contaminant Candidate List (CCL) and refine the CCL; (2) support the Administrator's determination of whether to regulate a contaminant under the drinking water program; and, (3) support the development of drinking water regulations. The program includes: (1) a new list of contaminants; (2) a representative sample of PWSs serving 10,000 or fewer person to monitor; (3) placement of the monitoring data in the National Drinking Water Contaminant Occurrence Database (NCOD), and; (4) notification of consumers that the monitoring results are available. UCMR 1 covered the period 2001 through 2005 and is currently superseded by UCMR 2 which covers the period 2007 through 2011. UCMR 2 (effective on February 5, 2007) is the final rule which describes the design for the second UCMR cycle. Under UCMR 2, USEPA requires the monitoring of 25 chemicals using five different analytical methods. UCMR 2 monitoring will occur during 2008 through 2010.' The most recent CCL (CCL3) is listed later in this section. 3.1.3.9 Arsenic On January 22, 2001 the USEPA adopted a new arsenic MCL of 10 ppb, which replaced the previous standard of 50 ppb. The new Arsenic Rule became effective on February 22, 2002 and water treatment systems were required to comply with the new rule by January 23, 2006. The MCLG for arsenic is 0 ppb. The City of Boulder monitors arsenic at the entry point to the distribution system once annually. The City also voluntarily monitors arsenic monthly at the entry point to each WTF, which is not required by CDPHE. http://www.epa.gov/fedrgstr/EPA-WATER/2007/January/Day-04/w22123.htm City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-13 3.1.3.10 Stage 2 D/DBPR The Stage 2 D/DBPR was implemented in 2006 and revises the original Stage 1 D/DBPR. The rule only applies to utilities serving more than 10,000 consumers. The following presents a general overview of the rule: • Initial Distribution System Evaluation (IDSE) - Surface water systems and groundwater systems were required to conduct one year of monitoring at sample locations that are separate from the current DBP compliance sample locations. The sample locations were determined based on the type of distribution system residual maintained by the system. • The results of the IDSE were then used to determine those sites in the distribution system that have the highest DBPs and to select from these sites four new DBP compliance monitoring locations per plant. • Compliance with the Stage 2 D/DBPR is determined using a Locational Running Annual Averages (LRAA), rather than system-wide averages, using the same MCL's as the Stage 1 D/DBPR. This means that the results from DBP sampling are no longer averaged across the entire distribution system. Instead, the results of sampling are averaged each quarter at each sampling site and the running annual average of the results at each location must meet the MCL's. Best available technology for meeting the Stage 2 MCLs, as defined by EPA, is enhanced coagulation (or softening), and groundwater activated carbon (GAC) adsorption with empty bed contact times of 10 or 20 minutes. The City collects data on TOC removal and alkalinity, disinfection byproducts (TTHM, HAAS), Chlorine MRDL, and Chlorine at various points in the raw water and/or distribution system. A detailed discussion of the City's regulatory compliance as related to the Stage 2/DBPR is included in Section 5.1.3 Regulatory Compliance. t The BWTF complies with an alternative compliance criteria of having the treated water TOC level being less than 2 mg/L. The City of Boulder has had to use an alternative compliance method for TOC at the BRWTF because the standard TOC was not always meeting the requirements. The Specific UV-absorption (SUVA) calculation is used for the BRWTF, which is less than or equal to 2 L/mg-m.. Further details on how the BRWTF is meeting the requirements using a carbonic acid system is described in Section 5.1.2. 3.1.3.11 Long Term Enhanced Surface Water Treatment Rule (LT2ESWTR) The LT2ESWTR was adopted in 2006 and applies to surface water and groundwater under the direct influence of surface water sources, it provides new information and supersedes the IESWTR. The objective of the rule is to reduce the risk associated with Cryptosporidium and other microbial pathogens in drinking water and address risk-risk tradeoffs with the control of disinfection byproducts. Sampling of raw water sources for Cryptosporidium is required under the LT2ESWTR. The following presents a general overview of the LT2ESWTR: • Surface water systems serving greater than 10,000 people were required to conduct monitoring for Cryptosporidium (and E. coli) for 24 months to determine the source water concentration of Cryptosporidium for a given system. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-14 • Each utility determined a bin classification based on the Cryptosporidium sample results- Bins are calculated by averaging individual sample results from one or more years of monitoring. Specific procedures vary depending on the frequency and duration of monitoring. Treatment bins are shown in Table 5-11. If the level of Cryptosporidium requires additional treatment beyond conventional filtration, a number of methods of meeting the treatment requirement are available, including membrane filtration and disinfection with ultraviolet (UV) light_ USEF A Classification Table a i "water Systems Und Average For Public Water Systems Cryptosporidium Additional Treatment Requirements for that Are... Bin Concentration Systems with Conventional Treatment 1 Crypto < 0.075 oocysts/L No action 1.0-log treatment (0.5-log removal + 0.5-log 2 0.0751L < Crypto < 1.01L inactivation or 1.0 log or greater from microbial toolbox) Required to monitor for 2-log treatment (with at least 1.0 log inactivation - Cryptosporidium 3 1.0 < Crypto < 10/1- e.g., UV, 03, C102, membranes, bag filters or bank filtration) 3-log treatment (with at least 1.0 log inactivation - 4 Crypto > 3.0/L e.g., UV, 03, C102, membranes, bag filters or bank filtration) Serving fewer than 10,000 people and NOT required to 1 N/A No action monitor for Cryptosporidium 'Filtered PWSs serving fewer than 10,000 people are not required to monitor for Cryptosporidium if they monitor for E. coli and demonstrate a mean concentration of E. coli less than or equal to 10/100 mL for lake/reservoir sources or 50/100 mL for flowing stream sources or do not exceed an alternative State-approved indicator trigger (see section IV.A.1). The SWTR requires the City of Boulder to report the results of a Microscopic Particulate Analysis (MPA) from samples taken on the raw water and the combined filter effluent of both facilities annually (with rotating quarters - e.g., 2010 was in the fourth quarter of the year). The City of Boulder conducted the required monitoring programs for the BRWTF from January 2001 - October 2004 with follow-up sampling in June 2006 and for the BWTF from January 2001 - October 2004 with follow-up sampling in October 2008. The City of Boulder is required to monitor for Cryptosporidium and falls within Bin Classification 1. 3.1.3.12 Filter Backwash Recycling Rule (FBRR) On June 8, 2001, USEPA published the final Filter Backwash Recycling Rule in the Federal Register. The following presents a summary of the FBRR: 1. Applies to surface water and groundwater under the direct influence of surface water systems that utilize conventional or direct filtration (as defined in the Code of Federal Regulations) that City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-15 practice recycle of filter backwash water, thickener supernatant, or liquids from dewatering processes. 2. By December 8, 2003, systems that recycle filter backwash water, thickener supernatant, or liquids from dewatering processes must have notified the State of the following: (a) plant schematic showing origin of all flows that are recycled, hydraulic conveyance used to transport the flows and location where they are returned to treatment plant, (b) typical recycle flow in gallons per minute, (c) highest observed plant flow during the previous year, (d) design flow for the treatment plant in gallons per minutes, (e) State approved operating capacity for the treatment plant (if the State had made such a determination). 3. Any system that recycles (spent filter backwash water, thickener supernatant, or liquids from dewatering processes) must have returned flows through all processes of the system's existing conventional or direct filtration plant (or an alternate location approved by the State) by June 8, 2004. 4. If a system needed to make capital improvements to comply, these improvements must have been completed by June 8, 2006. 5. Systems must have recordkeeping requirements (to be reviewed during sanitary surveys) including (a) copy of notification and information submitted to the State as described above, (b) list of all recycle flows and frequency with which they are returned, (c) average and maximum backwash flow rate through filters, average and maximum duration of the filter backwash cycle, (d) typical filter run length and a written summary of how filter run length is determined, (e) if applicable, type of treatment provided for recycle flow, (f) information on physical dimensions of any equalization and/or treatment units, typical and maximum hydraulic loading rates, type of treatment chemicals, average dose and frequency of use, and frequency at which solids are removed, if applicable- The objective of the Filter Backwash Rule is to prevent the return of concentrated contaminants removed by filters. On June 8, 2001, USEPA published the final Filter Backwash Recycling (FBR) Rule in the Federal Register. The City of Boulder has records which comply with the requirements for this rule. 3.1.3.13 Radionuclides Rule EPA revised the radionuclide rule on December 7, 2000. The rule retained the existing MCLs for combined radium-226 and radium 228 of 5 pCi/I, gross alpha particle radioactivity of 15 pCi/l, and beta particle and photon emitters at 4 mrem/yr. The rule now regulates uranium with a MCL of 30 tag/l. MCLGs for all of the regulated radionuclides are zero. The City of Boulder monitors Uranium, Radium226,228, and Gross Alpha at the entry point into the distribution system every 9 years. The next monitoring will need to occur in 2011. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-16 3.1.4 Future Regulations 3.1.4.1 Contaminant Candidate List 3 (CCL3) In October 2009, USEPA published a final list of contaminants which may require regulation under the SDWA. This final Contaminant Candidate List 3 (CCL3) includes 104 chemicals of chemical groups and 12 microbiological contaminants which are known or anticipated to occur in public water systems. The list includes chemicals used in commerce, pesticides, waterborne pathogens, DBPs and biological toxins. The Agency evaluated approximately 7,500 chemicals and microbes and selected 116 candidates for the CCL3 that have the potential to present health risks through drinking water exposure. The CCL3 list is included below in Table 5-12. 3.1.4.2 Unregulated Contaminant Monitoring US Environmental Protection Agency recently outlined its plans to have certain utilities monitor for 30 contaminants under the third Unregulated Contaminant Monitoring Rule, (UCMR3). The City of Boulder will be part of this effort and will monitor 24 of the targeted contaminants in the CCL3. The City will be part of 4,800 utilities to start the third round of Assessment Monitoring in 2013 for 22 unregulated contaminants - including seven hormones; 1,4, dioxane; nine volatile organic compounds (VOCs); four metals; and chlorate. In addition the USEPA is considering a Screening Survey for six perfluorinated alkyl acids. This information was announced in April of 2010 and will be used by the EPA to make future regulatory determinations. 3.1.4.3 Revised Total Coliform Rule In 2007, USEPA decided to establish a committee under the Federal Advisory Committee Act. This charge to the Total Coliform Rule/Distribution System Advisory Committee (TCR/DSAC) was to develop an agreement in principle regarding recommendations to USEPA on revisions to the TCR and on what information about distributions is needed to better understand and address possible public health impacts from potential degradation of drinking water quality in distribution systems. On September 18, 2008, the TCRDSAC signed an Agreement in Principle that recommended revisions to the 1989 TCR. In 2010, the USEPA proposed revisions to the 1989 TCR. The 2010 proposed revisions to the TCR will: • require public water systems that are vulnerable to microbial contamination to identify and fix problems, and • establish criteria for systems to qualify for and stay on reduced monitoring, thereby providing incentives for improved water system operation. The City of Boulder currently monitors total coliform and chlorine by taking 120 samples monthly within the distribution system. This information is reported to CDPHE within 10 days after the month's end. The 2010 Revised TCR may allow the City to reduce the monitoring frequency, if the data continues to consistently meet the requirements. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-17 Table 5-12: Contaminant Candidate List 3 (CCL3) Chemical Contaminants Common Name - Registry Name 1,1,1,2-Tetrachloroethane Estrone RDX 1,1-Dichloroethane Ethinyl Estradiol (17-alpha Ethynyl Estradiol) sec- Butylbenzene 1,2,3-Trichloropropane Ethoprop Thiodicarb 1,3-Butadiene Ethylene glycol Thiophanate-methyl 1,3-Dinitrobenzene Ethylene oxide Toluene diisocyanate 1,4-Dioxane Ethylene thiourea Tribufos 17 alpha-Estradiol Fenamiphos Triethylamine 1-Butanol Formaldehyde Triphenyltin hydroxide (TPTH) 2-Methoxyethanol Germanium Strontium 2-Propen-1-ol Halon 1011 (bromochloromethane) Tebuconazole 3-Hydroxycarbofuran HCFC-22 Tebufenozide 4,4'-Methylenedianiline Hexane Tellurium Acephate Hydrazine Terbufos Acetaldehyde Mestranol Terbufos sulfone Acetamide Methamidophos Urethane Acetochlor Methanol Vanadium Acetochlor ethanesulfonic acid (ESA) Methyl bromide (Bromomethane) Vinclozolin Acetochlor oxanilic acid (OA) Methyl tert-butyl ether Ziram Acrolein Metolachlor Alachlor ethanesulfonic acid (ESA) Metolachlor ethanesulfonic acid(ESA) Microbial Contaminants Alachlor oxanilic acid (OA) Metolachlor oxanilic acid (OA) Adenovirus alpha-Hexachlorocyclohexane Molinate Caliciviruses Aniline Molybdenum Campylobacter jejuni Bensulide Nitrobenzene Enterovirus Benzyl chloride Nitroglycerin Escherichia soli (0157) Butylated hydroxyanisole N-Methyl-2-pyrrolidone Helicobacter pylori Captan N-nitrosodiethylamine (NDEA) Hepatitis A virus Chlorate N-Nitrosodimethylamine (NDMA) Legionella pneumophila Chloromethane (Methyl chloride) N-Nitroso-di-npropylamine (NDPA) Mycobacterium avium Clethodim N-Nitrosodiphenylamine Naegleria fowled Cobalt N-nitrosopyrrolidine (NPYR) Salmonella enteric Cumene hydroperoxide Norethindrone (19-Norethisterone) Shigella sonnei Cyanotoxins N-Propylbenzene Dicrotophos o-Toluidine Dimethipin Oxirane, methyl- Dimethoate Oxydemeton-methyl Disulfoton Oxyfluorfen Diuron Perchlorate Equilenin Perfluorooctane sulfonic acid (PFOS) Equilin Perfluorooctanoic acid (PFOA) Erythromycin Permethrin Estradiol (17-beta estradiol) Profenofos Estriol Quinoline City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-18 3.1.4.4 Revised Lead and Copper Rule The Lead and Copper Rule is on target to be revised in the spring of 2012, with finalization in 2014. Revisions are likely to include revisions to the current sample tiers, changes to lead service line replacement requirements, and sampling at schools and child care facilities. 3.1.4.5 Endocrine Disrupting Compounds and Pharmaceuticals and Personal Care Byproducts Another area of possible future regulatory activity is the regulation of endocrine disrupting compounds. Endocrine disrupting compounds (EDCs) are chemicals that interfere with the natural function of the endocrine system (glands and hormones) in both humans and animals. Growing evidence of harmful effects of EDCs on humans and other biota has captured the attention of the general public as to the seriousness of this issue. Potential health effects include lower sperm counts in men, earlier puberty, and increases in occurrences of reproductive organ cancer. Endocrine disrupting compounds are ubiquitous in the environment and can be found in both point and non-point sources. EDCs in drinking water may originate from 1) surface water, groundwater, or reservoir source water that was contaminated by point or non-point source pollution, 2) chlorinated or oxygenated compounds that are produced as byproducts during water treatment processes, and 3) contact with material in the water supply system. For humans, exposure to EDCs can occur through food, water, and air. Compounds classified as potential EDCs vary among regulatory and environmental organizations around the world. There is still a need for agreement on the specific effects that would be required to classify a substance as a potential endocrine disrupting compound. A complete listing of known EDC and PPCP compounds is lengthy and EPA's prohibitively costly plan to eventually test the full universe of 87,000 known chemicals for endocrine disrupter activity will further lengthen this list. Presently, the best approach is to focus on those compounds where analytical methodologies have been developed and survey work has demonstrated frequent occurrence. General categories of PPCPs detected with greatest frequency are included in Table 5-13. =s of F'PC. Fs Detected wiil_ requency in 6 =;ai USGS) Urbanized Stream; nce Survey, r Category Compounds Frequency Detected Steroids (fecal indicators) Coprostanol 86% Cholesterol 85% Insect Repellent DEET 75% Nonprescription Stimulant Caffeine 60% Nonprescription Nicotine Metabolite Cotinine 38% Nonprescription Stimulant Metabolite 1,7-dimethylxanthine 30% Fire Retardant Tri(2-chloroethyl)phosphate 58% Antimicrobial Household Disinfectant Triclosan 58% 4-Nonylphenol 52% Detergents 4-Nonylphenol monoethoxylate 46% 4-Octylphenol monoethoxylate 44% 4-Nonylphenol diethoxylate 38% Plasticizers Ethan ol-2-butoxy-phosphate 46% Polymer Ingredient Bisphenol-A 42% Antioxidants (food preservatives) 5-methyl-1 H-benzotriazole 33% Polyaromatic Hydrocarbon Fluoranthene (priority pollutant) 31% Pyrene (priority pollutant) 29% Antibiotics Trimethoprim 27% City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-19 Presently, there is no consensus on the use and validity of toxicity tests for the evaluation of the toxic hazard to humans from EDCs. Many challenges exist for EDC assessment. Some effects are demonstrable at very low dosage exposures; however, the levels of contamination known to cause effects are dramatically lower than current testing procedures are able to measure. Dose-response curves do not necessarily follow the classic assumption that as the dose increases so too does the effect. For some endocrine disrupting compounds, effects may disappear at higher levels, or become qualitatively different. Under other circumstances, there may be no threshold level below which there is no effect. Contaminant exposures take place in mixtures and these mixtures can interact additively, synergistically, or not at all. This means that toxicological tests conducted for most regulatory decisions must be repeated at environmentally relevant (i.e., much lower) levels. In the meantime, this means the USEPA, Food and Drug Administration, and industry are lacking in scientific guidance for regulatory decisions related to EDCs. In 2007, the Water Research Foundation implemented the Strategic Research Initiatives Program's "Distribution System Water Quality and EDC s/PPCPs in Drinking Water." This program will help to develop methods to detect and quantify these compounds in drinking water, assess the occurrence of these compounds, evaluate the toxicological relevance to human health, develop cost effective source control and treatment alternatives, and develop effective tools and strategies for outreach and communication with drinking water customers. (Water Research Foundation (2010) Endocrine Disrupting Compounds/Pharmaceuticals and Personal Care Products Strategic Research Initiative - Strategic In addition, nanoparticles (particles with a dimension of 100 nm or less) used in PPCPs have recently become a point of concern. Nanoparticles immediately adsorb onto the surface of some larger molecules. Nanoparticles have been used as a drug delivery mechanism to direct the drug to a specific location, sometimes a specific cell, in the body. Depending on the dose and solubility, these nanoparticles can either dissolve to impact living organisms as the chemical was designed, or others tend to accumulate in biological systems. There is a lot of research into these nanoparticles and their effect on health and the environment. Currently, there are no regulations specific to EDCs in the U.S., but the USEPA has designed an approach to select its first set of chemicals for screening under the Endocrine Disruptor Screening Program (EDSP). Since pesticides are the most commonly found EDC in water sources, this program aims to determine if exposure to pesticides has a hormonal effect caused by disruptions to the endocrine system. The initial screening process is a series of assays that will identify substances with the potential to interact with estrogen, androgen, or thyroid hormone systems, while subsequent testing will determine if these substances can affect the endocrine system. USEPA plans to screen about 87,000 compounds identified as EDC candidates. In addition, some EDCs and PPCPs are included in the UCMR3 for future regulatory consideration. As indicated above, a good deal of public interest has been aroused regarding the potential environmental and health effects of EDCs. The book, Our Stolen Future, published in 1996, gained notoriety for concluding that, "the weight of the evidence indicates that the presence of EDCs is ubiquitous" and that their presence "...involves impairments to reproduction, alterations in behavior, diminishment of intellectual capacity, and erosion in the ability to resist disease." However, these conclusions with respect to humans are subject to debate. More recently, a series of studies have related the presence of estrogenic compounds to the feminization of fish populations in streams impacted by treated wastewater. There have been some documented instances of sex abnormalities in aquatic organisms in relation to wastewater discharge, and other City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-20 possible influences in locations across the county, that are consistent with hormonal imbalances in which EDCs may play a role. Locally, an ongoing fish feminization study is being performed by the University of Colorado (David Norris). This study is comparing the sex ratios of white suckers in Boulder Creek above and below the Boulder Wastewater Treatment Plant outfall. Several estrogenic compounds are found in Boulder wastewater effluent. These include the natural estrogens, estradiol and estriol, the synthetic estrogen (from birth control pills) ethynylestradiol, a synthetic estrogen breakdown product, nonylphenol and a component of polycarbonate plastic with estrogenic effects, bisphenol A. To date, this study has found a disturbance in sucker sex ratios from a 1:1 female to male ratio above the outfall to a 5:1 female to male ratio below the outfall. In addition, intersex fish are found downstream of the outfall while none are found upstream of the outfall. These results clearly demonstrate the existence of ecological impacts from the release of treated wastewater. However, the impact to humans is not clear. This issue is complicated by the fact that consumption or contact with drinking water is only one of many pathways by which humans can be exposed to estrogenic compounds and other EDCs. It should be remembered that EDCs have been found at extremely low concentrations in drinking water. With respect to humans, it appears that even when EDCs are present in drinking water, it is likely that they are present at concentrations which are far below those that elicit a measurable physiological response. To provide some perspective on this issue, Table 5-14 presents a comparison of the maximum observed concentration of certain common pharmaceuticals found in drinking water to the predicted no effect level of these pharmaceuticals in children. As illustrated by Table 5-14, the concentrations at which these pharmaceuticals have been observed in drinking water are several orders of magnitude below the level at which they cause a physiological response. It is probable, but not certain, that as the health effects of EDCs are better understood, the concentration found in drinking water will also be much lower than the no effect concentration. 1 Ct,ili~?~' between observed and Predicted No Effect Concentration for Some Maximum Observed Predicted No Effect Compound Description Concentration (ng/L) Concentration (ng/L) Factor Acetaminophen Pain reliever 10,000 5,000,000 500 Albuterol Asthma treatment 15 41,000 2,733 Erythromycin Antibiotic 1,700 580,000 341 Gemfibrozil Cholesterol treatment 790 800,000 1,012 Ibuprofen Pain reliever 1,000 1,600,000 1,600 Norfloxacin Antibiotic 120 2,800,000 23,333 Oxytetracycline Antibiotic 340 440,000 1,294 Sulfamethoxazole Antibiotic 1,900 1,900,000 1,000 Warfarin Anti-coagulant 0.5 2,300 4,600 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-21 The City of Boulder has a proactive approach to monitoring for upcoming contaminants of concern. The City has recently started monitoring raw and finished water and is participating in regional efforts with Northern Water and other CBT entities to share costs. Below are specific discussions of potential future regulations. A few of the City's source waters have the potential of being impacted by wastewater effluent, including Barker Reservoir (via Nederland WWTP and septic tanks near Barker Reservoir) and Boulder Reservoir (via septic tanks near the reservoir and the BFC). Both of these sources are monitored frequently and sourcewater improvements have been investigated. The Nederland WWTP is upstream of a series of reservoirs and a significant amount of dilution occurs prior to entering the BWTF. The Carter Lake Pipeline would remove Boulder Reservoir as a source and pipe water directly from Carter Lake (further information is available in the City's 2007 Integrated Evaluation of the BRWTP Source Water Protection and Treatment Improvements Study). The City of Boulder is participating in several Water Research Foundation projects, including: • EDC/PPCP Benchmarking and monitoring 4260), • Building a National Utility Network to Address EDC/PPCP Issues (#4261) • Opportunity and Challenges of Nanomaterials in Drinking Water (#4311) • Evaluating the Removal of Perflurorinated Chemicals by North American Water Treatment Practices (Proposed) (#4322) • Consumer Perceptions and Attitudes Towards EDCs and PPCPs in Drinking Water (Project Advisory Committee) (#4323) 3.1.4.6 Algal Toxins Blue-green algae (cyanobacteria) are also a contaminant of concern primarily because of their ability to release harmful toxins that can contaminate drinking water supplies. The Water Research Foundation is pursuing a significant amount of work on the topic to determine the occurrence of these cyanobacteria and methods that can be used to manage it. Toxic cyanobacteria blooms should be managed in the sourcewater, but also water treatment technology, especially the use of activated carbon can be used to deal with the algal toxins. Boulder Reservoir, RWTF has shown an increase in blue-green algae, which has been shown to impact taste and odor and is an issue for the BRWTF. Microscopic analysis has shown that the blue-green algae comprise 0.6% of the biovolume (July 2010 sample). The BRWTF may require activated carbon to address the taste and odor problems, but the pilot sodium permanganate pre feed also should help resolve the issue. The City is proactively checking for the presence of these algal toxins, but has not had any problems with cyanobacteria blooms in the reservoir. Cyanotoxins are included in the CCL3. 3.1.4.7 Nitrosamines Another class of contaminants of possible future regulatory concern is nitrosamines. Nitrosamines are a family of contaminants that may be produced by the interaction of nitrogen compounds and disinfectants during the wastewater treatment process. There are other industrial sources for nitrosamines as well. Some nitrosamine compounds have been shown to cause cancer in laboratory animals. The nitrosamine family of contaminants includes: • N-Nitrosodiethylamine (NDEA) • N-Nitrosodimethylamine (NDMA) City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-22 • N-Nitrosodi-n-propylamine (NDPA) • N-Nitrosodi-n-butylamine (NDBA) • N-Nitrosomethylethylamine (NMEA) • N-Nitrosopiperidine (NPIP) • N-Nitrosopyrrolidine (NYPR) At present, neither the USEPA nor CDPHE has established regulations for nitrosamines in drinking water nationally or in Colorado respectively. However, in part because of concerns over indirect potable reuse, the State of California has established "Notification Levels" and "Response Levels" for certain nitrosamines. A Notification Level is a level that, when detected, requires that the local governing board for the utility be notified of the presence of the contaminant in the drinking water source. In California, the Notification Level is typically set at a lifetime cancer risk of 10-6 (1 in 1,000,000 risk). The Response Level is the level at which the State recommend that the source be taken out of service. In general, California drinking water utilities have voluntarily complied with these levels. Table 5-15 presents the Notification and Response Levels for nitrosamines in California. Notification Level Response Level Nitrosamine 10-6 Risk Level (ng/L) (ng/L) (ng/L) N-Nitrosodiethylamine (NDEA) 1 10 100 N-Nitrosodimethylamine (NDMA) 2 10 200 N-Nitrosodi-n-propylamine (NDPA) 5 10 500 N-Nitrosodi-n-butylamine (NDBA) 3 - - N-Nitrosomethylethylamine (NMEA) 1.5 - - N-Nitrosopiperidine (NPIP) 3.5 - - N-Nitrosopyrrolidine (NYPR) 1.5 - - The City of Boulder participated in the monitoring of 6 nitrosamines as part of the UCMR2 in 2009. None were detected. The USEPA is reviewing the results of the UCMR2 and will soon determine whether monitoring is warranted. 3.1.4.8 Carcinogens The USEPA is considering a new strategy to tighten restrictions on four waterborne compounds that can cause cancer. The four compounds to be addressed as a group are tetrachloroethylene (PCE), an organic compound used in dry cleaning; trichloroethylene (TCE), an organic compound used as an industrial solvent; acrylamide, a compound used in manufacturing; and epichlorohydrin, an organic compound used in plastic manufacturing. Under the new strategy being explored by USEPA, the agency would address chemical contaminants as a group for more expeditious and cost-effective enforcement. This strategy would also foster development of new water-treatment technologies, and partnerships with states to better monitor public water systems. 3.1.4.9 Drinking Water Strategy The USEPA announced in early 2010 that a new drinking water strategy is being developed to address a range of drinking water quality concerns and is expected to streamline and accelerate the regulatory development process. The USEPA's March 2010 Fact Sheet on this matter states that there will be four principles that will provide greater protection of drinking water. The four principles are. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-23 • Address contaminants as a groups rather than one at a time so that enhancement of drinking water protection can be achieved cost-effectively. • Foster development of new drinking water technologies to address health risks posed by a broad array of contaminants. • Use the authority of multiple statutes to help protect drinking water. • Partner with states to share more complete data from monitoring at public water systems (PWS). 3.1.5 State of Colorado Regulations 3.1.5.1 Cross Connection Control Policy This Policy addresses Article 12 of the Colorado Primary Drinking Water Regulations that states a public water system shall have no uncontrolled cross-connections to a pipe, fixture, or supply, any of which contain water not meeting provisions of the drinking water regulations. This regulation required the City of Boulder to implement a backflow prevention program to try to reduce the potential for cross connections to occur. 3.1.5.2 Waste Impoundment Regulations As a result of subsection 25-8-202(7) of the 1989 amendments to the Colorado Water Quality Control Act (Senate Bill 181), a memorandum of agreement (MOA) was implemented on July 31, 2008, by and between the Water Quality Control Commission (WQCC), Water Quality Control Division (WQCD), and the Hazardous Materials and Waste Management Division (HMWMD) to provide a procedure for coordination among the Colorado State agencies that are responsible for protecting the quality of the state waters. The MOA states that the HMWMD will be the agency responsible for implementing site- specific standards for discharges into state ground waters through a rulemaking process and consultation with the WQCC and WQCD. The HMWMD rule will be established to protect present and future beneficial uses of groundwater. As a result of the Senate Bill 181 and the MCA, the HMWMD is currently in the process of modifying Section 9 of the solid waste regulations (6 CCR 1007-2). The rule will apply to all waste impoundments where deposit and final treatment of solid waste occurs, and where storage, treatment, utilization, processing, or disposal of solid waste occurs. The HMWMD has targeted November 2010 for adoption of the Section 9 regulation. Municipal utilities that possess solid waste impoundments will be confronted with new regulatory requirements and associated compliance schedules. The following are examples of impoundments at water treatment facilities that are likely to be affected: • Filter backwash ponds • Post-process waste storage ponds • Washwater recovery ponds • Drying/evaporation beds/pads Exemptions to the regulations are defined in the draft regulation and include storm water and raw water impoundments, tanks, and impoundments that contain water in process. Two categories of waste impoundments are defined based on their potential environmental threat: Type A and Type B impoundments. Classification will be determined by evaluating the waste stream characteristics and geologic, hydrogeologic, and engineering characteristics of the facility. Factors such City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-24 as waste constituents, toxicity, mobility, and persistence in the environment will also be considered in determining a facility's classification. The current proposed impoundment classification assumes that the impoundments will be Type A and does not require additional engineering controls beyond those already in existence as of the effective date of the regulations. Impoundments that contain low-threat wastes and allow controlled seepage through their liner are classified as Type A impoundments. Seepage is only allowed from Type A impoundments that have no impact to the groundwater. Type B impoundments are designed to prevent seepage or migration of leachable contaminants to groundwater and allow no seepage beneath their liner. Type B impoundments require additional engineering controls beyond to prevent the migration of leachable constituents to groundwater. 3.1.5.3 Residuals Treatment and Disposal The disposal of solid wastes from water treatment residuals/sludge (WTRs) is under dual authority of the CDHPE and the local body having jurisdiction, typically the County's health department. Disposal of solid waste can be through beneficial reuse (land application or composting) or direct disposal (landfill). Beneficial reuse is regulated by 5 CCR 1003-7 Regulations pertaining to the Beneficial Use of Water Treatment Sludge. The key component of 5 CCR 1003-7 requires that the producer of the sludge to obtain a "Beneficial Use Certification" from CDPHE for land application. Parameters that must be monitored in water treatment plant sludge for Beneficial Use Certification are: TSS Nitrate Total cadmium Total lead Total selenium pH Total potassium Total chromium Total mercury Total zinc Organic nitrogen Total aluminum Total copper Total molybdenum Total alpha activity Total ammonia Total arsenic Total iron Total nickel Total phosphorous Per 5 CCR 1003-7, the parameters listed above must be less than those established in 40 CFR 503 Standards For The Use Or Disposal of Sewage Sludge to obtain a Beneficial Use Certification. Of particular importance is the total alpha activity parameter. Per 5 CCR 1003-7 any dry sludge which exceeds 40 pCi/gm total alpha activity cannot be land applied. If the water treatment plant waste is co- applied with wastewater treatment plant biosolids, the requirements of Biosolids Regulation No. 64 are also applicable. Direct disposal of WTRs is regulated through the Hazardous Materials and Waste Management Division of CDPHE. A key regulation is 6 CCR 1007-3 Part 261, Identification and Listing of Hazardous Wastes. To be disposed of in a non-hazardous landfill, the solid must pass limits set for the Toxicity Characteristic Leaching Procedure (TCLP) described in Part 261.24. Water treatment plant sludges routinely pass the TCLP and can be disposed of in non-hazardous landfills. Requirements defining the responsibilities of the facility accepting the sludge are defined in 6 CCR 1007-2, Part 1 Regulations Pertaining to Solid Waste Sites and Facilities. Section 12 of 6 CCR 1007-2, Part 1, specifically establishes criteria for water treatment plant sludge disposal facilities. 3.1.5.4 Technologically Enhanced Naturally Occurring Radioactive Materials (TENORMs) Specific regulations regarding the disposal of WTRs containing TENORMs are unclear at present. The USEPA has released a guidance document for WTRs titled: "A Regulators' Guide to the Management of Radioactive Residuals from Drinking Water Technologies." The CDPHE has released an Interim Policy and Guidance Pending Rulemaking for Control and Disposition of Technologically-Enhanced Naturally Occurring Radioactive Materials in Colorado (February, 2007) to provide disposal policy, general City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-25 guidance and suggested criteria for the control and release of technologically enhanced naturally occurring radioactive material. The interim policy describes a tiered, graded approach acceptable to the CDPHE for disposal or reuse of TENORM, primarily from the treatment of drinking water, but may also be applied to other diffuse sources on a case-by-case basis. Section 12 of the Solid Waste Regulations (6 CCR 1007-2 Regulations Pertaining To Solid Waste Disposal Sites and Facilities.) spells out the requirements for disposal of drinking water treatment plant sludge. Disposal also includes the requirements of Sections 2 and 3 of the Solid Waste Regulations. • 12.1.4 Surface and Groundwater Monitoring - states that surface and groundwater monitoring may be required. Facilities that are out of compliance with current standards may be required to upgrade to meet surface and groundwater protection. • 12.2.1 - this section has the 40 pCi/g gross alpha notification requirement for alum sludge for drinking water treatment plants. • 12.2.2 - this section has design, operation and closure requirements for monofills. Subsequent sections have requirements for fencing, maps, and record keeping. • 12.3 - this section has sludge Acceptance criteria concerning pH and the presence of free liquids and other parameters. No other type of waste may be accepted by a monofill without approval by the Department, consistent with local land use authority. At the present time, the City of Boulder is required to be in compliance with the Colorado Primary Drinking Water Regulations and the National Primary Drinking Water Standards. The regulatory requirements specifically applicable to the City of Boulder and the City's current status relative to the regulatory limits are presented in the following paragraphs. 3.1.6.1 The City of Boulder's Regulatory Drinking Water Quality Monitoring Schedule Table 5-16 shows the drinking water quality monitoring schedule. Note that the table includes regulatory and supplemental monitoring. The table does not include regular process monitoring within the treatment facilities, source water monitoring, or special studies. The table was provided by the City of Boulder. z sort _o~s wur Contaminant Sample Location Frequency Report To CDPHE Regulatory Inorganics Fluoride Ent point to the distributions stem Annually 10 days after results received Metals (Sb, As, Ba, Be, Entry point to the distribution system Annually 10 days after results received Cd, Cr, Hg, Ni, Se, Na, TI Nitrate Ent point to the distributions stem Annually 10 days after results received Nitrite Entry point to the distribution system Every 9 years - next monitoring in 2017 10 days after results received Turbidity Entry point to the distribution system Daily (six times/day) End of month + 10 days and continuous Organics Synthetic organics Entry point to the distribution system Triennially - next 10 days after results received monitoring in 2012 Volatile organics Ent point to the distributions stem Annually 10 days after results received City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-26 Contaminant Sample Location Frequency Report To CDPHE Disinfection Byproducts and Precursors TOC removal and alkalinity (plus DOC and Raw water Monthly - one set UV254 for Specific UV- entry point to distribution paired samples End of quarter + 10 days absorption (SUVA) system (source and treated) calculation at BRWTF Disinfection byproducts Quarterly - 8 sites in (TTHM, HAAS) Distribution system third month of each End of quarter + 10 days quarter Monthly -120 samples using Chlorine MRDL Distribution system chlorine residual End of quarter + 10 days data from total (with TCR report) coliform rule monitoring Chlorine Entry point to distribution system Daily (six times/day) End of month + 10 days and continuous Total Coliform Rule Total coliform Distribution system Monthly -120 End of month + 10 day samples Lead and Copper Rule LCR at the tap (copper, Triennially - 50 End of sample period + 10 lead, pH, alkalinity, At customer taps samples. Next days hardness monitoring in 2011 Quarterly -10 sites LCR Corrosion Control Distribution system and entry points to twice every 6 months End of 6 months + 10 days (pH, alkalinity, hardness) distribution system (usually performed quarterly) Surface Water Treatment Rule Microscopic particulate Annually - rotating analysis Raw water and combined filter effluent quarters. Quarter 4 10 days after results received in 2010 Radionuclides Uranium, Radium226,228, Every 9 years - next Gross AI ha Entry point to distribution system monitoring in 2011 10 days after results received Supplemental Monitoring, Regularly Scheduled Metals Cu, Pb, As Ent point to distributions stem Monthly, Each WTF Not required DBPs TTHM, HAAS Ent point to distributions stem Monthly, Each WTF Not required Chlorine, turbidity, pH, Booton and Chautauqua tanks and Iris conductivity, and and Cherryvale pump stations Continuous Not required temperature 3.1.6.2 National Primary Drinking Water Standards A National Primary Drinking Water Regulation (NPDWR or primary standard) is a legally-enforceable standard that applies to public water systems. Primary standards protect drinking water quality by limiting the levels of specific contaminants that can adversely affect public health and are known or anticipated to occur in water. The primary standards take the form of Maximum Contaminant Levels or Treatment Techniques- The Primary Drinking Water Standards (CFR 40 Part 141) regulate a broad range of chemical, physical, and microbial contaminants in drinking water. The regulations also stipulate frequency of water quality monitoring, analytical methods, reporting and record keeping requirements, and public notification of City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-27 compliance failures. The Primary Drinking Water Standards, including the MCLs, and monitoring requirements as they apply to the City of Boulder are summarized in Table 5-17, 5-18, and Table 5-19. In each of these tables the column headed "Boulder" presents average water quality data as reported by the City, for comparison to regulatory limits. Values listed as "less than" indicated by the symbol represent measurements that were below the numerical limit given as the lowest detectable concentration. A reported value of "NY indicates that the constituent was not detected by the method used without stating the numerical detection limit concentration. Both designations signify that the given parameter was not present in the tested sample. A reported value of "NM" indicates the constituent was not measured, likely because it was not required. As can be seen in the previous tables, the City has had no problem meeting the requirements of the National Primary Drinking Water Regulations. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-28 7-17: National Prim rv Drinking Water Regulations - Inorganic Chemicnlr Boulder Contaminants MCL or TT (mg/L) (mg/L) Health Effects from Contaminant Monitoring Requirements Once per year for surface waters not including Antimony 0.006 <0.001 Increase in blood cholesterol; decrease in blood glucose Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides Arsenic 0.010 <0.001 Skin damage; circulatory system problems; increased risk of cancer Asbestos (fiber > 10 7 MFL NM Increased risk of developing benign intestinal polyps Asbestos - Once every nine years micrometers) Barium 2 0.028 Increase in blood pressure Beryllium 0.004 <0.001 Intestinal lesions Cadmium 0.005 <0.0006 Kidney damage Some people who use water containing chromium well Chromium 0.1 <0.02 in excess of the MCL over many years could experience allergic dermatitis Short term exposure: Gastrointestinal distress. Long Copper Action Level =1.3; TT 0.0023 Same as lead term exposure: Liver or kidney damage. Cyanide (as free 0.2 NM Nerve damage or thyroid problems cyanide) Fluoride 4.0 0473 Bone disease (pain and tenderness of the bones); Children may get mottled teeth. Gross Alpha Emitters 15pCi/L ND Cancer Risk Gross alpha and beta: Every four years - quarterly samples Gross beta Particle 4mrem ND Cancer Risk and Photon Emitters Follow-up monitoring is every six months after • Infants and children: Delays in physical or mental corrosion controls are initiated or optimized. Lead Action Level = 0.015; TT <0.0005 development Systems consistently meeting action levels • Adults: Kidney problems; high blood pressure can reduce monitoring to annually and then to every three years. Inorganic Mercury 0.002 <0.0002 Kidney damage Nitrate (measured as 10 <02 "Blue baby syndrome" in infants under six months - life Nitrate: Groundwater annually; Surface water Nitrogen) threatening without immediate medical attention. quarterly City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-29 Boulder Contaminants MCL or TT (mg/L) (mg/L) Health Effects from Contaminant Monitoring Requirements Nitrite (measured as 1 <01 "Blue baby syndrome" in infants under six months - life Nitrite: One sample every three years. Nitrogen) threatening without immediate medical attention. Radium 5 pCi/l combined <1 pCill combined Cancer risk Radium: Every nine years Selenium 0.05 <0.001 Hair or fingernail loss; numbness in fingers or toes; circulatory problems Thallium 0.002 <0.001 Hair loss; changes in blood; kidney, intestine, or liver problems City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-30 Table 5-18: .`..,x,;3.1 PrimT- q Water Regulations -Synthetic Organics MCL or TT MCLG Boulder Organic Chemicals (mglL) (mg/L) (mg1L) Health Effects from Contaminants Synthetic Organics Dioxin (2,3,7,8-TODD) 3 X 10-8 0 NM Reproductive difficulties; increased risk of cancer 2,4,5-TP (Silvex) 0.05 0.05 <0.0002 Liver problems 2,4-D 0.07 0.07 <0.0001 Kidney, liver, or adrenal gland problems Acrylamide TT NIA NM Nervous system or blood problems; increased risk of cancer Alachlor 0.002 0 <0.00005 Eye, liver, kidney or spleen problems; anemia-, increased risk of cancer Aldicarb 0.0031 0.001 <0.0005 Aldicarb sulfoxide 0.0041 0.001 <0.0005 Aldicarb sulfone 0.0021 0.001 <0.0005 Atrazine 0.003 0.003 <0.00005 Cardiovascular system problems; reproductive difficulties Carbofuran 0.04 0.04 <0.0005 Problems with blood or nervous system-, reproductive difficulties. Chlordane 0.002 0 <0.0001 Liver or nervous system problems; increased risk of cancer Dalapon 0.2 0.2 <0.001 Minor kidney changes Di(2-ethylhexyl)adipate 0.4 0.4 <0.0006 General toxic effects or reproductive difficulties 1,2-Dibromo-3-chloropropane (DBCP) 0.0002 0 <0.00001 Reproductive difficulties; increased risk of cancer Di(2-ethylhexyl)phthalate 0.006 0 <0.0006 Reproductive difficulties; liver problems-, increased risk of cancer Dinoseb 0.007 0.007 <0.0002 Reproductive difficulties Diquat 0.02 0.02 <0.0004 Cataracts Endothall 0.1 0.1 <0.005 Stomach and intestinal problems Endrin 0.002 0.002 <0.00001 Nervous system effects Epichlorohydrin TT N/A NM Stomach problems; reproductive difficulties; increased risk of cancer Ethelyne dibromide 0.00005 0 <0.00001 Stomach problems; reproductive difficulties; increased risk of cancer Glyphosate 0.7 0.7 <0.006 Kidney problems; reproductive difficulties Heptachlor 0.0004 0 <0.00001 Liver damage; increased risk of cancer Heptachlor epoxide 0.0002 0 <0.00001 Liver damage; increased risk of cancer Hexachlorobenzene 0.001 0 <0.00005 Liver or kidney problems; reproductive difficulties; increased risk of cancer Hexachlorocyclopentadiene 0.05 0.05 <0.0005 Kidney or stomach problems Lindane 0.0002 0.0002 <0.00001 Liver or kidney problems Methoxychlor 0.04 0.4 <0.00005 Reproductive difficulties Oxamyl (Vydate) 0.2 0.2 <0.0005 Slight nervous system effects Benzo(a)pyrene (PAHs) 0.0002 0 <0.00002 Reproductive difficulties; increased risk of cancer City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-31 MCL or TT MCLG Boulder Organic Chemicals (mglL) (mg/L) (mg/L) Health Effects from Contaminants Polychlorinated biphenyls (PCBs) 0.0005 0 ND Skin changes; thymus gland problems; immune deficiencies; reproductive or nervous system difficulties; increased risk of cancer Pentachlorophenol 0.001 0 ND Liver or kidney problems; increased risk of cancer Picloram 0.5 0.5 <0.00001 Liver problems Simazine 0.004 0.004 <0.00005 Problems with blood Toxaphene 0.003 0 <0.0005 Kidney, liver, or thyroid problems; increased risk of cancer 'The aldicarbs are currently under an "administrative stay' due to litigation. No limit is in effect until resolved. Monitoring Requirements Original monitoring required four quarterly samples every three years. After one round of no detects; systems > 3,300 reduce to two samples per year every three years. Systems < 3,300 reduce to one sample every three years. Monitoring may be reduced or eliminated based on the results of the vulnerability assessment. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-32 Table= ° -",-)nal Primar g Water Regulations - Volatile MCL or TT MCLG Boulder Organic Chemicals (mg/L) (mg/L) (mg/L) Health Effects from Contaminants 1,1,1-Trichloroethane 0.2 0 <0.0005 Liver, nervous system, or circulatory problems 1,1,2-Trichloroethane 0.005 0.003 <0.0005 Liver, kidney, or immune system problems 1-1-Dichloroethylene 0.007 0.007 <0.0005 Liver problems 1,2,4-Trichlorobenzene 0.07 0.07 <0.0005 Changes in adrenal glands 1,2-Dichloroethane 0.005 0 <0.0005 Increased risk of cancer 1-2-Dichloropropane 0.005 0 <0.0005 Increased risk of cancer Benzene 0.005 0 <0.0005 Anemia; decrease in blood platelets; increased risk of cancer Carbon tetrachloride .005 0 <0.0005 Liver problems; increased risk of cancer Chlorobenzene 0.1 <0.0005 Liver or kidney problems cis-1, 2-Dichloroethylene 0.07 0.07 <0.0005 Liver problems Dichloromethane 0.005 0 <0.0005 Liver problems; increased risk of cancer Ethylbenzene 0.7 07 <0.0005 Liver or kidney problems o-Dichlorobe nzene 0.6 0.6 <0.0005 Liver, kidney, or circulatory system problems Para-Dichlorobenzene 0.075 0.075 ND Anemia; liver, kidney or spleen damage; changes in blood Styrene 0.1 0.1 <0.0005 Liver, kidney, and circulatory problems Tetrachloroethylene 0.005 0 <0.0005 Liver problems; increased risk of cancer Toluene 1 1 <0.0005 Nervous system, kidney, or liver problems trans- 1,2-Dichloroethylene 0.1 0.1 <0.0005 Liver problems Trichloroethylene 0.005 0 <0.0005 Liver problems; increased risk of cancer Vinyl chloride 0.002 0 <0.0005 Increased risk of cancer Xylenes (total) 10 10 <0.0005 Nervous system damage Monitoring Requirements VOCs: Original monitoring required four quarterly samples during the first three years. Monitoring annually beginning in 1996 if no detects. Monitor every three years after three years of no detects Monitoring may be reduced based upon results of vulnerability assessment. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-33 3.1.6.3 Secondary Standards National Secondary Drinking Water Regulations (NSDWRs or secondary standards) are non-enforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. USEPA recommends secondary standards to water systems but does not require systems to comply. However, states may choose to adopt them as enforceable standards. Table 5-20 below summarizes the secondary standards. Contaminant Secondary Standard Aluminum 0.05 to 0.2 mg/L Chloride 250 mg/L Color 15 (color units) Copper 1.0 mg/L Corrosivity Noncorrosive Fluoride' 2.0 mg/L Foaming Agents 0.5 mg/L Iron 0.3 mg/L Manganese 0.05 mg/L Odor 3 threshold odor number PH 6.5-8.5 Silver 0.10 mg/L Sulfate 250 mg/L Total Dissolved Solids 500 mg/L Zinc 5 mg/L 'When fluoride levels exceed 2.0 mg/L; public notification in accordance within Article 9 is required. 3.1.6.4 Regulatory Compliance • Inorganics Sampling results from the Safe Drinking Water Act analysis conducted at the BWTF and BRWTF indicate that there are no inorganic contaminants at levels of concern at this time. • Volatile Organic Compounds Sampling results from the Safe Drinking Water Act analysis conducted at the BWTF and BRWTF indicate that there are no Volatile Organic Compound contaminants at levels of concern at this time- • Synthetic Organic Compounds Sampling results from the Safe Drinking Water Act analysis conducted at the BWTF and BRWTF indicate that there are no Synthetic Organic Compound contaminants at levels of concern at this time. 3.1.6.4.1 Total Coliform Rule The City of Boulder collects 100 total coliform samples per month in the distribution system as required by the TCR_ Bacteriological sampling conducted since 1997 has shown an excellent history of "safe" samples in the distribution system. Current practices are adequate to meet the requirements of this rule, however, operational or infrastructure modifications may result in improved disinfection performance and bacteriological stability- A more detailed discussion of regulatory compliance is included in Section 5.1.3. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-34 3.1.6.4.2 S.;rface Dater Treatment Rule Turbidity levels at the water treatment plants are meeting the 5 NTU maximum and the 0.5 NTU limit at the 95th percentile monthly based on 4-hour monitoring intervals. Current disinfection practices result in adequate disinfection residual leaving the water treatment plants. However, due to long residence times and chlorine demand, the free chlorine residual does fall to near zero in parts of the distribution system. Long residence times are compounded by poor treated water storage reservoir circulation, which is reported to be particularly severe in the Chautauqua, Booton, and Gunbarrel reservoirs. A more detailed discussion of regulatory compliance is included in Section 5.1.3. 3.1.6.4.3 Lead and p:; e Rule Lead and copper sampling (Table 5-15) has shown that the 90th percentile concentrations in the City's water have been below the Safe Drinking Water Act established drinking water action levels of 1,300 pg/I for copper and 15 pg/I for lead. For the purposes of the rule, the City of Boulder is considered as having optimized treatment for corrosion control and no further actions are required at this time. Boulder will remain on the minimum required monitoring schedule for these two corrosion by-product parameters- A more detailed discussion of regulatory compliance is included in Section 5.1.3. In summary, The City of Boulder has not exceeded Action Levels for either lead or copper in any of the monitoring done to date. Since the monitoring began in 1992, the number of residences exceeding the 0.015 mg/L lead limit has varied between 0 and 10% (most recent monitoring 0%). To date, no sites have exceeded the 1.3 mg/L copper action limit. 3.1.6.4.4 Arsenic The MCLs for Arsenic is 10 ppb. The City of Boulder's water quality data indicates that arsenic levels are undetectable or less than 1 ppb, well below the MCL. 3.1.6.4.5 SI'age 2 D DBPR and LT2ESVVTR The Stage 2 D/DBPR was implemented in 2006. The rule only applies to utilities serving more than 10,000 consumers. The City of Boulder has not exceeded the current regulatory limits for THMs and HAA5s. The LT2ESWTR was adopted in 2006 and applies to surface water and groundwater under the direct influence of surface water sources. The objective of the rule is to reduce the risk associated with Cryptosporidium and other microbial pathogens in drinking water and address risk-risk tradeoffs with the control of disinfection byproducts. Sampling of raw water sources for Cryptosporidium is required under the LT2ESWTR. A more detailed discussion of regulatory compliance is included in Section 5.1.3. 3.i.6.~;.6 Filter Backwash Rule The City of Boulder has records which comply with the requirements for this rule. 3. i .4 7 RadioiluClid es R_ 1- The City does not have any problems meeting the requirements of this rule. Boulder is in compliance with all of the existing radiological parameters. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-35 3.2 City of Boulder Water Quality Goals The City's Water Treatment Operations Group operates the treatment and distribution facilities following various internal procedures and guidelines developed over time to ensure that treated water quality objectives are consistently met. To facilitate treatment operations, most water providers use a set of internal standards for key water quality parameters as targets to guide process control decisions. Typically, the targets are more stringent than the applicable regulatory requirements so that operating treatment processes to meet the internal targets ensures that the treated water delivered to customers not only complies with all regulatory requirements but is of the highest practical quality. Boulder's treatment facilities are currently operated to meet a set internal standards developed from process performance criteria commonly used in the water industry and recommended by USEPA and AWWA. These operating targets meet the Utility's objectives for protecting public health and providing high quality treated water. Table 5-21 shows the overall summary of operating targets for both facilities. Parameter Regulatory Requirements BWTF BRWTF Turbidity Post Sedimentation NIA <1.0 NTU <1.0 NTU Filtered Water < 0.3 NTU in 95% of samples, never > 1.49 NTU <0.1 NTU <0.1 NTU Finished Water N/A <0.1 NTU <0.25 NTU Filtration Filter Run Time NIA 48 hrs 60 hrs < 0.5 NTU within 4 hours of filter start-up < 1 NTU Win 15 min < 1 NTU w/in 15 min Initial turbidity spike < 1 NTU within 15 minute filter start-up of filter startup of filter startup Particle Counts N/A <100 <100 Finished Water 15-98 mg/L (per CDPHE). Cannot exceed more 45 ± 3.0 mg/L 15-98 mg/L Alkalinity than 9 days in 6 month period. pH 7.1 - 8.2 (SMCL). Cannot exceed more than 9 7.8 ± 0.2 7.8 ± 0.2 days in 6 month period. Fluoride 4.0 mg/L (MCL) 0.9 ± 0.1 mg/L 0.9 ± 0.1 mg/L 2.0 mg/L (SMCL) Free Chlorine Not < 0.2 mg/L for more than 4 hours or < 4.0 1.0 ± 0.1 mg/L 1.0 ± 0.1 mg/L mg/L in distribution system With these targets met, the water treatment plants can reliably produce high quality water for the citizens of Boulder. The goals specific to each treatment facility, including actions to be taken is included in Appendix B. The City of Boulder has an optimization program for the water treatment plants. The objective of the program is to identify operational and physical factors that could be limiting current treatment performance and facilitate improvements that would enhance performance, fully utilize facilities and resources, and, when possible, reduce operating costs. Currently, the operations staff includes two process optimization specialists. Their efforts are coordinated and directed by a team comprised of the Water Treatment Operations Coordinator, the two Water Treatment Plant Supervisors, the Water Quality Group Supervisor, and a Representative from the Project Management Group. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 3-36 4 Treatment and Distribution Facilities Studies A summary of each of the following reports can be found in this section: • City of Boulder Water Conservation Futures Study; Hydrosphere Resource Consultants, Inc. (1999) • 2000 Treated Water Master Plan; Integra Engineering (2000) • 2000 Treated Water Master Plan Recommendations and Implementation Plan Findings and Basis for Plan, Integra Engineering (2000) • Boulder Reservoir Water Treatment Plant Predesign Report (2003), Including an Evaluation of Mid-Term and Long-Term Improvements for the Facility • Boulder Reservoir Water Treatment Plant Source Water Quality Planning Study (Phase I Study) (2003) • City of Boulder Zone 1 Distribution System Analysis (2003) • Betasso Water Treatment Plant Facility Improvement Plan (2005) • Integrated Evaluation of the BRWTP Source Water Protection and Treatment Improvements Study (Integrated Study) (2007) • AWWA Peer Review Report (2008) • City of Boulder Water Conservation Plan (2009) 4.1 City of Boulder Water Conservation Futures Study; 1999, Hydrosphere Resource Consultants, Inc. This study was prepared to 1) examine Boulder's existing water use patterns and recent trends, 2) update Boulder's future water demand projections and reliable supply capability, and 3) reassess the role of water conservation programs in helping to meet Boulder's needs, not only in the area of treated water supply, but in several important and related areas. Most of the information presented in this document was updated in Volume 2 and in the Source Water Management Plan (SWMP). Key recommendations from this report included: • Adopt the Comprehensive Conservation Scenario as defined in the Water Conservation Futures Study. The Comprehensive Conservation scenario promotes the indoor and outdoor conservation measures most likely to have a lasting impact on demand in the City. This program would increase the City's current water conservation budget substantially, but would reduce future peak demand to a level that can be handled by current facilities upgraded to their rated capacities. > Move into the design phase to flesh out the specific elements of the program and solicit community input. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-1 > Develop environmental and community-based conservation targets and rewards. Citizens have expressed a strong desire to conserve water because "it is the right thing to do" for the environment and Boulder's watershed. The City should develop a program of annual conservation goals and rewards. Under this program, the City would pledge to dedicate raw water to in-stream flow and other beneficial purposes (community gardens, agricultural leasing, etc.) if annual conservation targets are achieved. These goals should include annual peak water demands and specific program level of effort goals such as the installation of ULF toilets, or distribution of clothes washer and Xeriscape rebates. > Develop an independent, comprehensive program of monitoring, evaluation, and reporting to ensure that the conservation program is accomplishing the established goals. Consideration should be given to linking the conservation program to an allocation billing system. > Evaluate the City's water treatment plant flow meters, and implement system-wide leak detection if necessary. The reported 8.4 percent unaccounted for water may not be correct due to underreporting by the flow meters at the City's water treatment plants. The City should hire an independent expert to examine and evaluate the flow meters at both plants. If necessary, meters should be replaced so that the true extent of the unaccounted water in the City's system can be determined. If the treatment plant meters have been underreporting, the City should correct its water accounting accordingly, and implement a leak-detection and repair program if called for. • Adopt a peak ratio of 2.6 for water treatment plant capacity planning purposes. Assuming that additional conservation measures aimed at peak demand reductions are pursued, this peak ratio could be further reduced. • Study the allocation billing system option. An allocation billing system would develop a specific water allocation for each account in the City's system based on factors specific to each account. An allocation water billing system could be an effective conservation tool and an extremely fair method for apportioning costs by charging users according to the burden they place upon the system over and above reasonable levels of use. The 1999 Water Conservation Futures Study was used to develop the Water Conservation Plan which was adopted by the City of Boulder and approved by the Colorado Water Conservation Board in 2009. Most of the information presented in this document was updated in the Water Conservation Plan as well as Volume 1 and 2 of the Source Water Management Plan (SWMP). 4.2 Treated Water Master Plan; 2000, Integra Engineering The 2000 TWMP was the previous update to the overall treated water system. The key findings of this report associated with the treatment and distribution systems as reported in December of 2000 include: • The report defined the study area, service area, and planning period (20 years) for the study. It also projected an average day water use of 21.6 MGD (24,159 acre-ft). With water conservation measures in place, it could be as low as 19.4 MGD. The Peak Day and Peak Hour estimates for 2020 were estimated to be 56.2 MGD (50.4 MGD with water conservation) and 96.1 MGD (86.3 MGD with water conservation) respectively. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-2 • BWTF > The BWTF was evaluated to have the capacity to treat a peak flow of approximately 40 MGD to the level required by the regulatory requirements. > The plant is limited by the flocculation/sedimentation process. Performance data indicated that sedimentation capacity is less than the theoretical capacity because of entrained air, poor flocculation and possibly poor coagulation. > Additional improvements will be needed to the flocculation and sedimentation basins to provide a fully effective treatment barrier with consistent performance necessary to reliably meet the regulatory requirements at a capacity of 50 MGD. • BRWTF > The BRWTF (2000) has the capacity to treat a peak flow of somewhat less than 10 MGD to the level required by regulatory requirements. > Capacity is limited by the flocculation sedimentation process which performance data suggests is over capacity when operating at 8.5 MGD. > The other processes were reported to have capacities equal to or greater than 12 MGD. Hydraulic capacity was reportedly limited to 12 MGD due to overflowing with the hydraulic jump. • Distribution System > The distribution system was evaluated and no deficiencies were identified with the transmission mains, hydroelectric generating facilities, most PRVs (with exceptions below), treated water storage. > Identified improvements included: replacement of PRVs and pumping improvements at the Iris and Cherryvale pump stations, the 4-Mile PRV facility needed to be rebuilt or eliminated. > Improvements to standardize the system operating procedure were recommended- > A number of valves were identified that block specific pipes and create pressure zone boundaries. Valve failure in one of these locations could be problematic. > An evaluation on pipe breaks was performed, but no specific correlation was found with respect to pressure. > The average age of pipe in the system is 34 years. Over 83 percent of the pipes are older than 25 years old and nearly one third is over 40 years old. > The distribution system was modeled using H2ONET hydraulic analysis software to determine flow and pressure problems within the distribution system and storage capacity adequacy. High and low pressure areas were identified in multiple locations. Storage capacity was determined to be adequate, although hydraulic problems exist. 4.3 2000 Treated Water Master Plan Recommendations and Implementation Plan Findings and Basis for Plan • The City's treated water service area will not expand significantly. Extension of service into new areas outside the existing service area will be very limited. • Build-out within the treated water service area under current land use plans will be reached by 2020. • Service area population at build-out will be between 126,000 and 127,000. • The Comprehensive Conservation Program will be adopted and successfully implemented. • Average daily water use at the 2020 build-out will be between 19.4 and 21.6 MGD with peak day water use between 50 and 56 MGD depending on effectiveness of water conservation efforts- City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-3 • Future regulatory requirements and the desire to maximize public health protection will increase the demands on treatment facilities for higher and more consistent levels of performance and place increasing emphasis on protecting water quality at the source and throughout the distribution system. • Issues Identified > Water Treatment Plant Capacity: The City's reliability criteria require a total capacity of 55 to 62 MGD whereas the two treatment plants only have a combined capacity of 48 to 50 MGD. > Water Quality Criteria: Deterioration of the Lakewood pipeline feeding the BWTF and poor performance of the flocculation/sedimentation processes at the BRWTF limits the capacity of both facilities. • Public Health Protection: Improving raw water quality, limiting disinfection byproduct formation, and removing pathogenic organisms from the water, and maintaining the quality of the water in the distribution system will help to protect public health. • Operability and Reliability: The following were issues identified in this category: > Operation of the BRWTF is of the most notable operability issues identified. Seasonal switching and start/stop operation are difficult to manage. > High turbidity during summer runoff events can cause treatment issues- > Inefficient performance of the flocculation/sedimentation process at both facilities. > SCADA improvements are needed. > Standardization of operating procedures is needed. • A recommendation for the capital improvement program (CIP) is included in this report. Improvements were prioritized, costs developed, and an implementation schedule identified. • Future Studies: Implementation of the recommendations will require further study of many of the recommendations. The report lists the recommended studies. • Planning Process: The report recommends both public participation and coordination with related planning programs to ensure a continued evaluation of the master plan goals and implementation of the identified recommendations. 4.4 Boulder Reservoir Water Treatment Plant Predesign Report (2003), Including an Evaluation of Mid-Term and Long-Term Improvements for the Facility This report presented the near-term, mid-term, and long-term recommendations for improvements to BRWTF in 2003. Near-term improvements included: • DAF pretreatment • Clearwell Baffling • Pumps • Residuals Lagoons • I&C improvements City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-4 • Pilot Facility - purchase used pilot facility from DAF manufacturer as part of BRWTF equipment procurement Mid-term Improvements included: • Chlorine dioxide for pre-oxidation. • Additional residuals lagoons and/or accelerated dewatering system for all residuals production at 10 MGD average annual flow rate. • Decant/filtrate pumps and piping for lagoon decant return to BRWTF. • I&C improvements, including PLC integration, automated backwash, filter instrumentation, SCADA reconfiguration, and enhanced process trending. • New raw water pump. • Waste washwater treatment with stand-alone structure with gravity plate settler units • Conversion of remainder of pretreatment basin to conventional settling presedimentation unit with plate settlers. • CO2 pH adjustment system. Long-term improvements include: • Supervisory control and data acquisition (SCADA) expansion. • New clearwell reservoir. • New pretreatment train. • UV disinfection for control of Cryptosporidium (not warranted if membrane filtration is used)- • Emergency power addition. • Membranes (warranted if plant hydraulics ultimately limit capacity of granular media filters). • GAC caps in existing granular media filters (if membranes not used). Used to control taste and odors. Order of magnitude costs for O&M and capital costs were prepared for all of the improvements. This report includes the preliminary design information for the near-term improvements. 4.5 Boulder Reservoir Water Treatment Plant Source Water Quality Planning Study (Phase I Study) (2003) This study evaluated the alternatives available to improve and protect the BRWTF source water quality. The primary source of BRWTF raw water is Carter Lake. Raw water is delivered through a 21 mile open canal known as the BFC. The BFC can discharge water either directly to the BRWTF or to Boulder Reservoir for pumping to the BRWTF. Based on historical monitoring of the raw water entering the BRWTF, additional removal treatment for Cryptosporidium will be required under this operational mode as part of the Long-Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR)_ The alternatives evaluated for source water quality management included: • Existing Source Water System (to be used as a baseline) • Boulder Reservoir Management (using Boulder Reservoir as a year-around terminal reservoir) • Full Containment from Carter lake to the BRWTF (21-mile raw water gravity pipeline from Carter Lake to BRWTF for year-around basis) • Partial Containment from Nelson Road to the BRWTF (partial canal, partial gravity pipeline. When canal is out of service for winter, water would have to be pumped from the Boulder Reservoir) • New Terminal Reservoir (new reservoir upstream of the Boulder Reservoir) City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-5 • New Forebay (new earthen forebay to allow for dilution and settling to reduce contaminant load) The alternative evaluation resulted in the narrowing down of the list to two alternatives: the Boulder Reservoir Management and the Full Containment alternative. The full containment option was preferred, however would involve a major commitment of capital funds by the City_ The Boulder Reservoir management option would provide immediate reductions in the occurrence of microbial pathogens and compliance with the LT2ESWTR, but the City would need to take steps to address the seasonal uptake of manganese. The result of this evaluation was to recommend a Phase 2 investigation into these two alternatives, including the following tasks: • Consider the preferred source water management alternatives identified in this Phase 1 study in conjunction with the potential BRWTF treatment alternatives. • Further define the scope and cost of source water and treatment alternatives as necessary to perform final evaluation. • Develop recommended long-term plan and prioritize implementation of key elements. • Perform utility cash flow scenarios and develop a capital improvements program based on projected financial conditions. • Develop facility planning documents as required to guide the implementation of improvements for both the BRWTF source water supply and treatment facilities. 4.6 City of Boulder Zone 1 Distribution System Analysis (2003) This report investigated the impacts to Zone 1 of the City of Boulder treated water transmission system resulting from expanding the capacity of the BRWTF from 11.5 to 20 MGD (peak hour flows). A hydraulic analysis was performed to determine the system's ability to accommodate the additional flow and identify needed improvements. The analysis focused on the following areas: • High headloss in the Zone 1 transmission mains and resulting low pressures. • Pumping capacity at the BRWTF high service pump station. • Pumping capacity at the Zone 1 Pump Stations (Cherryvale PS and Iris PS). • Storage capacity in Zone 1. The modeling effort focused on evaluating the system's ability to meet major performance criteria, including: • Minimum dynamic pressure • Minimum emergency pressure • Minimum pressure along Airport Road • Maximum acceptable velocity • Average day demand • Low day and peak hour demand Several different demand scenarios were evaluated, chosen to simulate the desired higher rates of production from the BRWTF and corresponding lower production rates from the BWTF. Each scenario consisted of flows from both WTFs, demand by zone, total system demand, and pumping requirements from Zone 1 to Zone 2 pump stations. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-6 Three of the four scenarios evaluated represented controlling scenarios for certain factors. The Low Demand scenario resulted in the highest Zone 1 to 2 pumping, the Average Summer Day scenario was a controlling scenario for pump selection, and the Peak Hour scenario was used to determine additional pumping requirements at the BRWTF High Service Pump Station (HSPS). The report goes on to detail the distribution system evaluation, which was split into a pipeline evaluation and a pump station evaluation. The pipeline evaluation presented three alternatives for pipeline construction based on maintaining acceptable pressures and minimizing cost. Costs were presented and Alternative 1 was recommended. Pump station evaluation included a SCADA data evaluation to ensure that the actual pumps performed as indicated by the curves given in the model, and a modeling evaluation to determine if the existing pumps were adequately sized to handle the new conditions. Detailed results of the evaluation can be found in the original report. The evaluations found that the following additional equipment was recommended: • BRWTF HSPS: two additional pumps, similar to the capacity of the existing pumps. • Cherryvale Pump Station: Refurbish the entire facility, including three existing pumps and VFD's, PRV's of varying sizes, flow meters, pressure sensing equipment, and expansion to the existing building to increase electrical equipment capacity. • Iris Pump Station: Refurbish the entire facility, including three new 200 HP pumps and VFD's, PRV's of varying sizes, flow meters, associated pipe and appurtenances, and a new building adjacent to the existing structure. The City was considering constructing a new storage tank near the Cherryvale pump station and requested an evaluation of Zone 1 storage capacity. The report found that Zone 1 storage was deficient by nearly 2.0 MGD, but also that Zones 2 and 3 had an excess storage volume of 11.7 MGD each. Since Zones 2 and 3 are at higher elevations than Zone 1, their excess storage can feed Zone 1 by gravity. The report concluded that Zone 1 storage was sufficient. In conclusion, the report found that the Zone 1 distribution system could not handle the proposed increase in production at the BRWTF without significant improvements, which included approximately 18,800 linear feet of parallel pipe in the Diagonal Highway right-of-way (ROW), and increased pumping capacity at all of the Zone 1 pump stations. The estimated total cost for all of the above improvements ranged from $5.7 million to $7.0 million. The report concludes with a detailed discussion of project budgeting and construction phasing. 4.7 Betasso Water Treatment Plant Facility Improvement Plan (2005) This report evaluates and recommends improvements needed for the BWTF to provide safe working conditions, improve the reliability of the water treatment process for public health, comply with new safe drinking water act regulations and extend the life of the plant. The improvement plan evaluated the capacity and performance of each of the unit processes and residual handling facilities based on water demand, regulatory requirements, and internal City water quality goals. This information was then used as the basis for process alternative identification, evaluation, and selection. Improvements were categorized as near-term, mid-term, and long-term and prioritized based on a range of categories. In summary, the recommended improvements are as follows: City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-7 Near-term improvements included: • Contract residuals dewatering support facilities • Add residuals drying pad • Improvements to the south lagoons • Sand replacement for the north lagoon • Pump diffusion flash mixing • C02 improvements for pH control • PACL improvements for coagulation Mid-term Improvements included: • Flocculation/Sedimentation Improvements, including > Inlet baffle > Serpentine baffles > Flocculation Equipment Modifications > Flocculation aid polymer addition > Flocculation to sedimentation baffles > Sedimentation effluent weirs • Modifications of north lagoon, including north engineered sand drying beds • DAF or Plate Settlers • Clearwell No. 2 baffle wall Potential long-term improvements include: • UV disinfection (if raw water quality degrades) • Membranes, or • Filter media replacement 4.8 Integrated Evaluation of the BRWTP Source Water Protection and Treatment Improvements Study (Integrated Study) (2007) The Integrated Study was performed within the context of an ongoing effort by the City of Boulder to establish definitive drinking water quality and quantity goals as a framework for planning and implementing future improvements throughout the City's drinking water system. One central strategy for achieving the City's water quality goals is to implement a multi-barrier approach to protecting the City's drinking water supply from biological and chemical contaminants. These barriers may include source water protection measures that either reduce or prevent introduction of contaminants or minimize their passage throughout the drinking water system through treatment. Raw water is conveyed to the BRWTF from Carter Lake through a 21-mile long, open, earthen canal, referred to as the Boulder Feed Canal, which ultimately discharges into Boulder Reservoir. Between April and October, the City diverts raw water from the BFC just upstream of Boulder Reservoir, and delivers it through a pipeline directly to BRWTF. During the remaining months, when BFC is not in operation, raw water is pumped from the Boulder Reservoir to BRWTF for treatment. Both BFC and Boulder Reservoir have several features that make them vulnerable to source water quality degradation. This study included a review and extensive analysis of existing historical, biological, physical and chemical water quality data of raw water sources, including Carter Lake, BFC, and Boulder Reservoir. Based on this evaluation, it was determined that Carter Lake has superior overall water quality as a raw City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-8 water source when compared to BFC and Boulder Reservoir. Of particular concern are the introduction of chemical contaminants and pathogenic microorganisms during raw water conveyance through BFC and storage in Boulder Reservoir, as well as increased salt content due to dissolution of naturally occurring minerals in Boulder Reservoir sediments. Also of concern are objectionable tastes and odors that result from seasonal algal blooms and increased manganese levels due to oxygen depletion in Boulder Reservoir. Carter Lake is much less susceptible to these types of water quality degradation because of its surrounding topography and protection of water sources- This study states that it is believed that the water quality of Carter Lake will continue to be suitable as a water source for BRWTF for decades to come. Although the BRWTF currently and is expected in the future meet or exceed all National regulatory requirements, finished water quality is vulnerable to short-term degradation due to seasonal variation in Boulder Reservoir and acute contamination episodes either in the BFC or the Boulder Reservoir. Finished water quality is vulnerable to: • Source water microbial contamination in both the BFC and Boulder Reservoir • Source water contamination by organic micropollutants in both the BFC and Boulder Reservoir • Source water variation in Boulder Reservoir resulting in taste and odor problems and manganese uptake • Treated water disinfection byproduct formation • Non-uniform concentrations of TDS and sulfate across the distribution system when Boulder Reservoir is used. As part of the evaluation of the multibarrier alternatives, the Kepner-Tregoe® (K-T®) decision analysis procedure was used to evaluate six alternatives. They were screened for applicability based on several factors, including integration with the existing treatment process train, probable performance, and economic considerations. Potential conceptual improvements were evaluated based on their ability to address one or more of the contaminant barriers identified including microbial pathogens, DBPs, organic micropollutants, manganese, taste and odor, TDS, and sulfate. Greater consideration was given to alternatives that addressed more than one contaminant barrier. The six alternatives ranged from improved treatment, using anything from UV disinfection, GAC adsorption, or ozone oxidation, to installing a pipeline directly from Carter Lake to feed the BRWTF. The preferred solution was the following: Alternative 6. Carter Lake pipeline for turbidity, suspended solids, manganese, taste and odor, organics, DBP, and inorganics control followed by chlorine dioxide preoxidation for additional pathogen taste and odor, organics. and DBP control. This preferred alternative meets all of the City's water quality goals, and provides at least one barrier for each contaminant category evaluated. Its noneconomic performance score was 0.942 while the other alternatives clustered between 0.5 and 0.6. The estimated life cycle costs of all of the alternatives ranged from $5.2 million to $53.4 million, while the preferred alternative was estimated to have a net present value of $17.1 million. This alternative was selected because it had a number of compelling benefits that are not provided by the other alternatives, including: • It treats the best available water source with the simplest and most robust combination of processes. • Has the best non-economic performance by satisfying 22 of 28 criteria evaluated as well or better than other alternatives. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-9 • It alone addresses the near and long term potential for continued degradation of water quality in existing BRWTF sources due to continued residential development, extensive agricultural land use, and increasing recreational use. Preventing source water contamination provides a more robust barrier than subsequent treatment as the first line of defense in protecting public health. • Other regional drinking water providers also desire to use a dedicated pipeline from Carter Lake for raw water delivery to their facilities. Combining raw water conveyance to BRWTF with that of other providers allows more efficient use of scarce regional water resources. • Full containment of raw water conveyance from Carter Lake to BRWTF would provide additional flexibility in managing the City's water resources portfolio. Other water delivery alternatives require seasonal storage of raw water in Boulder Reservoir for use when BFC is not in service. Year-round storage in Carter Lake would remove the need to project annual seasonal storage required in Boulder Reservoir, and thus avoid the undesirable consequences that result if seasonal Boulder Reservoir storage is substantially overestimated. • Conveyance of raw water through a Carter Lake pipeline would be consistent with the City's historical policy of protecting source water quality by providing full containment from its other water sources. • Full containment from Carter Lake to BRWTF would provide a much more uniform raw water quality, substantially simplifying treatment optimization and increasing treatment process reliability. • This alternative is the only BRWTF water delivery approach that provides at least one robust barrier for each contaminant category considered in this study. 4.9 AWWA Peer Review Report; 2008 The AWWA Peer Review Report, prepared by QualServeTM for the City of Boulder is a report that was compiled by a team of utility peers. The purpose of the report was to identify areas of strength and opportunities for improvement. The Peer Review team provided specific strengths and opportunities for improvement in the following categories: • Leadership and Organization • Customer Strategy and Satisfaction • Human Resources Management • Customer Accounts Management • Continuous Improvement • Government, Business, and Community Relations • Health and Safety Management • Collection System O&M • Emergency Planning and Response • Wastewater Treatment O&M • Capital Improvement Program • Industrial Pretreatment Program • Strategic Planning • Biosolids Management • Finance and Fiscal Management • Permitting/Air and Water Quality • Plant and Property Management • Water Resources and Watershed Management • Purchasing • Water Treatment O&M • Information management • Water Distribution O&M • Engineering • Drinking Water Quality Management • Customer Service City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-10 The overall key findings of the Peer Review Team, as taken directly from the report, are: • Strengths > The Staff in all the work groups are dedicated, competent, and caring employees. > The Utility is very proactive in several work groups on regulating and legislative issues- > The development and prioritization of the capital improvements program is excellent. > Proactive maintenance and cleaning program in collection system. > Data management and training/safety programs at wastewater plant. > Well run industrial pretreatment program. > Process for review, approval, and construction of developer projects provide excellent seamless service for those customers. > Good overall purchasing program that provides ease and flexibility for purchasing by personnel. > Customer service representatives and meter readers are highly motivated and provide efficient and effective customer service. > Supportive and articulate workforce that seems to truly appreciate the coworkers. > Clean well kept facilities and equipment. > Employees have passion for protection of the Utility's natural resources. • Opportunities for Improvement > Work toward de-compartmentalization of the work groups. Cross training and working across work groups lines will help the Utility be more unified. > Management and accounts payable staff should review purchases through the "informal process" to insure that actual quotes are being received and documented. > Integration of workgroups within the Utility. > Continued expansion of GIS integration to improve work systems. > Establish a vision, values and goals to guide employees in improving the Utility's performance. > Produce as-built drawings in a timelier manner so GIS maps can be accurately updated with new facilities. This will provide the information to field crews which will allow them to work more efficiently. > Implement E-care to provide customers on-line access to their accounts and insure the IVR system provides information for the correct customer. > Strive to improve vertical communication and establish and encourage horizontal communication. > The attempt by management to not "micro-manage" has resulted in a separation between management and the rank and file where management is seen as lacking leadership and being indifferent. A closer relationship and better understanding between groups needs to be developed. Staffing philosophy differs from utility to utility. Boulder should decide if it is best to staff for (or almost all) needs, or staff for a base level and employ contractors, consultants, and others for needs above the established base. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-11 4.10 City of Boulder Water Conservation Plan (2009) The following summary is an excerpt directly from the Water Conservation Plan, written by the City of Boulder in 2009: Conservation has long been an important component of the City of Boulder's (the city's) water management strategy, including outreach, education, and technical assistance programs that date back over 20 years. The purpose of this Water Conservation Plan is to provide guidance in updating and implementing the city's Water Conservation Program in a way that is compatible with the city's water supply system, existing conservation programs, water resources management strategy, and values of the community. The city provides potable water to approximately 113,000 residents in its service area, which encompasses a total of just under 26 square miles. The city's total annual treated water demand is approximately 18,600 acre-feet (2007 demand), primarily supplied by surface water withdrawn from Boulder Creek, and secondarily from the Colorado-Big Thompson and Windy Gap Projects on the western slope. Residential single-family users make up most of the 28,500 connections in the service area. Across all sectors, citywide annual demand per connection totaled approximately 213,000 gallons in 2007. The city's total daily per capita water use has varied from year to year, from a low of 148 gallons per capita per day (gpcd) in 2004 and 2007 to a high of 209 gpcd in 1988. Since the adoption of the city's comprehensive conservation program following completion of the Water Conservation Futures Study in 1999, per capita water use has significantly declined, particularly from the severe drought year of 2002 to present. The City of Boulder is approximately 90 percent built out and any additional improvements or additions to its water system will focus more on improving system operating flexibility than increasing capacity. In 2007, water revenues totaled over $19,385,000 for all customer classes in Boulder. Single family residential customers contributed approximately 40 percent of revenues, followed by commercial and industrial users (26 percent), and finally multifamily residential and sprinkler users (19 and 15 percent). As of 2007, the city has used a five-block rate structure based on established "water budgets" for each type of customer, an important component of the city's overall water conservation strategy. In 1999, the city completed its Water Conservation Futures Study to examine existing water use patterns and recent trends, update future water demand projections and reliable supply capability, and reassess the role of water conservation programs in helping to meet the city's needs. The Water Conservation Futures Study led to the adoption of a Comprehensive Conservation Scenario to aggressively manage and conserve water. The study was followed in 2000 by the Treated Water Master Plan, which provides guidance for improvements to the city's water system. In 2003, a Drought Response Plan was developed that established water use reduction measures to be implemented in the event of a severe drought that would quickly, but temporarily, greatly reduce water demands during the critical drought period. The drought response measures work in concert with, but are separate from, the city's on-going water conservation efforts. In April 2009 the Source Water Master Plan was completed, and the Water Quality Strategic Plan was finalized in June 2009. Both plans address water conservation, to some degree. An update of the Drought Response Plan was initiated in early 2009. Volume I will be completed in the fall of 2009 and the update of Volume II will be completed in 2010. Today, the city operates a wide range of conservation programs that address both indoor and outdoor water use, as well as a variety of customer categories. City Council has adopted a comprehensive water conservation program for the city to achieve an overall reduction of water use at build-out. Implementation of the city's goal has been accomplished through an extensive water conservation program that continues City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-12 to develop. Achievement of these targets will result in an expected overall reduction in total demand in the range of 19 percent at build-out as compared to water use at build-out absent a Water Conservation Program. Per capita water use at build-out may be greater than 2007 levels due to increases in the population to jobs ratio but will be less than without the Water Conservation Program. As its Water Conservation Program has evolved, the city has developed a number of criteria to screen both existing programs and potential new programs. These criteria, along with ongoing and potential new conservation programs, will be integrated into modifying forecasts as part of an update of the 2000 Treated Water Master Plan, which the city anticipates will take place in the next couple of years. Completion and approval by the Colorado Water Conservation Board of this Water Conservation Plan is anticipated to occur by fall 2009. Monitoring of the city's water conservation progress will be carried out in a variety of ways, including but not limited to the tracking of billing system data, daily water and wastewater treatment and production, daily operations of the city's surface water supply system, annual program costs, number of rebates, and feedback from the public. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 4-13 5 Facilities Evaluation The City's existing water treatment and distribution facilities were described in Section 2. This chapter provides an evaluation of those facilities to determine specific areas where improvements are needed. 5.1 Water Treatment Plants The City's two water treatment plants were evaluated to establish their ability to consistently produce high quality finished water that exceeds all regulatory requirements and drinking water industry standards for public health protection. Each unit process was analyzed on the basis of standard design criteria to determine its performance potential. These results were combined with operating data and information gathered during plant inspection tours and interviews with plant operations staff- To establish a basis for current treatment capacity, the various treatment process elements have been analyzed for their capability to treat the raw water typical for that facility to meet regulatory requirements and City standards, with consideration given to in-progress improvements- The operations staff at the BWTF reports the following challenges in operating the facility and producing treated water: • The pumped-diffusion rapid mixer is ineffective at dispersing the applied chemicals. • At flows in excess of 30 to 35 MGD, the pretreatment is inadequate to sustain effective treatment. • During periods of high concentrations of color and total organic carbon in the source water, the filters are limited in run time by a breakthrough in turbidity. • The residuals thickening, dewatering, and drying processes are insufficient to treat the dilute concentration of the solids. Plant operations staff has managed through the challenges by shifting water production to the BRWTF when needed. In an effort to resolve the challenges, an evaluation of water quality and operations records from 2004 through 2009 as well as current documentation of the operation of the facility was performed. The data was reviewed to determine trends and potential areas for improvements in plant performance. 5.1.1.1 Source Water Flows and Turbidity A summary of the flows from the two supply sources, Lakewood and Barker Reservoirs, is presented in Figure 5-6. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-1 5 BWTF Historical Flow Data - 2004-2009 40.0 35.0 30.0 25.0 -a ao 20.0 0°1 L _o U. 15.0 ~ jq' - - - 10.0 - - I I ~ j 5.0 I l 0.0 ■ Total Flow MGD Lakewood Flow MGD Avg ■ Barker Flow MGD Avg A review of the information in Figure 5-6 reveals: • The maximum flow to the BWTF is below the stated 50 MGD capacity of the facility. • Throughout the year, water is withdrawn from the two sources individually or combined to meet the demands. Most of the flow comes from the Lakewood Reservoir. • There is a distinct seasonal variation in flow with the minimum flow at approximately 7 MGD and the maximum flow at approximately 30 MGD. To characterize the water quality of the two sources, an evaluation of the turbidity and color constituents was performed. The results of the analyses are shown in Figures 5-7and 5-8. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-2 BWTF Source Water Turbidity - 2004-2009 7.00 6.00 • • 5.00 • • Z 4.00 • ~ • ♦ • T ~ • 3.00 • 2.00 ♦ • ♦ N 1.00 • • 0.00 9/1/02 1/14/04 5/28/05 10/10/06 2/22/08 7/6/09 11/18/10 ® Barker Raw Turbidity • Lakewood Raw Turbidity The following observations can be made regarding turbidity in the source water. • There is a seasonal variation in turbidity with Barker Reservoir generally having higher turbidities than Lakewood Reservoir. • The variation in the turbidity of Barker Reservoir is more erratic than the Lakewood Reservoir. • Peak turbidities occur in the spring and summer and are probably associated with spring runoff and snow melt. • Turbidities are generally less than 5 NTU, and average between 1 to 2 NTU_ More diagrams summarizing the evaluations of turbidity appear in Appendix B. The results of the analysis of the concentration of color in the source and finished water are shown in Figure 5-8. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-3 Fig,,. i-o 7-2: BWTF Source Water Color vs. Finished Color "o 14 100 • 12 80 ' • ■ • - 10 • `2 u : Note: Flow and Color • o Data are missing for v a, January-June 2007 • " • $ 60 j ■ 3 i• + • v u ■ • • • t `p P.m • . r 40 1L ■ ■ .t1 • • ■ - 4 20 ■ ■ ■ ■ p rte- •~~rrrrt i- -rir-Y■Y-■~■ r -rr■u---•-- --0 9/1/02 1/14/04 5/28/05 10/10/06 2/22/08 7/6/09 11/18/10 Barker Color • Lakewood Color • Finished Water Color Regarding color in the source and finished water, the following should be noted: • Lakewood Reservoir has the highest concentration of color of the two sources of supply. • There is a correlation between color in the finished water and color in the source water, as expected. • A seasonal variation in the concentration of color exists with the peaks occurring in the spring and summer. Additional diagrams presenting the results of the evaluations of the color are shown in Appendix B. 5.1.1.2 Pumped-Diffusion Mixing Plant staff has indicated dissatisfaction with the performance of the existing pumped diffusion flash mixing system, installed in 2007. An investigation of the existing system was performed to determine the likeliest cause of these complaints. The flash mix pump, PMP-22-0201, was selected to deliver 800 gpm at 30.3 ft TDH. The maximum plant flow rate is 46 MGD, or 31,944 gpm. Therefore, the flash mix pump was designed to deliver 2.5% of the maximum plant flow rate, which is in line with the recommended 2-5% of plant flow rate recommended in Section 32.3 of Integrated Design of Water Treatment Facilities, Kawamura 1991. However, the outlet nozzle for the flash mixer system outputs 800 gpm at 7 psi, or 16.2 ft of head. Assuming a conservative 2 ft of friction and minor losses in the suction and discharge piping, a total of 182 feet of headloss is produced at 800 gpm, which is well below the selected pump curve. Estimates indicate that the actual pump output is roughly 950 gpm, or 3% of the maximum plant flow, which is still within the recommended limits. Performance degradation likely occurs when plant flow is significantly less than the maximum. The flash mix pump was installed without a VFD or motorized throttling valves, meaning that pump capacity is fixed at approximately 950 gpm, regardless of plant flow. As a result, at the minimum plant flow of 8 MGD, or City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-4 5,555 gpm, the flash mix system delivers 17% of the plant flow rate, several times higher than the recommended range. 5.1.1.3 Flocculation/Sedimentation The flocculation process is rated on the basis of available detention time and mixing energy, the number of mixing stages and capability for adjusting the mixing energy to optimize the process and provide tapered mixing energy. At the BWTF, flocculation and sedimentation occur in successive sections of common basins. Each flocculation zone is approximately 80 feet wide by 36 feet long by 10 feet deep. Water enters the flocculation zone through a ported wall that promotes uniform distribution of flow. Each flocculation zone has three horizontal-paddle-wheel type mixers. The mixers are driven by variable speed drives to allow the mixing energy in each stage to be varied for best performance and provide for tapered mixing which reduces the mixing energy in each successive stage to promote the progressive formation of large floc. The flocculator drives of basins one and two have the original mechanical speed controls. These are worn, making it difficult to make precise adjustments. The mechanical speed controllers on the basin three and four flocculators have been replaced with adjustable-frequency drives. This type of drive makes it easy to change flocculator speeds and make precise adjustments to the mixing energy in each stage. Flocculation process facilities are rated based on the available detention time provided, with allowances made for the quality of flow control and mixing provided. Typically, a detention time of 20 to 30 minutes is considered adequate. At a flow rate of 50 MGD, the Betasso basins would provide a detention time of 25 minutes, midway in the typical range, which would normally provide adequate performance. However, the baffles that divide the flocculation zone into stages only extend from the ceiling to about half-depth in the basin. This arrangement does not provide three true mixing stages. Flow through the process is encouraged to short circuit along the floor of the basin resulting in shorter effective detention time and reduced floc particle interaction. This potential for short-circuiting is further promoted by the location of the ports through which the flow enters the basin. The ports are centered on a line approximately the same height above the floor as the centerline of the flocculator paddle wheels and in line with the bottom edge of the baffles. Thus, currents can be induced in the lower portion of the flocculation zone that would pass under the baffles and carry through into the sedimentation zone. This non-ideal flow pattern results in a net reduction in the rate at which water can be effectively flocculated. If the minimum allowable detention time were set at 30 minutes the rated capacity of the flocculation process would be only 42 MGD. In fact, with the existing baffle arrangement a detention time of more than 30 minutes may be needed for optimum flocculation resulting in a further reduction in capacity. Based on available detention time, the existing flocculation basins have adequate volume to treat 50 MGD. However, the existing baffle arrangement results in a substantial capacity reduction. To achieve the desired capacity it would be necessary to modify the baffles to establish a controlled, uniform flow pattern and create three distinct flocculation zones. Replacing the worn mechanical speed controllers of basins one and two with adjustable frequency drives to facilitate mixing energy adjustment would also be needed to attain optimum process performance and reliability. Although definitive testing has not been done to prove it, there is some evidence to suggest that flocculation may be impaired during certain times of the year due to low particle density. When this condition exists, the low-particle density will result in too little particle interaction in order to form settleable floc, thus resulting in reduced removal efficiency. In essence, the raw water is too clean to be effectively treated by conventional processes. Additional testing would be needed to determine whether this particle limitation condition is actually operative at Betasso and if so whether it poses a potential health threat from pathogens passing through the process. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-5 To assess recent performance of the flocculation and sedimentation process analysis of the settled water turbidity under average and challenge conditions for the years 2004-2009 was conducted. A diagram presenting the performance of the four flocculation/sedimentation basins under average conditions is shown in Figure 5-9. -~WTF Settled Water Turbidity - 2004-2009 2.00 1.80 _ 1.60 1.40 • • 1.20 • 1.00 i > ♦ 0.80 0.60 'r -g' • Y' ` 3 r t E.•:, 0.40 0.20 ® • 0.00 ; t - , c a 9/1/02 1/14/04 5/28/05 10/10/06 2/22/08 7/6/09 11/18/10 Basin #1 Settled Turbidity ♦ Basin #2 Settled Turbidity o Basin #3 Settled Turbidity Basin #4 Settled Turbidity As shown above, average settled water turbidities are less than 1 NTU. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-6 It is also important to evaluate the performance of the basins under challenging conditions such as high flows, and high raw water turbidities and color. The performance of the basins under challenge conditions, which include a plant flow in excess of 24 MGD, a turbidity of greater than 4 NTU in either supply source, and a high concentration of color are shown in Figures 5-10, 5-11, 5-12 and 5-13 for comparison. 0: BWTF High Flow Days 24 I IGD) Settled Water Turbidity 1.60 1.40 1.20 .00 X7.80 :5 he L J 3 r X0.60 - 0.40 0.20 - -Basin #1 Ave turbidity fBasin #2 Ave Turbidity Basin #3 Ave Turbidity -0FBasin #4 Ave Turbidity City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-7 Figure 5-11: BWTF Barker High Turbidity Days 4 NTU) Settled and Raw Water A)m-rune Turbidity 1.6 12.00 1.4 - 10.00 1.2 Z 8.00 f- 1 z L L 0.8 - - l ¢y, - 6.00 F uH~ L 41 m f ,Y a o 0.6 3 4.00 m v 0.4 2.00 0.2 0 0.00 -41-Basin #1 Basin #2 -0-Basin #3 = Basin #4 tRaw Water City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-8 Figur BWTF Lakewood High Turbidity Days 4 NTU) Settled and Raw WatAr Aver in'-, Turbidity 1.40 - 20.00 18.00 1.20 16.00 1.00 14.00 j z z - 12.00 0.80 ' v L F- 10.00 7 G1 L 0.60 8.00 3 a, 3 0.40 6.00 4.00 0.20 2.00 0.00 0.00 tBasin #1 Basin #2 -0<-Basin #3 =Basin #4 -t-Raw Water City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-9 s. 7-1 BWTF Source Water Color and Settled Turbidity 60 Note: Color Data is missing for 1.40 January-June 2007 50 - ■ ■ ■ 1.20 ao E ■ 3 40 - 1.00 o ■ M z fO ■ 0.80 a 30 ■ 2' co 0.60 ~ s D 20 ■ ■ L M O • • ■ N ■ 0.40 10 - - ' A 0 *00, .0 - 0.20 ■ • ■ • A • i ■ ■ ■ ' i~ ■ ■ ■ u ■ ■ ■ era; ■ 0.00 0 3/24/06 10/10/06 4/28/07 11/14/07 6/1/08 12/18/08 7/6/09 1/22/10 8/10/10 • Barker-Color ■ Lakewood - Color Finished - Color Basin #1 Settled Turbidity Basin #2 Settled Turbidity Basin #3 Settled Turbidity Basin #4 Settled Turbidity 1 Week Mov. Ave (Basin #1 Settled Turbidity 1 Week Mov. Ave. (Basin #2 Settled Turbidity) 1 Week Mov. Ave. (Basin #3 Settled Turbidity) 1 Week Mov. Ave. (Basin #4 Settled Turbidity) City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-10 Under challenge conditions such as high plant flows and high turbidities in the source water, Basins 3 and 4 outperform Basins 1 and 2, Basin 2 outperforms Basin 1, Basin 3 generally has the best performance, and Basin 1 is consistently the worst performer. The settled water turbidity is less than 2 NTU and averages about 1 NTU during the challenging conditions. It is important to note that these values are in line with conservative industry standards for sedimentation basin performance. There is no apparent correlation between high color in the raw water and settled water turbidity. Treating waters with high color does not appear to adversely affect the performance of the flocculation/sedimentation process. Appendix B presents additional evaluations of settled water turbidity. The concentration of settled solids being removed from the sedimentation basins is reported to be less than 0.5%. With an average turbidity of 1 to 2 NTU for the raw water, there are not a lot of solids to remove and the dilute solids concentration of the settled solids reflect this condition. 5.1.1.4 Filtration Indicators of filter performance include the turbidity and particle count of the filtered water and the unit filter run volume (UFRV)_ A summary of the evaluation of the filtered water turbidity and the UFRV is presented in the following sections. A plot of the average filtered water turbidity versus rate of filtration is presented in Figure 5-14. 0.5 0.45 0.4 0.35 7 F Z 0.3 '6 ♦ 0.25 H N 0.2 > 4 0.15 X 0.1 i' X. 0.05 IN I-AV o :x ♦ xXg, 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 Rate of Filtration (gpm/ft2) ♦ Filter 1 ■ Filter 2 Filter 3 X Filter 4 A: Filter 5 Filter 6 Filter 7 Filter 8 In reviewing the information in Figure 5-18 it is noted that the average turbidity at all filtration rates is about 0.03 NTU with a maximum typically less than 0.1 NTU. Filter performance is therefore independent of the rate of filtration for rates up to 5 gpm/fe. It is significant to note that the filters are managed to remove a filter from service once the filtered water turbidity exceeds 0.1 NTU so it is expected that the turbidity values will be consistently less than 0.1 NTU. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-11 An evaluation of the average filter turbidity at plant flows greater than 24 MGD is shown in Figure 5-15. 0.10 0.09 0.08 0.07 z 0.06 X ~ # X A* ~ 0.05 VA)PK + X w m 0.04 lip 0.03 ♦ x5 0.02 . L ~Xx~x N • MI ~ X 0.01 ♦ Filter 1 ■ Filter 2 Filter 3 X Filter 4 X Filter 5 Filter 6 Filter 7 Filter 8 Under challenge conditions of high plant flow 24 MGD), the performance of the filters does not degrade. This again can be explained in part by the method in which the filter operation is managed, at filter breakthrough of 0.1 NTU as opposed to allowing the filter run to continue and produce higher turbidities. Additional figures presenting the results of other analysis such as rate of filtration versus maximum filter turbidity and individual filter performance during spring runoff are shown in the Appendix B. A plot of the trend lines for the one-week moving average of unit filter run volumes (UFRV) is shown in Figure 5-16. It is important to note that the trend lines are one week moving averages so the UFRVs of the individual filter runs are considerably lower. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-12 7-1^ RWTF Historical UFRV Data Trendlines Only- One Week Moving Averages 12,000 11,000 10,000 - Cr H m 9,000 v E 3 8,000 - c r' 7,000 - LL 6,000 5,000 - 4,000 - 3/24/2006 10/10/2006 4/28/2007 11/14/2007 6/1/2008 12/18/2008 7/6/2009 1/22/2010 8/10/2010 Filter 1 Filter 2 Filter 3 Filter 4 Filter 5 Filter 6 Filter 7 Filter 8 1 Week Mov. Avg. (Filter 1) 1 Week Mov. Avg. (Filter 2) 1 Week Mov. Avg. (Filter 3) 1 Week Mov. Avg. (Filter 4) 1 Week Mov. Avg. (Filter 5) 1 Week Mov. Avg. (Filter 6) 1 Week Mov. Avg. (Filter 7) 1 Week Mov. Avg. (Filter 8) City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-13 The diagram shows seasonal variation in the UFRV with a distinct and significant decrease in performance in the spring/summer of the year. The sharp decrease in the one-week moving average UFRV takes place over a time frame of about three months each year, coincident with the spring runoff. The seasonal decrease in the UFRV results in a loss of a production of approximately 400 MG/yr of finished water based on one-week moving averages of UFRV's. The cause of the seasonal decrease in UFRV was investigated. The comparison includes an evaluation of the individual filter performance as well as a comparison of changes of filter performance against changes in source water quality. The evaluation of the individual filter performance revealed a difference in the performance of filter banks. Filters 1 through 4 were constructed together and comprised one bank. An expansion of the BWTF was made with the addition of Filters 5 through 8, which make up the second bank. In addition, it is likely that filters 1-4 were most affected by the previous air entrainment issues in the source water supply. It is suspected that the finer media in the filters was removed. The air entrainment problem has now been resolved. There also may be an unequal flow split to the basins that should be evaluated. The performance of Filters 1 through 4 and 5 through 8 are shown in Figures 5-17 and 5-18, respectively. In comparing the information in the two figures, it is noted that Filters 1 through 4 exhibit a more severe seasonal depression in UFRV than Filters 5 through 8. When filter performance was compared against water quality in the source water, a correlation between the concentration of color in the source water and a decrease in the filter UFRV is observed. A presentation of this correlation is shown in Figure 5-19. This observance is consistent with the operations staff reported problems of turbidity breakthrough while treating waters with a high color concentration. An explanation for the decrease in UFRV is the change in floc characteristics associated with removing dissolved constituents as opposed to removing particulate that is associated with turbidity. The change in the floc can change its filterability characteristics. During conditions of high color in the water supplies, an average UFRV of 7,200 gal/ft2 is assumed. A filter run time of approximately 25 hours is estimated at a filtration rate of 4.7 gpm/sf. A filter run time of 25 hours will require the filter to be washed on the order of once a day. Based on site observations and operations staff input, rehabilitation of the filter gallery including valve and actuator replacement and repainting of the gallery piping is needed. The City of Boulder has performed some experiments on filters at BWTP. The findings are presented in the following documents; Filter Run Time and Analysis Report Betasso Water Treatment Plant dated July 27, 2009, and Filter #2 Surveillance and Evaluation Report Betasso Water Treatment Plant dated November 20, 2008. MWH reviewed these reports and can offer the following comments. • The shorter filter runs for filters 1-4 is clear evidence that either the media itself or the washing of the media is not ideal. • The "eruptions" noted in the first report may or may not indicate that the underdrains or gravel layer are damaged. The findings in the second report show the media is dirty even after washing, so the eruptions may be from uneven or inefficient media cleaning. Damage to underdrains or disruption of the gravel layer typically results in premature turbidity breakthrough during the filter run, and this has not been reported. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-14 • The media coring shows dirt accumulation in the upper reaches of the bed; a symptom of the media loss noted in the report. With this much media loss, the bed never expands into the surface washing zone to receive the additional agitation. • The report discusses the duration of the wash, but does not describe the sequence of surface and backwashing. This is something that should be investigated after the media is restored to proper depth. The two need to overlap for a minute or two, usually with the surface wash starting fi rst. • If continued floc retention monitoring shows the media is still not getting clean, the refurbishment of the surface wash system should be considered. Depending on condition, replacement with an alternative surface wash design or an air scour design may be needed. • Also, it appears that the media in filters 1-4 is mismatched in size, promoting intermixing at the interface between the coal and sand. This increases headloss, shortens filter runs, and contributes to dirt retention in this region. If restoring the media depth and adjustments to the wash sequence do not work to lengthen the filter runs, complete replacement of filter media may be required. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-15 7,17: RWTF Historical UFRV Data - Filters 1-4 Only 12,000 X Aj 11,000 ♦ X ~X 10,000 • X X ♦ ♦A ♦ ♦ ♦ x x 9,000 X X X o ® ♦ Ole x v • E 8,000 X > XX ■ ■ x LL 7,000 11&;~- : ■ ■ 6,000 *X ■ ~ ~ ~ X* X 5,000 r,. 4,000 - ® - - 3/24/2006 10/10/2006 4/28/2007 11/14/2007 6/1/2008 12/18/2008 7/6/2009 1/22/2010 8/10/2010 Filter 1 ■ Filter 2 Filter 3 X Filter 4 1 Week Mov. Avg. (Filter 1) 1 Week Mov. Avg. (Filter 2) 1 Week Mov. Avg. (Filter 3) 1 Week Mov. Avg. (Filter 4) City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-16 - RWTF Historical UFRV Data - Filters 5-8 Only 13,000 12,000 +)K X • )K 11,000 - % + 10,000 Cr m ao E 9,000 - 3 - 0 c ~ 8,000 x ;K X c 7,000 I- X 4. + • • " + x • 6,000 ya 5,000 + + 4,000 3/24/2006 10/10/2006 4/28/2007 11/14/2007 6/1/2008 12/18/2008 7/6/2009 1/22/2010 8/10/2010 Filter 5 Filter 6 Filter 7 Filter 8 1 Week Mov. Avg. (Filter 5) 1 Week Mov. Avg. (Filter 6) 1 Week Mov. Avg. (Filter 7) 1 Week Mov. Avg. (Filter 8) City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-17 s. is BWTF Historical Source Water, Finished Water Color and UFRV 60 11,000 ■ ■ ■ 50 ` 10,000 ■ r M 0 IM Note: Flow and ■ - 9,000 Color Data are a 40 -i missing for January ■ ■ , o ■ ■ m ■ ■ 8,000 a c ■ E 30 - - ' 2 o u 7,000 3 L L.: 20 ■ ii ' Y . 6,000 c D 10 ■ ■ . ■ ■ • M ■ 5,000 An Elf A A ■ j ■ ■ ■ ■ • ■ ■ ■ • 0 ■ ICY - 4,000 3/24/06 10/10/06 4/28/07 11/14/07 6/1/08 12/18/08 7/6/09 1/22/10 8/10/10 • Barker-Color ■ Lakewood - Color Finished - Color Filter 1 UFRV Filter 2 UFRV Filter 3 UFRV Filter 4 UFRV 1 Week Mov. Ave (Filter 1 UFRV 1 Week Mov. Ave. (Filter 2 UFRV) 1 Week Mov. Ave. (Filter 3 UFRV) 1 Week Mov. Ave. (Filter 4 UFRV) City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-18 5.1.1.5 Filter Backwash System and Backwash Water Supply System The surface wash system at BWTP is older, and if replacements are being made to the filters, it is recommended that the surface wash system is also upgraded at that point in time. The filter backwash water supply system is comprised of two 972 gpm pumps to fill a 200,000 gallon tank. Assuming a Unit Back Wash Volume of 150 gal/sf, a backwash volume of 158,000 gallons is calculated for washing one filter. To replenish the water supply tank with 158,000 gallons, it takes one of the 972 gpm pumps about 2.7 hours. Therefore, the most that each of the eight filters can be washed is once daily, considering the capacity of the washwater supply system. There are currently no strict requirements to leave a filter for a set time before returning it to service. However, operations staff tries to maximize the "rest time" of every filter before returning it to service by utilizing good rotation of the filters. Most of the year, the filters are allowed to rest for 12 hrs or longer after a wash before returning them to service. However, during high production days, and specifically high color in the raw water, it is not uncommon to need to return a filter to service immediately after washing. 5.1.1.6 Disinfection Disinfection at the BWTF is accomplished by application of sodium hypochlorite solution. The conversion to liquid sodium hypochlorite from gaseous chlorine was completed in early 2000. The new liquid chemical storage and feed facilities were designed to feed up to 5 mg/L at a plant flow rate of 50 MGD providing capacity consistent with the BWTF design capacity. The sodium hypochlorite is fed upstream of the filters. Since the installation in 2000 by treatment plant staff, the following changes to the system have taken place: • The pre-basin NaOCI feed points were moved downstream of the coagulant feed • Operations staff have all but stopped using pre basin chlorination due in an effort to minimize DBP formation potential • A "post-basin" feed system was installed by water treatment staff in 2004. This system includes feed lines that are located on the basin lines that run from each basin and connect to the main header piping before the filters. • The feed system includes a total of four Watson Marlow peristaltic feed pumps. Each pump is dedicated to a single basin effluent line. The pumps for this system are located in the hypochlorite room within the containment wall. • Operations staff manually controls the flow of each pump as there are no flow-meters currently installed on this system. • This post basin system was originally fitted with orifice meters to measure the flow of each pump. These meters had to be eliminated due to constant plugging. • A double "Y" strainer system was installed (and remains) on the suction line to the post basin pumps to filter out particulate matter that could potentially clog the pumps or flow meters- • Minor piping modifications and general maintenance (such as tank inspection/repair) has taken place since install. • The floor is scheduled to be re-sloped and repainted with epoxy in Sept. 2010. This work is needed due to major deterioration of the epoxy coating and concrete floor. The containment wall and floor joint will also be sealed to fix the leaking wall. The floor of the hypochlorite containment area was originally designed for 1 ton CI2 gaseous tanks and was not properly retrofitted when it was converted for use as hypochlorite storage/containment room. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-19 As discussed later in this section, CDPHE requires a minimum contact time prior to the first customer tap of 30 minutes at peak design flow to meet disinfection requirements. At a flow rate of 50 MGD a volume of 1.04 MG of effective storage volume would be required to provide the minimum chlorine contact time. The required volume can be provided by any combination of pipes and storage tanks following the filtration step. Storage tank volume is derated to account for the potential for short-circuiting by applying a factor to the total volume. Factors used by CDPHE range from 0.1 for unbaffled tanks to 0.7 for well baffled tanks. Pipeline volume is assessed using a factor of 1.0. The Betasso plant's two treated water storage reservoirs have a total volume of 4.2 MG. Tank No. 1 has a volume of 2.5 MG and is well baffled. As a result a factor of 0.7 is applied to the total volume to obtain an effective volume of 1.75 MG. Tank No. 2 is unbaffled resulting in the 1.7 MG total volume being reduced to 0.17 MG effective volume by applying a factor of 0.1. Without considering the available volume in pipes, the combined total effective volume of 1.92 MG provided by the storage reservoirs would provide the required 30 minute contact time for a peak flow of 92 MGD. This provides approximately 1.8 times the minimum volume required to meet minimum CDPHE requirements for a flow of 50 MGD, which offers a substantial range of operating flexibility. 5.1.1.7 Flow Measurement Raw Water Flow Metering: Low measurement is an ongoing concern at the BWTF_ Influent flow is currently measured upstream of the plant in two main locations: in a new pitot tube flow meter on the new Betasso pipeline, downstream of the Betasso Hydroelectric Facility, and in two ultrasonic flow meters on the Lakewood pipeline, downstream of the Lakewood Hydroelectric Facility. These flow meters should be accurate, but there is no way to independently confirm their accuracy because there is no way to accurately measure combined influent flow at the head of the BWTF. There is an existing combined influent 5 foot Parshall flume at the head of the plant, but it is not used for flow measurement due to inaccuracies caused by turbulence. Treated Water Flow Metering: The plant also has effluent Venturi Tube flow meters on both the Sunshine Canyon and the 6t" and Canyon effluent pipelines. These flow meters are essential for determining efficiencies in delivery and recording of treated water downstream of the treatment plant, as well as for determining losses through the treatment process. The effluent flow meters are theoretically highly accurate, but there is no way to independently confirm their accuracy, and there are several potential issues that can degrade the accuracy of Venturi Tube flow meters. Discussions with plant staff confirm that these flow meters are unreliable and it also was a concern raised in The City of Boulder Water Conservation Futures Study, performed in 1999 by Hydrosphere Resource Consultants, Inc., which states that 8.4% of the City of Boulder's treated water is unaccounted for, some of which may be due to poor flow measurement. 5.1.1.8 Chemical Systems Each of the chemical systems used at the BWTF was analyzed for its capacity to supply the required dosages of treatment chemicals over the design range of flow rates- The results are summarized below- Aluminum sulfate (alum) is used as a primary coagulant. Alum is stored in liquid form and fed directly to the influent raw water at the inlet to the Parshall flume. Two metering pumps are in place, each with a capacity of 66 gallons-per-hour (gph). Assuming an active solution concentration of 50 percent, this system has a firm capacity to treat up to 79 MGD at an average dose of 12 mg/L. Alternatively; this system could deliver up to 20 mg/L of alum at a plant flow of 50 MGD with one metering pump out of service- With both pumps in service, the system could deliver up to 40 mg/L of alum at a plant flow of 50 MGD. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-20 The possible locations for feed points are limited due to the physical limitations of the facility. There are no current plans to move the feed points at this time. Other feed locations have been tried in the past with mixed results. Polymerized aluminum chloride (polyaluminum chloride, PACT) can be added to the influent raw water along with the alum, as a coagulant aid. PACI is stored and fed as a liquid with a solution strength of 50 percent active PACI. Currently, this system has one metering pump that has a maximum capacity of 70 gph, which could feed up to 22 mg/L of PACI at a plant flow of 50 MGD. The average application dosage used at BWTF is 5 to 7 mg/L. Polymer as a floc-aid has never been trialed or used on a long term basis. Occasionally, operators have hand-dosed summaclear or alum to the filter influent during high color/turbidity events with good results. They take a small beaker containing coagulant and pour it into the influent channel of the filter (or sometimes on top of the filter media) when the filter is first brought on-line which reduces ripening time and minimizes turbidity spikes. A system for feeding powdered activated carbon (PAC) to the influent raw water is in place, but has never been used. This system was designed to store PAC slurry at a concentration of 1 lb of PAC per gallon of slurry and to feed up to 1.0 mg/L at a plant flow rate of 50 MGD. Lime is added after filtration in the filtered water flume as part of the corrosion control treatment. Lime is stored in powder form and is fed as a slurry. The dry chemical is metered by two volumetric screw type feeders having a capacity of 3,800 lb/day each. The target concentration of lime slurry that is added to the finished water flume is 30%. The existing system could supply that dose to a flow of 32 MGD. At a plant flow rate of 50 MGD, the system could supply a dosage of 18 mg/L. The lime feeders are maintenance intensive and the scale buildup is a source of frustration for the operations staff. The City of Fort Collins, Colorado has a newer lime slaking system that can maintain a constant temperature close to the required 185 degrees F where the lime surface area is maximized. The greater the lime surface area, the more consistent and reactive the lime will be, which will result in a more accurate dose. In addition, the higher the quality of hydrated lime, the less scaling will occur. Fluoride is added using liquid hydrofluosilicic acid. A single metering pump with a capacity of 300 gpd provides the capacity to add up to 12 mg/L of fluoride at plant flow rate of 50 MGD with a solution strength of 20 percent. Again, assuming a solution strength of 20 percent, this system could maintain a 1.0 mg/L fluoride concentration at a flow rate of up to 60 MGD. Carbon dioxide (C02) is added to the finished water after lime addition to adjust the Langlier index for corrosion control. C02 is fed as a gas through a diffuser grid mounted in treated water reservoir No. 1. The existing system has the capability to feed up to 5,000 lb/day which is sufficient to apply up to 12 mg/L at a plant flow of 50 MGD. This analysis indicates that, except for the lime feed system; the existing chemical systems have enough capacity to supply the required quantities of treatment chemicals at a peak day plant flow of 50 MGD. Assuming an average 28 mg/L lime dose continues to be required, it would be necessary to increase the lime feed capacity to 11,700 lb/day from the existing 7,600 lb/day. Chemical feed rates are currently adjusted manually based on plant flow and water quality demands. Systems are monitored remotely through the SCADA system, but the plant operators determine the appropriate dose for each chemical at intervals through the operating day and manually adjust the feed equipment set points. Although the SCADA system does provide for remote monitoring of the chemical systems, this is a manual system because the operators have to determine the set points and adjust the City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-21 feed equipment by hand. The plant operating staff indicated that more efficient chemical use and higher levels of water quality could be achieved more consistently if the SCADA system was used to automatically make more frequent and more precise adjustments to the chemical feed systems than is possible with the existing manual adjustment procedure. The existing storage facilities for liquid chemicals have developed by adapting existing storage and feed equipment as beneficial changes in treatment chemicals were made. For example, polyaluminum chloride is currently stored in tanks that were originally used to store alum. These arrangements have been workable as temporary facilities. However, long term, operability and reliability would be enhanced by upgrading these facilities. In addition, the plant operating staff has determined that in order to optimize process performance a flocculant aid polymer system and possibly a filter aid polymer system may be needed. All of these improvements were originally part of the Residuals Project but were eliminated to reduce project costs when project bids exceeded available funds. 5.1.1.9 Process Instrumentation and Control Effective process performance is dependent on accurate measurement of the water quality parameters that reflect current operating conditions. This information is used to determine the need for and magnitude of adjustments to chemical feed rates and other process controls to maintain optimal performance. As previously discussed, the plant SCADA system provides for remote monitoring, but process control is manual. The SCADA system also records plant operating data in great detail. Plant influent flow is measured separately on the Barker and Lakewood pipelines using pitot tube flow meters. A combined influent flow meter is desired to measure total inflow to the BWTF. The flow split among the operating flocculation/sedimentation basins is monitored by individual flow tubes at each basin. It is believed that the flow split to each basin is not even and improvements to the flow splitting structure are recommended. Accurate control of the flow to each basin will facilitate optimization of the processes. Flow to individual filters is measured by flow tubes. Flow to each filter is currently controlled by pneumatically actuated butterfly valves, which are worn and should be replaced as part of the next capital improvements project. A turbidity meter installed at the Lakewood pipeline intake provides information on raw water turbidity changes to allow the plant operators to respond to turbidity spikes. Otherwise, there is no water quality instrumentation on the raw influent water lines ahead of coagulation. Settled water turbidity is measured individually on the effluent from each basin and collectively in the distribution header to the filters. No accuracy concerns were reported by staff, but the data for the individual sedimentation basins is difficult to access from the SCADA system and is not regularly used in process operation. Individual turbidity meters and particle counters are installed on each filter effluent. These are reported to give acceptable results. One improvement to allow better assessment of filter performance could be to replace the turbidity meters with laser turbidity meters to provide better resolution at very low turbidities, however the City does not need the additional resolution at this point in time. A streaming current monitor is installed in the piping between the Parshall flume and the flocculation/sedimentation basins to provide data on performance of the coagulation process and is reported by staff to work well. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-22 The zeta potential meter in the plant lab is used to measure coagulation performance. Components of this meter were updated in 2006 and it is reportedly working well. The Venturi tube flow meters used to measure plant effluent discharged to the Sunshine Canyon and 6th and Canyon transmission mains leaving the plant were identified by the Water Conservation Futures Study as possibly being inaccurate and in need of recalibration or replacement to facilitate accurate water use data. An on-line pH meter is used to determine lime and CO2 feed rates for chemical stabilization. It was not reported to be presenting difficulties to operations staff. Online alkalinity meters are no longer used because they were found to not perform well and did not provide useful data, there are currently no plans to replace the alkalinity meters. In addition to the need for automation of chemical systems previously noted, plant staff indicated that better access to the data currently being measured by existing instruments and recorded by the SCADA system is essential to optimizing plant performance. The existing SCADA system is reported to have the capability to present data more readily in easy to use formats but additional software and programming is needed. Operators also indicated that a general upgrading of the on-line instrumentation would reduce the amount of laboratory work needed and provide operators with critical data faster, thereby facilitating more responsive operation. 5.1.1.10 Residuals Management Despite the projects implemented in 1999 and 2006, the residuals handling capacity at BWTF is still inadequate and this is considered one of the top priority issues by plant operations and project management staff. For the preliminary evaluation of the solids handling process presented in this report, MWH interviewed plant Operations and Maintenance (O&M) staff and reviewed the 2005 Carollo report and subsequent project design drawings. MWH has estimated the solids production for the BWTF based on influent water turbidity, plant flow, and typical and maximum reported coagulant dosing. Based on aluminum contribution of PACI and Alum coagulants, 0.58 pounds of PACI produces the equivalent amount of solids (predominantly aluminum hydroxide) as one pound of Alum. The solids production estimates are calculated from the following equation: S = 8.34 x [(Alum x C) + (PACT x C x 0.58) + (NTU x F)] Where: S = Solids production in dry lb/MG water treated 8.34 = conversion factor [(Ib/MG)/(mg/L)] Alum = Alum dose in mg/L PACI = PACI dose in mg/L C = conversion factor (lb alum/lb dry solids) NTU = Influent Turbidity F = Turbidity to suspended solids conversion factor [(mg/L TSS)/NTU] The average daily solids production (dry lb/day) for each scenario is the solids production multiplied by the flow (Q) in MGD. A summary of the estimated solids production is shown in Table 5-22. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-23 Table 5-22: Estimated Solids. Prod!iction at BWTF Quantity Average Peak Description Unit Day Peak Day Week At 46 MGD Origin Plant Flow Rate (Q) MGD 14 40 25 46 Given Raw Water Turbidity (NTU) NTU 4 4 4 4 Given NTU to TSS Conversion (CONY) mg/L/NTU 1.23 1.23 1.23 1.23 Carollo 2005 Alum Dose mg/L 11.1 16.2 16.2 16.2 Given Sumaclear (PACT) Dose mg/L 6.9 14 14 14 Given Solids Produced dry Ibs/MG 74 94 94 94 Calculated Daily Solids Production dry Ibs/day 1,033 3,751 2,344 4,313 Calculated Drying residuals via lagoons is a relatively long term method in comparison to the available dewatering options. There needs to be sufficient capacity in order for this method to be effective since lagoon operation repeats and the overall cycle time for each lagoon varies depending on filling, drying, and excavation times. At the average day rate of 1,033 dry Ibs/day of estimated solids produced, approximately 377,045 Ibs is produced per year. This is used to estimate the total size of the sludge drying beds required to handle the solids production flows at the BWTF, which is shown in Table 5-23. This evaluation is provided to illustrate the capacity needed to manage the solids production and the possible options available to meet these needs. Further studies and field tests need to be conducted to determine the appropriate design criteria for sizing of lagoons. Loading rates may vary between 6 to 12 Ibs/ft2/yr. In addition, because of variations in weather and solids production, it is common to provide excess drying time. Table 23: L_ .I-nated Surface Area RecaOred. IR2cPrJ, on Average Dm! ~~alids Production of 1,033 Dry Ibslcl<:.; Total Lagoon Surface Area Required (ft2) Solids Loading Rates Drying Period 6 8 12 (months) (Ibs/ft2lyr) (Ibs/ft2lyr) (Ibs/ft2lyr) 12 31,420 47,131 62,841 15 39,276 58,913 78,551 18 47,131 70,696 94,261 Assuming it takes a full 12 months for one drying bed to be sufficiently loaded with solids, decanted, dried and then excavated, some contingency is applied if the drying period were to be extended to 15 months or even 18 months. In keeping consistent with solids loading rate of 8 Ibs/ft2/year from the 2005 Carollo report, and selecting 15 months as the drying period, a total surface area of approximately 59,000 ft2 is required. Ideally, the plant would be able to cycle through four lagoons each with a surface area of 14,750 ft2, however, according to the 2005 Carollo report; the total surface area at the plant is currently 34,000 ft2. This illustrates the shortfall in lagoon capacity which has been experienced and reported by the plant's staff. If land space were not an issue, then the existing sludge lagoons can be expanded and modified to accommodate the BWTF's solids production, but this is not the case. There have been improvements City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-24 made to the South Lagoon to allow for more effective decanting, but dewatering capacity has been reduced with the lining of the lagoon. The underdrain system for the east half of the North Drying Beds is broken and no longer operational. The beds are essentially operating as decanting lagoons. The remainder of the residual drying is achieved by evaporation. The beds are cleaned periodically and the residuals stored on the residuals drying pad until disposed of offsite. To keep up with inadequate capacity of the existing lagoons, the BWTF currently uses private contractors to dewater the excess solids. This is a temporary arrangement and the staff will require a more robust solution. Due to potential pretreatment capacity limitations of the existing flocculation/sedimentation process described in Section 5.1.1.3, two approaches can be taken for residuals handling solutions at the BWTF. The first approach is to address the issues separately which allows for separate analysis, planning, funding, and implementation schedules. The second approach is couple them together based on a conversion to dissolved air flotation (DAF) for pretreatment which is similar to one of the alternatives presented in the 2005 Facility Plan for pretreatment capacity and performance improvements (Note: The DAF alternative in the 2005 Facility Plan only includes 22 MGD of DAF capacity). This second approach requires simultaneous analysis, planning, funding and implementation schedules for the pretreatment and residuals handling improvements. Depending on the City's needed and desired implementation schedule for each of these improvements, the second approach may introduce undesirable funding and/or scheduling constraints. Brief descriptions of these alternatives are presented below with advantages/disadvantages summarized in Table 5-24 along with budgetary capital costs. Alternative 1 includes the addition of a gravity thickener and a mechanical dewatering process to handle residuals flows from the current sedimentation basins to provide a dewatered (approximately 20% solids) sludge for disposal. For the purposes of this planning level analysis it is assumed that the mechanical dewatering process is accomplished using centrifuges. When further analysis of residuals handling improvements is made, it is recommended that belt filter presses and centrifuges be compared from cost and operations perspectives with City staff to determine the best equipment choice for the BWTF. It is assumed that either process will require polymer addition for effective dewatering. Based on the solids quantities from Table 5-22, two 20-foot diameter gravity thickeners loaded at approximately 6 Ibs/ft2/day are required to accommodate a 46 MGD plant capacity. The dewatering centrifuges are assumed to be located on the second floor of a dewatering and residuals load out building. Figure 5-20 indicates a potential site layout for these facilities. Note that the drawing is schematic only and an alternate location may be necessary to continue use of the Residuals Drying Pad if the project is phased (e.g. only thickening installed) or for constructability or other reasons. Alternative 2 includes the addition of a mechanical dewatering process to an early implementation of pretreatment capacity and performance upgrades with DAF that includes the following: • Demolition of two existing flocculation/sedimentation basins • Fill concrete floor to required elevation • Construct new interior walls for 3-stage flocculation and DAF floatation • Install eight DAF trains and associated equipment, 5.75 MGD each train • Peak SOR = 6.25 gpm/ft2 at 46 MGD City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-25 Since a DAF pretreatment process typically produces a 2-6% float, a separate pretreatment residuals thickening process (i.e., gravity thickening) can be eliminated. As with Alternative 1, dewatering is assumed to be accomplished using centrifuges. The dewatering and residuals load out building is assumed to be located as indicated in Figure 5-20 for Alternative 1. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-26 ^f !7'7F Site Plan Showinq Location of Gravity Thickeners and Centrifuge Building I(EY MOTES RESIDUALS DRYING PAD, v \ f 0.1 E%IS11N{: SOUTH SLUDGE L-.i ON INSTALL NEW RAW AND FINISHED WATER 002 SOLUTION D 25 501W' Y FEED SYSTEMS INSIDE PIPE GALLERY OF THE FILTER / BUILDING. a J OUT NEW 0022 CAS PIPE TO NEW COL SOLUTION FEED ` \I • V MCOIFY uis-n K PALL STORAGE AND PIPING. \ 1 Y y (61 INSINL NEW -.1 FL45H MLC SYSTEM, F, Grevil TNlckeners Eer•:eyar Buildmq -Tluck Laadln Sa - 0 rL ~ Bt 92 SLUC~` O y 83 e. aA SLUDGE FILTNAiE~ tl _ fm- laoor _ aaw WAiE \ ~M1 ~ UkAp - s SPENT BACKWASH REOYUE _ ~YIDtl' e.2, 1 COUAL12A7I0N UbN P~TETRCATMENi SWGN TIHIGIIm WATER AUILDINC V. SEE DRAWING C-2 STORAGE FOR YARD PIPING ESERNOIR _ - ! INFORMATION tlG',2 Y - A K.~ ~r ss r. am - . roawAr CO TM'H OCOIMCNATION SLOWDNTATION 5ED14rNIATION f y~, BASIN NO.H BASIN N0.3 EASIN NO1 I ~.L :i :L I FINISHED WATER STORAGE RESERVOIR { I' LPG TANK N'0. 1 4 SA INISTRA L T BUILDING 6 3 II 5.A6 \ 4b _ EWDO SOIL BORINGS' VAVLT REFER TO GEOTEOHNICAL ENGINEERING AND GEOLOGY STUDY CONDUCTED BY KUMAR & ASSOCMTES, INC. MAY 30, 2006. BENCH MARK NFORMATIOW m7n ~'A SURVEY BY CALVADA SURVEYING, INC. MAY 5, 2006. BMI: .ne TOP OF SOUTHEAST CORNER OF ELECTRICAL CONTROL CONCRETE PAD NEAR NORTH LAGOONS DECANT STRUCTURE. ELEVATION ASSUMED 6306.50 FT PER AS-BUILT DRAWING MARKUP OF -BETASSO WATER TREATMENT PUNT RESIDUALS/RECYCLE PRETREATMENT FACILITIES DID NO. 51-99,- DATED 1999. SEE m~ DWO LS-1 AND LS-2 FOR FURTHER INFORMATIONS - City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-27 7-24: Residuals Y-7nf!IPnri lmnr^,,oernents Alternatives Capital Alt. Description Advantages Disadvantages Cost • Lower initial and overall capital Existing Floc./Sed. cost • May result in "throw away" 1 Process with Gravity Prevents "early" expenditure of thickening process if DAF $2 858,000* Thickener and , process is chosen for future Centrifuge Dewatering funds for pretreatment pretreatment upgrades improvements • Requires pretreatment improvements be implemented Smaller overall footprint "early" along with dewatering • Conversion to DAF and Increases pretreatment power 2 . Pretreatment consistency with $25,000,000 Centrifuge Dewatering BRWTF consumption • Higher overall residuals handling and pretreatment improvements costs' *Alternative 1 does not include upgrades to the pretreatment improvements whereas Alternative 2 inherently does. To make this an equal comparison, an estimate 2010 capital cost of $13.1 M would need to be added to Alternative 1 to add plate settling and associated flocculation pretreatment improvements in all four existing flocculation/sedimentation basins per the 2005 Facility Plan, resulting in a total of $15,958,000. Based on the advantages and disadvantages and costs of the two alternatives, it is recommended that Alternative No. 1 be evaluated further with respect to optimized sizing for the range of flows and loads and desired redundancy, site layout, and preferred mechanical dewatering equipment (centrifuges or belt filter presses). 5.1.1.11 Plant Hydraulics The process flow conveyance network of pipes and channels was analyzed previously for hydraulic capacity. At a peak flow of 50 MGD no hydraulic limitations were identified. This hydraulic study was performed for the 2000 update to the TWMP. If any changes to the piping or process flow has or will change, another evaluation of the hydraulics through BWTF should be performed. 5.1.1.12 Betasso Water Treatment Facility Capacity The results of the evaluation of major unit processes and systems of the BWTF are summarized in Table 5-25. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-28 Table 5-25: BWTF Capacity Evaluation Process Criteria Rated Capacity Potential Capacity Comments 27.7 MGD is the normal max for the Barker supply. For very short term emergencies of up to a day or so, the max capacity could be 40 MGD because Kossler can be drawn down since the gravity line would not be keeping up that level of flow. 47.7 MGD Under emergency conditions, However, this might do some lining damage to the Raw Water Pipe Hydraulic Capacity • Barker at 27.7 MGD flows could reach up to 30.1 Betasso Penstock if it continues very long. In a Conveyance from Barker and 30 mgd from longer term emergency, the additional water would • Lakewood at 20 MGD Lakewood, totaling 60.1 MGD have to travel through the gravity line at the same rate as is being used to avoid draining Kossler, 30.1 MGD is assumed for a longer term emergency, however, 35 MGD would need to be put in the upper end of the gravity line to get 30 MGD out. Assumed rapid mix equipment was going to help, Coagulation 50 MGD 50 MGD however after installation, no improvements were seen. This capacity is likely less due to the rapid mix system. Flocculation Hydraulic Detention Time <42 MGD at HDT > 30 minutes 50 MGD at HDT = 25 minutes Baffle configuration does not provide optimum flocculation conditions Assumes installation of baffles to improve basin Sedimentation Surface Loading Rate 52 MGD at SLR = 0.6 gpmlft2 60.5 MGD at SLR = 0.7 gpmlft2 length-to-width ratio. Allows for one filter off line for backwashing. Note that BWTF has never run at these rates and has typically been run at rates 33% lower. It is Filtration Hydraulic Loading Rate = 5 53.2 MGD 53.2 MGD expected that these rates would cause operational issues such as high turbidities and short UFRVs. The actual maximum loading rate needs to be verified. Sodium Hypochlorite System 50 MGD 50 MGD Disinfection at 5 mglL To meet CDPHE requirements Chlorine Contact Time = 30 92 MGD 92 MGD minute minimum City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-29 This evaluation indicates that the BWTF currently has the capability to treat a peak flow of approximately 40 MGD to the level required to meet current regulatory requirements. Capacity is limited by the flocculation process but performance data suggests that actual sedimentation capacity is less than the theoretical value due to poor flocculation, possibly poor coagulation and the less than optimum sedimentation basin configuration. All other processes have capacities equal to or greater than 50 MGD and process piping has the hydraulic capacity to convey 50 MGD without restriction. Replacement of the Lakewood Pipeline has reduced previous entrained air problems in the raw water, which has improved the performance of the flocculation and sedimentation processes. However, elimination of the entrained air alone has not increased the capacity of these processes to 50 MGD. Additional improvements will be needed to the flocculation and sedimentation basins to provide a fully effective treatment barrier with the consistent performance necessary to reliably meet current and future regulatory requirements at a capacity of 50 MGD. 5.1.1.13 Miscellaneous The standby generator capacity at BWTF is at its maximum capacity. If additional loads are added, the capacity of standby generation will need to be increased. 5.1.1.14 Chemical and Energy Efficiency Patterns Chemical usage varies due to seasonal and source water quality changes. Discussions with staff indicate that the City makes significant efforts toward chemical optimization. Continued monitoring, optimization, and experimentation efforts will likely lead to further improvements with regard to chemical efficiency. Chemical efficiency can also be improved through the automation of various chemical feed systems found throughout the plant, with the addition of PLC controlled flow pacing and trim capability. Utilizing feedback from process controls instruments, continuous adjustments can be made automatically through the PLC logic in order to consistently provide the proper chemical doses at all times. Energy efficiency at the BWTF can be improved over time with the use of higher efficiency pumps and premium efficiency motors as part of the maintenance replacement program and as part of facility upgrade designs. 5.1.1.15 O&M Procedures and Maintenance Programs Based upon site visits and discussions with O&M staff, there is some room for improvement with regard to the completion of routine maintenance operations. Budgetary and manpower limitations generally limit maintenance activities to those items with mid to high priority, leaving items with low to mid priority unattended to. It should be expected that as the equipment and facilities age, maintenance needs will increase, and there could be a need for additional budget and manpower to properly maintain the facility and avoid premature replacement of equipment. The City is in the process of transitioning toward the use of computerized maintenance management software. This system will allow the City to more easily schedule and plan for routine maintenance activities. It is reported that a large commitment of time is required to enter all the necessary data for the system to become fully functional, it is likely to be several years before the system is fully functional. 5.1.1.16 Needs for Continued Water Quality Compliance At this time there appear to be no water quality compliance issues when treating within the inherent capacity limitations identified in previous sections. 5.1.1.17 Future Water Quality Issues If the regulatory limits for DBPs are lowered significantly in the future, the City may not be able to comply. Should the running annual average limits be lowered to 0.040 mg/L for TTHMs and 0.030 mg/L for HAAS City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-30 as has been speculated, disinfection byproduct concentrations would need to be reduced well below current levels to achieve compliance. Since relatively high levels of source water control for the BWTF have already been implemented and NOM material seems to be related to spring run-off conditions, additional changes to disinfection practices or preoxidation treatment with chlorine dioxide may become necessary to meet future DBP limits. 5.1.1.18 Waste Impoundments MWH performed a preliminary identification and evaluation of the existing waste impoundments at the BWTF. The evaluation of the impoundments at these facilities is based on discussions with laboratory and plant operations staff and summarized in the following sections. Waste impoundments at the BWTF include a residuals filtrate recovery tank, spent backwash equalization tank, filter to waste recovery tank, a concrete pad, and residuals drying lagoons- Decant from the residuals drying lagoons is sent to the residuals filtrate recovery tank and then on to the spent backwash equalization (SBE) tank that discharges to a DAF thickener. Waste filter backwash water is conveyed to the spent backwash equalization tank and then on to the DAF. Settled solids from the sedimentation basins and float from the DAF are sent to the residuals drying lagoons. Filter to waste flows are conveyed to the filter to waste recovery tank and then returned to the main flow stream just upstream of the rapid mixer. The concrete pad is used for drying and storing the dried residuals. A schematic of the residual flow streams are shown in Figure 5-21. Betasse WTF Facility 001 FiRerto - =optbrai AF - - • - • - > Lagoons It'PbL'Y~+ I > tank - - Filter 8 Filter 7 I Basin 4 Spent _ I 3ackv,ash Recovery Filter 6 Floc ISed Basin 3 3 I Filter 5 6 Filter 4 Z I Dissalved 44 i Floe / Sed " Floatation Filter 3 I Basin 2 I (pretreatment) Filter 2 - Floc;Sed Filter 1 Basin 1 Filtrate, Tank Plard Influent There are two types of construction for the existing residuals drying lagoons. The south lagoons are built of reinforced concrete walls and floors and the north lagoon are constructed of asphaltic concrete floors and reinforced concrete walls. The filtrate tank is a fabricated steel tank. Both the backwash City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-31 concentrating and the backwash equalization tanks are constructed of reinforced concrete walls and floors. An aerial photograph of the existing plant site showing the waste impoundments is presented in Figure 5-22. Figure 1= 14, 5 r~ ~ 'L fri; rs r r . ~ - ~ 1111 1 ~ i '4,. T .M1~y~ F, } k i~_•I. -IL ~"~q ~ tt !a• bra -"Cy. t s` a.r X •y " ~ 4 4 Z t' 7s` - 6-C rim M1r Y, 5- 4- . ~r t CL do AOL, q' -bJ City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-32 5.1.1.19 Residuals Sampling The City of Boulder received the results of the residuals sampling that was performed in August of 2010 on the BWTF residuals. The results of these samples are included in Table 5-26 and 5-27. Table 5-26: Analytical Results from BWTP Residua. Anal a Result' Units Aluminum 68,000 m /K Arsenic 6.2 mg/Kg Cadmium ND mg/Kg Chromium 13 mg/Kg Copper 31 mg/Kg Iron 20,000 m /K Lead 30 mg/Kg Molybdenum ND mg/Kg Nickel ND mg/Kg Potassium 1,300 mg/Kg Selenium ND mg/Kg Zinc 69 mg/Kg Mercury 57 /K Ammonia 310 mg/Kg Nitrogen, Keldahl 5,600 mg/Kg Nitrate as N-Soluble ND mg/Kg Total Phosphorus ND mg/Kg Orthophosphate as P-Soluble ND mg/Kg Total Organic Carbon 96 /K Percent Moisture 63 % Total Solids 42 % Soluble pH adj. to 25 de C-Soluble 6.74 SU Specific Conductance - Soluble 170 umhos/cm 'Results from: Analytical Report by TestAmerica 7/20/2010 Water Treatment Residuals Analyses, job number 2804779-1. Table 5-27: Radiochem" VTP Residua' Result - Result - Regulatory Limits for Disposal Anal to Sample 11 Sample 21 Units to meet Exempt StatuS2,3 226Ra 0.810 0.810 ci! 228Ra 1.07 Ci! 2261228Ra 1.88 ci! <3 234U 1.68 1.57 ci! 235U 0.0764 0.0722 Cil 238U 1.34 1.77 cil NATU 3.0964 3.4122 Ci! <30 228Th 1.00 1.11 Ci! 230Th 0.364 0.734 cil 232Th 0.610 0.909 ci! NATTh 1.974 2.753 pci/g <3 Alpha 5.87 4.96 Ci/ <40 'Results from: Analytical Report by TestAmerica 8/11/2010 Water Treatment Residuals Analyses, job number 280-4779-2. 2February 2007 Interim Policy and Guidance Pending Rulemaking for Control and Disposition of Technologically-Enhanced Naturally Occurring Radioactive Materials in Colorado. Rev 2.1, Final Draft for Comment, CDPHE. 3Per 5 CCR 1003-7 and sludge which exceeds 40 Ci/ m total alpha activity cannot be land applied. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-33 Results from the sampling indicate that the residuals are exempt from any TENORM related regulations for disposal. The City has determined that they do not plan on closing any of the waste impoundments at the BWTF or the BRWTF, regardless of the new requirements for waste impoundments. Testing of the residuals for constituents of concern has been ongoing and will continue to be tested. According to the plant's designer, the BRWTF was designed in 1969 to treat 8 MGD to then-current water quality standards. The plant design provided for treatment of up to 12 MGD for short durations under conditions referred to as "overload." Two new filters were added in 1997. In 2005 the flocculation/sedimentation clarifier was replaced with two trains of flocculation basins and DAF units, two new high service pumps were added; and the four residuals lagoons were built. In 2010, a third flocculation/DAF train was constructed, another pump was added to the Raw Water Pump Station, a carbonic acid feed system was installed, and a liquid sodium hypochlorite system was installed to replace the mixed oxidant generation system. The plant is currently referred to as having 20 MGD firm peak capacity. The following evaluation discusses needed improvements of generally high to mid priority. A complete list of improvements including those of lower priority can be found in Section 7 of this report. 5.1.2.1 Raw Water Delivery Raw water reaches the BRWTF either by gravity diversion from the BFC or by pumping from Boulder Reservoir. The raw water intake at the BFC has historically presented an operational problem caused by accumulation of floating material and other contaminants originating from nearby farming activities during certain times of the year. A slide gate was installed to effectively block floating material from reaching the intake. The intake must be inspected and cleaned frequently to prevent plugging. Cleaning is done manually, which is a difficult operation with safety risks. Improvements to the access way and platform are required to mitigate safety risks, as the current structure is reported to be badly corroded and poorly constructed. Additionally, there is currently no power at the intake structure to support the installation of an automatic trash rack and lighting to further improve the safety and security related to this location. The raw water intake in Boulder Reservoir was recently fitted with a fixed level intake structure. This structure allows water to be drawn from a mid level in the reservoir to avoid manganese and algae, thereby allowing the facility to treat the best quality water from the reservoir at a lower treatment cost- The pumps used to draw water from Boulder Reservoir have the capability to deliver up to 28 MGD in increments of 4 MGD with all pumps operational. This pump station includes three 8 MGD pumps and one 4 MGD pump. With one of the larger pumping units out of service, the system provides a firm pumping capacity of 20 MGD. Three of these pumps were installed in the early 1980's, and the fourth was installed in 2010 along with a new PLC located in the pump station and new fiber optic lines between the main plant site and the remote Raw Water Pump Station. Although it has proven to be difficult to justify from power consumption and capital cost standpoints, operations staff could benefit from the installation of a variable frequency drive on at least one of the pumps- The flow from this pump station is currently modulated using a 48-inch butterfly valve located in the yard near the DAF building which has been reported to be well worn and difficult to position. 5.1.2.2 Raw Water Quality Raw water treated at the BRWTF is diverted from the headwaters of the Colorado River and conveyed to the plant via the Windy Gap and C-BT transmountain diversion facilities. At the source, the water is of very high quality but is subject to degradation during conveyance. The C-BT facilities consist of a series of pipelines, tunnels, open canals and reservoirs. While mostly remote or protected from contamination by City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-34 human activities, the open reservoirs and canals offer opportunities for pathogens and chemical contaminants to enter. In particular, the Boulder feeder canal that carries water on the last segment of the system from Carter Lake to Boulder Reservoir is an open channel that is vulnerable to contamination particularly from agricultural activities. This is also true for the natural drainage channels that are tributary to Boulder Reservoir. Boulder Reservoir receives drainage from the plains and foothills to the west, which has a different water quality from the C-BT water delivered by the canal. In addition, various minerals tend to accumulate over time in a reservoir. Of particular concern is the accumulation of manganese in the reservoir sediments. When anaerobic conditions develop at the bottom of the reservoir, manganese will be released into the water. This dissolved manganese must be oxidized early in the treatment process to ensure removal so that staining of customers' clothing and plumbing fixtures does not occur. Although the BFC is the preferred source for the BRWTF, it does present its own challenges. The canal is vulnerable to contamination by runoff entering via forty three stormwater outfalls that drain directly into the canal. Land uses in the areas tributary to these outfalls include agricultural (crops and cattle grazing), industrial, and residential; presenting the potential for various types of contamination that could go undetected. City Water Quality staff also report that the water carried in the canal is the City's most protozoan contaminated raw water source. The canal is also prone to severe turbidity spikes associated with summer storms. Reportedly, turbidity may reach 700-800 NTU within minutes due to storms that may be located many miles from the plant site. Currently the solution is to shut down the plant until the turbidity spike passes. Another issue associated with use of water from the canal is difficult-to-treat tastes and odors attributed to algae. The installation of online monitoring of basic raw water quality parameters such as turbidity, TOC, and ORP upstream of the intake structure would aid the City in anticipating severe water quality events. When water is not flowing in the canal (typically Nov. 1 to Apr. 1) Boulder Reservoir water must be used. One of the most significant factors affecting the operation of the BRWTF is the difference in water quality between water drawn directly from the BFC and water drawn from the Reservoir. Figure 5-23 shows that water drawn from the reservoir is generally higher in turbidity than water taken from the canal. However, the canal is vulnerable to sharp, large turbidity spikes that can quickly overwhelm the treatment process. As shown on Figures 5-24 and 5-25, pH and alkalinity also differ between the reservoir and the canal. Water from the reservoir has an average pH of just over 8 while the pH of water from the canal averages over 8.2. Alkalinity varies sharply between the two sources. Water from the reservoir has alkalinity typically in the range of 50 to 90 mg/L but water from the canal ranges from 25 to 45 mg/L. Since the plant does not have the capability to adjust alkalinity the alkalinity of the finished water tends to vary over the same ranges as the raw water, resulting in operational problems and complaints from commercial users who have manufacturing processes that are sensitive to water chemistry. 5.1.2.3 Coagulation As at the BWTF, coagulation at BRWTF is enhanced by chemical addition. Systems are in place for the addition of polyaluminum chloride or aluminum sulfate as the primary coagulant, and cationic polymer as a coagulant aid. Chemical feed systems are evaluated later in this section. In 2005, a flash mixer and a static mixer were added to the 42-inch raw water line in the pretreatment building, providing the City with reliable means for mixing chemicals with the raw water. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-35 Figure 5-23: BRWTF Raw Water Turbidity 35 - 30 25 • O z 20 . • • •i 47 r . a 15 • ~ ~ • Y ~ - ~ ~ 10 ,~I' 1 •Mt t w •=t 1 0 Feb-05 Aug-05 Feb-06 Aug-06 Feb-07 Aug-07 Feb-08 111.08 Jan-09 Jul-09 • Reservoir Raw Turbidity • Canal Raw Turbidity Figure 5-24: BRWTF Raw Water pH Probability - 2005-2009 9 8.8 - - 8.6 - 8.4 Canal Average pH = 8-23 8.2 8 - - 7.8 7.6 Reservoir Average pH = 8.06 74 7.2 7 0 011 0.2 03 0,4 15 016 0,7 0,8 09 1 -Reservoir pH - Probability -Reservoir Average pH -Canal pH - Probability -Canal Average pH City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-36 Figure 5-25: BRWTF Raw Water Alkalinity Probability - 2005-2009 90 80 Reservoir Average Alkalinity = 66.7rng/L 70 - 60 50 40 30 20 Canal Average Alkalinity = 32.6rii 10 0 - 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 -RcscrvoirAlkilinity•Probability. -RcscrvoirAvcrapicAlkilinity ~CanalAlkalinity •Probability -CanalAvcrigcAlkalinity 5.1.2.4 Flocculation/Clarification Basins Preliminary treatment at the BRWTF consists of three trains of three-stage Flocculation and DAF. The capacity of this type of process is typically evaluated on the basis of surface overflow rate- Each of the three DAF basins at the BRWTF are 39 feet long and 29 feet wide providing a surface area of 1,131 ft2 each. At the average design flow of 8 MGD per basin, the surface overflow rate is 4.9 gpm/ft2_ Each DAF basin is capable of treating up to 10 MGD but to achieve this flow, the effluent weirs need to be adjusted to prevent the float beach from becoming submerged. The weirs are currently adjusted to allow for treatment of lower flows of just under 4 MGD and up to 8 MGD. The DAF system is supported by 4 recycle pumps (one for each basin, plus one standby) and two saturator tanks. Each saturator tank has a capacity of 20 MGD and the system can be operated with either saturator running singly or both saturators in parallel. Data collected since the DAF system was installed in 2005 is presented in Figure 5-26. The DAF effluent water falls below the City's internal operating standard of 1.0 NTU more than 95 percent of the time. -..YVTF DAF Effluent Turl: 4.5 4 3.5 - F 3 DAF 41: 95% below 0.81 NTU z DAF 42: 95% below 0.61 NTU 2.5 a a ~ 2 L5 1 - 0.5 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 ~OAFplTurbidiry ~UAFp2TurlsiAity City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-37 5.1.2.5 Filtration The BRWTF has four mixed media rapid sand filters capped with anthracite. Each filter has an area of 930 ft2. Based on the CDPHE design criteria of 5 gpm/ft2 at peak flow rate, the filter capacity is rated at 20 MGD with one filter off line for backwashing. The filters typically run at flow rates much less than the peak (3.3 gpmft2). The actual filter loading rate should be verified by future studies. Figures 5-27 and 5-28 show finished water turbidity from 2005 to 2009. Based on these operating data, filtered water turbidity of 0.1 NTU (the City's internal operating standard for filtered water turbidity) or less are reported 95 percent of the time, with the exception of filter #4 which performs slightly worse than the others possibly due to the fact that the media in filter #4 is approximately one year older than in the other filters. Slightly more sporadic performance occurred shortly after the time that the DAF basins were placed into service, but the overall filter performance has been gradually improving over the last several years. There is a desire to begin planning filter rehabilitation activities in the near future to ensure continued satisfactory process performance and reliability from this process as well as updating the filter control consoles to more current and automated technology. Hgule bRVV I r; miter Cfi`went fuiwaity 0.25 0.2 0.15 0.1 lip - 7A 0.05 kt'r 1Y i W.4' • p i-O 0 Jan-05 Au9-05 Mir-06 Sep-06 Apr-07 Oct-07 May-08 Nov-08 Jun-03 Ran-10 • Filter ulTurbidity Avg • Filter4QTurbidity Avg - Filter ajTurbidity Avg • FIIFei :$4Turbidity Avg City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-38 Figure 5-28: BRWTF Filter Effluent Turbidity Probability - 2005-2009 0.2 i 0.18 • i 0.16 Filler I41: 95% below 0.086 NTU 0.14 Filtertt2: 95°%below 0.079NTU Filtertf3: 95% below 0.095 NTU _ ~ 0.12 FiIl Z er444: 95%below 0.11 NTU 0.1 =o a ~ 0.08 0.04 0.02 i 0 ' 0 0-1 0.2 0.3 0.4 0-5 0.6 03 O's 0.9 1 • alter xlTwbiAfty • fiit?r:LTurbi~dity ril~erb3Turhidity • filter xdTwbi<Bty 5.1.2.6 Disinfection Until 2004, disinfection was accomplished using chlorine gas, at which time an on-site mixed oxidant generation system (MIOX) was installed. In 2010 a liquid sodium hypochlorite system with bulk storage was installed to replace the MIOX system. The new liquid sodium hypochlorite system has the capability to deliver a dose of up to 5 mg/L at a plant flow rate of 20 MGD at each of three separate feed points. The three feed points are as follows: 1. Pre-DAF 2. Post-DAF 3. Post-Filters At a flow rate of 20 MGD, a storage volume of 417,000 gallons would be required to provide the minimum 30 minute chlorine contact time required by CDPHE. The existing treated water storage reservoir at the plant site has a storage volume of 2.34 MG. The clearwell basin located under filters 1 and 2 has a volume of about 185,000 gallons making the combined total volume 2.52 MG. Baffles were added to the clearwell in 2005. When the volume reduction factor of 0.7 for baffled tanks is applied to determine the available contact time a volume of 1,764,000 gallons is obtained. This volume would provide approximately 30 minutes of contact time at a flow of 85 MGD. Additional contact time would be achieved during passage through the plant filter effluent and treated water pump suction piping and in the transmission and distribution piping prior to the first customer connection. Thus, facilities are available to provide adequate disinfectant contact time in accordance with CDPHE requirements at a peak flow rate of 20 MGD. A memorandum from MWH to the City of Boulder in January of 2003, titled "Reservoir Contact Time Improvements," discusses is the existing clearwell size and configuration which limit the ultimate BRWTF capacity to 16.9 MGD with a full (18-foot depth) clearwell and worst case raw water quality from Boulder Reservoir. Such limitations are not related to regulatory contact time compliance, but rather with respect to the City's internal goal of an additional 1.5 log Giardia inactivation by the disinfections process. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-39 5.1.2.7 Finished Water Pumping All of the water produced by the BRWTF must be pumped into the distribution system. Six constant speed horizontal split-case centrifugal pumps are installed on the lower level of the filter building. Each pump has a rated capacity of 4 MGD making the firm pumping capacity 20 MGD with one unit out of service. The need to pump all of the water produced results in a significantly higher unit cost per gallon for water treated at the BRWTF compared with the cost for water produced at BWTF. Plant staff estimates that the cost difference may be as much as a factor of two attributed primarily to an unfavorable power cost rate structure. The high service pumps currently installed at BRWTF are the source of one of the more major concerns at the facility. It is also reported that the pumps do not provide the rated flow rate, although it is unclear at this time if this is related to the damage due to cavitation or not. The pumps are reported to be cavitating, and require rehabilitation more often than should be expected. It has also been noted that the high velocity of the water leaving the pumps is severely damaging the check valves such that they often stick in the open position. This pump station may also be benefited by the installation of variable frequency drives (VFDs) to improve on plant and distribution system operations. 5.1.2.8 Chemical Systems Each of the chemical systems used at the BRWTF was analyzed for its capacity to supply treatment chemicals in the required dose. Carbonic acid is used to adjust the raw water pH to optimize the flocculation process when using either alum or polyaluminum chloride. The optimization of the flocculation process aids in the ability to remove TOC. The system is sized to provide a wide range of C02 feed rates between 5 and 200 lb/hr Of C02. As discussed previously, the raw water alkalinity varies greatly between the basin and the canal. This coupled with diurnal variations in pH significantly impact the amount of C02 that is required to adjust the pH to the desired setpoint. The 60 ton storage tank has sufficient storage for 25 days of continuous operation at 200 pounds per hour. If at some point in the future, additional capacity is required of the system, the City has a larger control valve and diffuser element on the shelf which can be installed to increase the CO2 feed rate to 350 lb/hr. Polyaluminum chloride (PACT) is used as a primary coagulant. PACI is stored in liquid form and fed directly to the influent raw water pipe in the DAF Building either at the flash mixer or the static mixer. Two peristaltic pumps are in place, each with a capacity of 108 gph. The required dosage varies according to the source water. 15 mg/L is typically applied to water diverted from the BFC and 25 mg/L is typically required for water drawn from Boulder Reservoir. At an average dose of 15 mg/L this system has a firm capacity to treat up to 40 MGD. Alternatively, this system could deliver up to 15 mg/L at a plant flow of 20 MGD with one metering pump out of service. Aluminum Sulfate (Alum) is used as an alternate primary coagulant. Alum is stored in liquid form and fed directly to the influent raw water pipe in the DAF Building either at the flash mixer or the static mixer. Two peristaltic pumps are in place, each with a capacity of 108 gph. The required dosage varies according to the source water. 25 mg/L is typically applied to water diverted from the BFC and 50 mg/L is typically required for water drawn from Boulder Reservoir. At an average dose of 50 mg/L this system has a firm capacity to treat up to 20 MGD. Alternatively, this system could deliver up to 25 mg/L at a plant flow of 20 MGD with one metering pump out of service. Cationic polymer can be added at either the DAF splitter box as a flocculant aid or to the DAF effluent channel as a filter aid. Polymer is delivered in drums and stored in a 100 gallon tank; the polymer is then metered to a 30 gallon day tank and mixed with water to the desired solution strength. This system has City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-40 one 1 progressive cavity feed pump providing a capacity to feed up to 186 gph of neat polymer solution to a plant flow of 20 MGD. Typical dosage is currently 0.1 to 0.3 mg/L. Sodium hydroxide (caustic soda, NaOH) is used to adjust finished water pH for corrosion control. NaOH is stored and fed as a liquid at a concentration of 25 percent. Two metering pumps each provide a capacity of 42 gph, which is sufficient to deliver an average dose of 15 mg/L to a plant flow of 21 MGD with one pump out of service or 42 MGD with both pumps operational. Fluoride is added using liquid hydrofluosilicic acid. One metering pump with a capacity of 12.75 gph provides the capacity to add up to 15 mg/L of hydrofluosilicic acid at a plant flow rate of 20 MGD. Average required doses range from 0.7 to 0.8 mg/L. This analysis indicates that the existing chemical systems have enough capacity to supply the required quantities of treatment chemicals at a peak day plant flow of 20 MGD. The sodium hypochlorite and carbonic acid feed systems have both been installed in the last year and are up to date with the industry's latest components and control elements. It has been reported by plant staff that all other chemical feed systems at the BRWTF are aging and are currently manually controlled (except the sodium hydroxide system which is automated). Recommended updates to these systems would involve at a minimum the replacement of pumps and installation of instrumentation to allow for more automated control. 5.1.2.9 Waste Impoundments MWH performed a preliminary identification and evaluation of the existing waste impoundments at the BRWTF. The evaluation of the impoundments at these facilities is based on discussions with laboratory and plant operations staff and summarized in the following sections. The waste impoundments at the BRWTF include a washwater recovery basin, primary and secondary lagoons, and a residuals drying pad. Waste filter backwash water is sent to the washwater recovery basin and from there it is pumped back to the influent flow stream to the facility. The primary lagoons receive float from the dissolved air floatation (DAF) process. Decant from the lagoons is returned to the influent flow stream. The DAF float is dewatered and partially dried in the primary lagoons. Further drying and storage of the residuals from the lagoons is provided for in the residuals drying pad. The secondary lagoons serve as redundant backup for the primary lagoons. Figure 5-29 presents a schematic of the residual flow streams for the BRWTF. The washwater recovery basin is a tank of reinforced concrete construction. Reinforced concrete walls and asphaltic concrete floors comprise the construction of the primary lagoons and the residuals drying pad. The secondary lagoons are constructed of earthen embankments and bottoms. Figure 5-30 presents the existing waste impoundments at the BRWTF on an aerial photograph of the facility. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-41 n7'"117F P,esidunl FloAr Streams Boulder Reservoir WTF at Bard St Facility 002 I Dissolved Dissolved Fitter 1 Air Floation Air Floation Fitter 2 2 1 I Finer 3 FloccUatiron FloccUation Filter 4 Some Drains Some Rains ---------f7 00ional I; Washknater c - t . _ . _ . _ R ecawry $ Tank 8 ca Primary Lagoon; Plant Influent MIIIIIIIIIIIIIIIII 1 ti ~ r"Z AIDA + 39 b City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-42 Table 5-28: Analytical Results from BRWTP Residuals Anal a Result' Units Aluminum 23,000 mg/Kg Arsenic 7.5 m /K Cadmium ND mg/Kg Chromium 20 mg/Kg Copper 31 mg/Kg Iron 24,000 mg/Kg Lead 19 mg/Kg Molybdenum ND mg/Kg Nickel 22 mg/Kg Potassium 2,700 mg/Kg Selenium ND mg/Kg Zinc 89 mg/Kg Mercury 39 /K Ammonia ND mg/Kg Nitrogen, Keldahl 970 mg/Kg Nitrate as N-Soluble ND mg/Kg Total Phosphorus ND mg/Kg Orthophosphate as P-Soluble ND mg/Kg Total Organic Carbon 15 1K Percent Moisture 16 % Total Solids 88 % Soluble pH ad j. to 25 de C-Soluble 8.35 SU Specific Conductance - Soluble 170 umhos/cm 'Results from: Analytical Report by TestAmerica 7/20/2010 Water Treatment Residuals Analyses, job number 280-4779-1. Result - Result - Regulatory Limits for Disposal Anal to Sample 11 Sample 21 Units to meet Exempt StatuS2,3 226Ra 1.76 Ci/ 226Ra 228Ra 1.10 Ci/ 228Ra 2261228Ra 2.86 Cil <3 226122BRa 234U 2.03 Cil 234U 235U 0.0452 CI/ 235U 238U 1.38 CI/ 2380 NATU 3.4552 Cil <30 NATU 228Th 0.945 Cil 228Th 230Th 0.402 Ci/ 230Th 232Th 0.686 Cil 232Th NATTh 2.033 Cil <3 NATTh Alpha 8.15 Cil <40 Alpha 'Results from: Analytical Report by TestAmerica 8111/2010 Water Treatment Residuals Analyses, job number 280-4779-2. 2February 2007 Interim Policy and Guidance Pending Rulemaking for Control and Disposition of Technologically-Enhanced Naturally Occurring Radioactive Materials in Colorado. Rev 2.1, Final Draft for Comment, CDPHE. 3Per 5 CCR 1003-7 and sludge which exceeds 40 Cil m total alpha activity cannot be land applied. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-43 Results from the sampling indicate that the residuals are exempt from any TENORM related regulations for disposal. The City has determined that they do not plan on closing any of the waste impoundments at the BWTF or the BRWTF, regardless of the new requirements for waste impoundments. Testing of the residuals for constituents of concern has been ongoing and will continue to be tested 5.1.2.10 Process Instrumentation and Control Instrumentation and control at the BRWTF is similar to the BWTF. As at BWTF, process control is manual except for a handful of chemical feed systems as previously noted which are all controlled automatically (primarily flow paced), from PLCs. The SCADA system provides for remote monitoring of chemical systems and records plant operating data in great detail. The plant's online process analyzer instruments and data collection through SCADA have improved such that several process parameters reported to the State are taken from the plant SCADA system rather than from laboratory data. The City has indicated that instrumentation equipment is currently up to date and no further upgrades are desired at this time. Plant operating staff indicated the need for automation of chemical systems. The desire to automate plant operation to permit unmanned operation for at least a portion of every day was discussed as a potentially effective way to eliminate staffing problems due to seasonal variations in treated water demand. The recent AWWA Peer Review study recommended plant automation upgrades to allow for extended periods of unmanned operations. A cost estimate compiled in 2009 estimated the cost of such upgrades at $43 Million. The City's in-house programming and integration capabilities allow for continuous modifications to the plant control systems, and periodic automation features to be added when instrumentation hardware is available without the need to outsource the work. Plant influent flow is measured by a new magnetic flow meter installed in 2010 in the plant main influent line located in a vault in the yard. A streaming current monitor is installed in the piping ahead of the flocculation/clarification basins to provide data on performance of the coagulation process and is reported by staff to work well. The DAF system, placed into service in 2005, is PLC controlled while it is running. The system must be started manually, and is capable of automatic shutdown, but the influent flow must be stopped manually. Settled water turbidity is measured on the effluent from each individual DAF train. Individual turbidity meters and particle counters are installed on each filter effluent. These are reported to give acceptable results but the operating staff indicated that given the increasing importance being placed on finished water turbidity, supplementing the existing meters with laser turbidity meters and particle counters would provide better resolution at very low turbidities and allow better assessment of filter performance. Flow through individual filters is measured by flow tubes in the filter effluent piping. The flow to each filter is controlled by electric-motor-actuated butterfly valves. Filter backwashing is currently done manually- A venturi type meter is used to measure plant effluent discharged to the distribution system. Plant staff has indicated that this meter has not functioned well at times and requires periodic maintenance to maintain any level of accuracy; however, in the 2010 Mid-Term Improvements staff opted to replace the influent flow meter as they felt it was of greater importance. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-44 5.1.2.11 Plant Hydraulics The hydraulic capacity of the process piping and channels was evaluated from the hydraulic jump at the head of the plant to the treated water storage reservoir as part of the 2000 master plan and as part of the project upgrades in 2004. This analysis found that the existing facilities can pass a peak flow of 20 MGD without hydraulic restriction. The concerns with regard to the hydraulics at the hydraulic jump have since been eliminated when the hydraulic jump was replaced with piping in 2005. The DAF splitter box and all piping and components upstream of that box were designed for 20 MGD capacity. 5.1.2.12 BRWTF Treatment Capacity The results of the evaluation of major unit processes and systems of the BRWTF are summarized in Table 5-30. This evaluation indicates that the BRWTF currently has the firm capacity to treat 20 MGD to the level required to meet current regulatory requirements. Capacity is limited by multiple processes. Process Criteria Rated Potential Comments Capacity Capacity Raw Water Pipe Hydraulic Capacity 30 MGD 30 MGD Firm capacity with 28 MGD Conveyance Raw Water Pumping 20 MGD 28 MGD installed. Assumes one more 8 MGD pump can be added. Coagulation Hydraulic Capacity 20 MGD 20 MGD Flocculation/ Clarified water turbidity below DAF Surface Loading Rate 20 MGD 20 MGD 1.0 NTU more than 95 percent of the time. Filtration Hydraulic Loading Rate = 5 gpm/ft2 20 MGD 20 MGD Allows for one filter off line for backwashing. Sodium Hypochlorite at 5 mg/L 20 MGD 20 MGD To meet CDPHE requirements. Disinfection 85 MGD 85 MGD Chlorine Contact Time = 30 minutes minimum 16.9 16.9 To meet City's Goals MGD MGD Firm capacity with 24 MGD Finished Water Conveyance Finished Water Pumping 20 MGD 20 MGD installed. All pumps are constant speed. 5.1.2.13 Miscellaneous As with many facilities, the BRWTF is susceptible to periodic power outages. The plant currently has only a single power feed from the grid, and one emergency generator which lack the capacity to run the plant in even a limited fashion. Under the condition that the BWTF is unable to produce water, and power is lost at the BRWTF, the City is at risk of being unable to maintain water supply to the City. Two alternatives exist which can be evaluated to determine the most appropriate solution; either a second power feed can be routed to the plant from a different utility substation or additional engine driven generators can be installed to produce the required power. The BRWTF currently has a firm capacity to treat 20 MGD, but according to plant staff, the facility has only been run continuously up to 12 MGD, and has only momentarily been run at 16 MGD. It has been recently observed that the plant influent lines collect large amounts of sedimentation due to low velocities when running the plant at flows equal to or less than 8 MGD, such sedimentation is scoured from the pipes at 20 MGD flows making the water impossible to treat until the sediment passes. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-45 Also concerning to staff is the ability to pump 20 MGD into the distribution system. It has been reported that the last time 16 MGD was pumped into the system, several distribution mains were ruptured. It has been reported that improvements to the distribution system have been made since this attempt, but further attempts to test the capacity of the distribution system have not occurred. Related to the previous concern is the ability to pump water from Zone 2 to Zone 3. Equipment is in place to perform this operation, but it is reported that this system has not been fully or regularly tested to determine the actual capabilities of this system. Regular testing of the facility's ability to produce and distribute 20 MGD would benefit the City in that staff would become more familiar with the procedures required to perform such an operation and when faced with an unexpected failure at BWTF and the need to bring the BRWTF to full capacity they would be able to do so in an organized and expedient manner. Miscellaneous security improvements have been identified and recommended by the Vulnerability Assessment in 2008. 5.1.2.14 Chemical and Energy Efficiency Patterns Chemical usage varies due to seasonal and source water quality changes. Discussions with staff indicate that the City makes significant efforts towards chemical optimization. Continued monitoring, optimization, and experimentation efforts will likely lead to further improvements with regard to chemical efficiency. Chemical efficiency can also be improved through the automation of various chemical feed systems found throughout the plant, with the addition of PLC controlled flow pacing and trim capability. Utilizing feedback from process controls instruments, continuous adjustments can be made automatically through the PLC logic in order to consistently provide the proper chemical doses at all times. Improvements are needed to improve the flash mixing at the filter effluent post flume in order to further optimize the effect of the finished water chemical addition- Energy efficiency has been gradually improved over time with the use of higher efficiency pumps, premium efficiency motors, etc., as the technology and consciousness of efficient designs progress. Perhaps the single largest potential for energy savings exists with improvements to the High Service Pump Station. A study should be conducted to evaluate the performance of the existing high service pumps with regard to the hydraulic efficiency of the pumps and cavitation issues that have been identified. This study should also include an evaluation of the potential energy savings related to placing these pumps on variable frequency drives. 5.1.2.15 O&M Procedures and Maintenance Programs Based upon site visits and discussions with O&M staff, there is some room for improvement with regard to the completion of routine maintenance operations. Budgetary and manpower limitations generally limit maintenance activities to those items with mid to high priority, leaving items with low to mid priority unattended to. Fortunately, many systems at the BRWTF are five years old and less. It should be expected that as the equipment and facilities age, maintenance needs will increase, and there could be a need for additional budget and manpower to properly maintain the facility and avoid premature replacement of equipment. The City is in the progress of transitioning toward the use of computerized maintenance management software. This system will allow the City to more easily schedule and plan for routine maintenance activities. It is reported that a large commitment of time is required to enter all the necessary data for the system to become fully functional, and it is likely to be several years before the system is fully functional- City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-46 5.1.2.16 Needs for Continued Water Quality Compliance At this time there appears to be no shortcomings related to water quality compliance at BRWTF. 5.1.2.17 Future Water Quality Issues As discussed previously in Section 4.5, a study conducted by Black and Veatch in 2003 concluded that a second phase study needs to be conducted to evaluate two viable alternatives for mitigating the source water challenges. As further discussed in Section 5.1.3, if future regulatory limits with regard to DBP's are significantly lowered, the City may not be able to meet those limits. TOC removal should be enhanced by the recently installed carbonic acid feed system, but since there is limited data available since this system was installed, it is unclear at this time if further systems such as preoxidation with chlorine dioxide will be required to meet more stringent DBP limits. In the late summer of 2010, the City noted a dramatic increase in bluegreen algae (Anabaena planctonica, Aphanizomneon gracile, Aphanizomneom flos-aquae, and Lyngbya Iimnetica) from the Boulder Reservoir source. The bluegreens in the August sample comprised 10% of the total phytoplankton biovolume, up from 0.6% in July. Bluegreens are notorious for producing earthy, musty, and dirty tastes in drinking water. Section 3 presented a detailed discussion of the current and pending regulations that establish the water quality standards that water supplied by the City of Boulder must meet. The City is currently in full compliance with all existing regulations. Available monitoring data indicate that continued compliance with regulatory limits for inorganic chemicals (IOCs), synthetic organic chemicals (SOCs), volatile organic chemicals (VOCs), and radionuclides should not require either facility improvements or operational changes. The following sections present the results of evaluation of the performance of the City's existing facilities in meeting specific regulatory requirements in the future. This evaluation is based on operating data from 2004-2009. 5.1.3.1 Microbiological Contaminants Boulder's raw water supply originates entirely from surface water. As such, the system is regulated under the Surface Water Treatment Rule of the Safe Drinking Water Act. This regulation requires that the City's water treatment system achieve a minimum 99.9 percent (3-log) combined removal/inactivation of Giardia and a 99.99 percent (4-log) removal/inactivation of viruses. The IESWTR amends the existing SWTR Rule to strengthen microbial protection, including provisions specifically to address Cryptosporidium, and to address risk trade-offs with disinfection byproducts. The IESWTR went into effect in December 2001. Under the IESWTR the City has to achieve a minimum 99.0 percent (2-log) removal of Cryptosporidium, while continuing to meet existing SWTR requirements for Giardia and viruses. Filtered water turbidity is the treatment performance parameter used to measure compliance with both the SWTR and IESWTR. This parameter provides a direct, easily measured indicator of physical removal of pathogens by sedimentation and filtration. At the time the SWTR was promulgated, monitoring directly for human pathogens was determined by USEPA to be beyond the capability of many public water suppliers. Therefore, turbidity was selected as the best surrogate parameter to measure the removal of potential microbiological contaminants. The SWTR turbidity standard requires that at least 95 percent of the composite filtered water have turbidity below 0.5 NTU every month based on measurements made every four hours and that turbidity never exceed 5.0 NTU. As long as these turbidity standards are met, conventional treatment as practiced at the City's treatment plants is assumed to remove 99.7 percent (2.5 logs) of Giardia and 99.0 percent (2.0-log) of viruses. The remaining fraction of the required total City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-47 removal/inactivation for Giardia and viruses (0.5-log and 2.0-log, respectively), must be achieved through disinfection. The ISWTR will lower the turbidity limits to 0.3 NTU monthly average and the not to exceed maximum to 1.0 NTU to provide a 99.0 percent (2-log) removal of Cryptosporidium. The City of Boulder has developed a set of interim internal operating standards to ensure compliance with regulations and optimize removal of pathogens. The City's current target values for settled and filtered water turbidity are 1.0 NTU and 0.1 NTU, respectively, significantly more stringent than the regulatory requirements. Comparison of measured turbidities with these goals provides a mechanism for initiating corrective actions well before the regulatory turbidity standard is exceeded. The establishment of these more stringent goals also has aided operating personnel in the optimization of process performance. The settled water turbidity goal is used to optimize the flocculation and sedimentation processes prior to filtration. The daily average finished water turbidity values from 2004 to 2009 indicate that both the BWTF and BRWTF consistently met the SWTR turbidity standards currently in effect, at current water production levels and with current operating practices. Finished water turbidity levels are also consistently below the 0.3 NTU monthly average and 1.0 NTU maximum turbidity levels required under the IESWTR. Figures 5-31 through 5-38 depict the turbidity levels reported at each of the City's water treatment facilities from 2004 to 2009. These data substantiate that the water produced by the City's treatment facilities consistently meets both current and upcoming regulatory limits. 2.00 1.80 + 1.69 r 1.49 1.20 + ♦ r r 1.0o - • 44 4 -,b a. • 0.89 ~ f a i e ` !k _ 0.60 -'tip ~'!►i t. r~~€ ~ .v'v ~ty~~ i ' ~ ~1 C ~y~. 0.40 0.20 - 0.00 9/1/02 1/14/04 5/28/05 10110/06 2/22/08 7/6/09 11/18/10 Basin #1 Settled Turbidity • Basin 92 Settled Turbidity • Basin #3 Settled Turbidity Basin t#4 Settled Turbidity City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-48 Figure 5-32: BWTF Settled Water Turbidity Probability Plot - 2005-2009 2,50 2.00 1.50 z Over 95% of values <1.0 1.00 F 0.50 0.00 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 -0.50 --f-Basin #1 Settled Turbidity -11-Basin #2 Settled Turbidity Basin #3 Settled Turbidity -3*-Basin #4 Settled Turbidity Figure 5-33: BW T F Filtered Water Turbidity - 2005-2009 035 0.3 + + 0.25 z 0.2 + T 0.15 3 t + + 0.05 NOW 9/5105 3/24/06 10110/06 4J28107 11114107 611/08 12/18108 7/6/09 1/22110 8/10/10 • Filter N1 Turbidity • Filter #2 Turbidity Filter #3 Turbidity • Filter #4 Turbidity • Filter #5 Turbidity Filter #6 Turbidity Filter #7 Turbidrty Filter Turbidity Fib+.i 5-34: BWTF Filtered water -r urbidity Probability Plot - 2UU5-2UU9 0-200 0.180 0-160 _ 0.140 - 0.120 0.100 - Over 99% of values <0.1 ~ 0.080 - ~ F o F ~ 0.660 0.040 0.020 O.ooo 0 0-1 0-2 03 0.4 O.S 0-6 0.7 0.8 0.9 1 -*-Filter #1 TurbidrtytFrlter #2 Turbidity Filter #3 Turbidity }(Filter 44 Turbrdity -W-Filter #5 Turbidrty---Frlter#6Turbidity Filter 97 Turbidity Filter 08 Turbidity City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-49 Figure 5-35: BRWTF Settled Water Turbidity - 2005-2009 3 • 2.5 • ' a 2 • z • } • + • • .e 1.5 ~ • a ~ r 4 . • 1 j i4 ♦ ~ ~ _ ♦ t • • 0.5 a , 2117/2005 9/5/2005 3/24/2006 10110/2006 4/28/2007 11/1412007 611/2008 12/18/2008 7/6/2009 1/2212010 • DAF #1 Turbidity Avg • DAF #2 Turbidity Avg Ficiure 5-36: BRWTF Settled Water Turbidity Probability Plot - 2005-2009 s 4.5 4 3.5 - 3 DAF #1: 951/. below 0.81 NTU DAF #2:95% below 0.61 NTU 2 1.5 1 0.5 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 --o-DAFttl Turbidly -s-DAF 02 Turbidity City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-50 s 5-37: BRWTF Filter Turbidity - 2004-2009 0.2s 02 - 416 m h -t 0.15 ♦ s 41 • a 1 40 4. 9 i 0.05 a Yx J w ( _ yr r,yV~ - ir-- 4 V 2/17/2005 9/512005 3124/2006 10/10/2006 4/2812007 11114/2007 611/2008 12/18/2008 716/2009 1/2212010 •Filter#1TurbidityAvg +Filter#2TurbAityAvg eHter#3TurbidityAvg .Filter #4 Turbidity Avg Figure 5-38: Boulder Reservoir WTF Filter Turbidity Probability Plot - 2005-2009 0.2 0.18 0.16 Filter #1: 95% below 0.086 NTU 0.14 Filter #2: 95% below 0.079 NTU Filter #3: 95% below 0.095 NTU 0'12 Filter #4: 95% below 0.11 NTU x' 0,1 ~a 3 0.0& H 0.06 0.04 0.02 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Filter#1 Turbidity -4--Filter#2Turbidity Filter #3 Turbidity Filter 94 Turbidity 5.1.3.2 Disinfection The SWTR contains three disinfection performance criteria: • Sufficient disinfection must be practiced prior to the first customer of the public water supplier to fulfill the required 3.0-log (99.9%) and 4.0-log (99.98%) removal/inactivation requirement for Giardia and viruses, respectively. • At all times, at least 0.2 mg/L of disinfectant residual must be present in the water leaving the water treatment plant. However, the chlorine residual must not exceed 4.0 mg/L. • A disinfectant residual must be present in at least 95 percent of samples collected in the distribution system at the same sites and frequency as the total coliform monitoring program. In cases where no residual disinfectant is detected, samples with heterotrophic bacteria counts less than 500 per milliliter (ml) may be considered as having a disinfectant residual present. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-51 Based on monitoring data from 2004 to 2009, the City is consistently in compliance with the disinfection requirements of the SWTR. Chlorine is used as the disinfectant and a residual in excess of 0.2 mg/L of free available chlorine has been present at all times in the water leaving both treatment plants. Figures 5-39 and 5-40 show that the chlorine residual in the finished water from the BWTF averages 1.2 mg/L and from the BRWTF typically ranges averages 1.15 mg/L. On-line continuous chlorine analyzers meet the monitoring requirements of the SWTR. Although City staff indicated some concern regarding compliance with increasingly stringent water quality criteria within the distribution system, based on the available data, detectable disinfection residuals are consistently found, and the heterotrophic bacteria levels are below 500 per ml with few exceptions. 1.9 - 1.7 E 1.5 v 1.3 1.1 ~ wow ~ * • ww-wllli L 0.9 0-7 Average = 1.21 mg/L 0-5 9/1/02 1/14/04 5/x8/05 10/10/06 2122108 7/6/09 11/18/10 + Betasso WTP -Betasso Average CL2 R=iqure 5-40: BRWTF Effluent Chlorine Residuals - 2004-2009 1.9 1.7 Average = 1.15 mg/L • 1.5 • 0 1:3 • o • + • U 019 i 0.7 • • 0.5 9/1/02 1/14104 S/28/05 14/10/06 2/22108 7/6/09 11/18/10 -Boulder Reservoir Average C12 + Boulder Reservoir WTP City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-52 To meet the 0.5-log and 2.0-log inactivation requirements for Giardia and viruses, the USEPA requires that minimum CT (concentration x time) requirements be met. The contact time required to achieve the required inactivations vary depending on the temperature, pH and degree of inactivation required. CDPHE administers this requirement by stipulating that all water providers with surface water supplies that use conventional treatment processes must provide at least 30 minutes of actual contact time following filtration. The available contact time following filtration is calculated using peak design flow and the total volume of treated water storage prior to the first customer, including tanks and pipelines. Tank volume is adjusted by a factor that relates storage tank hydraulic configuration to theoretical contact time. This factor ranges from 0.1 for unbaffled storage tanks to 0.7 for tanks with very good baffling. A factor of 1.0 is applied to the volume in a pipeline. As discussed previously, both treatment plants have adequate treated water storage volume to provide the minimum 30 minute contact time at their design peak flow rates. Estimating the actual CT required using USEPA guidelines indicates that under worst case temperature (0.5°C) and pH (8.0) conditions the contact time would be 51 minutes assuming a chlorine concentration of 1.0 mg/L. As the water temperature rises and the pH goes down, the CT value would reduce such that at water temperatures of 5°C and pH at 7.8 the CT would be about 34 minutes and at a temperature of 10°C the CT would be about 25 minutes. Again, both treatment plants have more than adequate storage tank and piping volume to exceed CDPHE disinfection contact time requirements at peak design flow rates. The treated water storage reservoirs at the BWTF have sufficient volume after derating to provide over 55 minutes of contact time at a flow rate of 50 MGD, sufficient to meet the worst case conditions. Some additional time would be provided in the plant piping. No credit is taken for time in the distribution piping because the first customer tap is within a short distance of the plant. Treated water storage reservoirs at BRWTF after derating have sufficient volume to provide over 120 minutes of contact time at a flow rate of 20 MGD, sufficient to meet the worst case conditions. 5.1.3.3 DBPs In the early 1970s, it was determined that the disinfection practices that had for many years provided protection against waterborne diseases resulting in dramatic improvements in public health can also impart chemical byproducts which are suspected of adverse chronic health consequences for people subjected to long-term exposures at low concentrations. Since then, the control of DBPs has been the subject of intense scrutiny by the regulatory, drinking water, and public health communities. In 1979, USEPA established a drinking water standard for total trihalomethanes; a group of four byproducts formed with free chlorine present. Still in effect, this standard requires a running annual average TTHM concentrations below 0.1 mg/L, based on quarterly samples collected at multiple locations in the distribution system. In December, 2001 under the Stage 1 D/DBPR the TTHM limit was lowered to 0.080 mg/L and the maximum contaminant limit for the HAAS was lowered to 0.060 mg/L. In the late 1990's the Information Collection Rule required large public water systems serving at least 100,000 people to monitor and collect data on microbial contaminants, disinfectants and DBPs for 18 months. The information collected from the study (which the City of Boulder participated in) resulted in the Stage 2 D/DBPR. This rule did not change the respective MCLs for TTHM and HAAS; but as of April 2012 the method of determining compliance will be based on a locational running annual average (LRAA) of the previous four quarters of samples at each approved distribution system compliance location, rather than an average across sampling points within the system. Figures 5-41 and 5-42 present the disinfection byproduct data for the Boulder distribution system sampling program, using the LRAA method, from November 2004 through November 2009. As can be seen on Figure 5-41, since October 2005 the LRAA concentrations for TTHMs were consistently below the regulatory limit of 0.080 mg/L (80 ppb). Similarly, the HAAS concentrations were consistently below the 0.060 mg/L limit. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-53 Figure 5-41: Boulder Distribution System TTHM for D/DBPR Compliance Points - Locational Running Annual Average vn a 100 L MCL-~0 ppb Rn 0 U x d m re 60 a' 3 c C d a0 d ~J G O 20 0 0 9/1/01 1/1/OS S/1105 9/1/05 111105 S11106 011/06 111/07 SJ1/07 9/1107 1/1108 S/1/08 9/1108 111/09 511109 9/1109 +Carpet One MR- DSMRT2 tlrlsCenter (Parks Admini:lration) -&-office oldg V 3oth & Baseline -LL1UI MR-USMRII -South Boulder Rec Center Waste Water treatment Plant Figure 5-42: Boulder Distribution System HAAS for D/DBPR Compliance Points - Locational Running Annual Average 120 n 100 a c 0 c v 80 a u a a = MCL = 60 ppb m v fi0 - a Q 3 c c Q m c 1 C 3 C C O 0 20 J 0 911104 111/05 511105 911105 111106 511/06 9/1106 111107 5/1107 9/1/D7 1/1/08 511108 9/1/08 1/1/09 511/09 911/09 -0--CarpetOneMR -DSMRT2 fIris Center [Parks Administration) fOtficeBldg @30th8:Baseline --CDOT MR - D5MRT1 -South Boulder Rec Center +Waste Water Treatment Plant City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-54 Figures 5-43 and 5-44 respectively present the TTHM and HAAS concentrations in the finished water from both plants- Both of the City's water treatment facilities have chlorine feed points in the process piping before (pre-chlorination) and after filtration (post-chlorination). Prior to summer 2006, the pre filtration chlorine was added to the raw water before flocculation and sedimentation. This practice has been linked to increased formation of DBPs through reaction with naturally occurring organic matter (NOM) present in the raw water. From the available historical data it is apparent that the elevated DBP levels coincide with the spring runoff period indicating the presence of greater concentrations of DBP precursors, primarily NOM. At the same time, raw water pH and alkalinity drop to lower than normal levels, which can affect the performance of the pre-treatment process with respect to removal of DBP precursors. In response to the observed high DBPs levels, particularly in the summer 2005 and 2006 periods, the City modified its disinfection practices to eliminate routine pre-chlorination and now applies free chlorine to the settled water. This change, as well as the increased control/optimization of the pre-treatment process through the use of streaming current monitors, has help stabilize the distribution system DBP levels and keep the City well within the compliance levels. It is important to note that optimizing the coagulation/flocculation/sedimentation processes for turbidity removal does not necessarily coincide with optimization of these processes for TOC removal. DBP formation can also be significantly affected by the operation of the distribution system. The kinetics of DBP formations are such that DBPs continue to form as long as the chlorine and precursors are in contact with each other. As a result, the length of time water remains in the distribution system after treatment has a direct influence on the concentration of DBPs formed. Operating practices that focus on maintaining maximum volumes in the storage reservoirs along with reported problems with moving water into and out of storage reservoirs can result in long detention times in the system that contribute to the elevation of DBP levels. Based on the data presented in this section, it is apparent that the majority of the DBPs are generated in the treatment process. While this implies that long residence times may not be a major contributor to DBP formation under current system operational practices, these operations should be carefully monitored and storage needs continuously balanced with water quality implications. If the regulatory limits are lowered significantly in the future, the City may not be able to comply. Should the running annual average limits be lowered to 0.040 mg/L for TTHMs and 0.030 mg/L for HAA5 as has been speculated, disinfection byproduct concentrations would need to be reduced well below current levels to achieve compliance. For a long-term vision of reducing the disinfection byproduct levels in the distribution system, the City should continue to investigate ways to improve the pre-treatment process for TOC removal, through bench scale and full-scale optimization studies, and evaluation of alternative disinfectants. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-55 -13: BWTF and BRWTF Effluent TTHM Concentrations 100 -HBetasso - Finished EP00001 90 --11--BRWTP@63 Finished EP00002 a 80 0. c 0 70 4+ m aci 60 u c 0 av, 50 c m s E 40 0 m r 30 IL m m 4.1 LJ F- 20 10 0 ~ ~~k.0 r, r r- r, r, o0 m x m m m m m m m 0 o 0 0 0 0 o 0 0 0 0 o 0 0 0 0 o 0 0 I 7 Q- > C 7 n- > C L 7 fl- > C L 3 > co m Q) 0 co m w 0 ro m v 0 m m N 0 vi Z 2: cn Z n Z ? 2-- r 0 CD O 0 0 O 0 0 0 O 0 0 O o 0 0 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-56 i-e _-1,44: BWTF and BRWTF Effluent HAAS Concentrations 100 90 -4-Betasso - Finished EP00001 Q 80 f13RWTP@63 Finished EP00002 O. c 0 70 Y M Y aci 60 u c O avi 50 c M L E 40 0 m E 30 m Y H 20 10 0 0 0 o 0 0 0 0 o 0 0 0 0 o 0 0 0 0 o 0 0 7 Q- > C - 7 n- > C L 7 Ll > C L Ei Q > m m a) O m m N O m f° v O m N O vi Z cn Z 7 n Z 2-- 0 CD CD rr o 0 0 O 0 0 0 O 0 0 o O 0 0 5.1.3.4 Lead and Copper Rule In 1991, USEPA promulgated the Lead and Copper Rule (LCR) requiring all large systems to demonstrate that optimal corrosion control treatment is being practiced at their facilities. To meet these requirements, the City practices chemical stabilization at both water treatment plants. The objective is to maintain the water within a chemically stable range by maintaining pH and calcium carbonate (CaCO3) alkalinity within specific limits such that metal ions will not be picked up by the water as it passes through pipes. To achieve this stability, a pH of 7.8 to 8.0 and an alkalinity of 35 to 40 mg/L as CaC03 were established as criteria for finished water. To meet these criteria, capital improvements were made at both water treatment plants to add or improve chemical feed systems. Since the raw water quality is different at each plant, different chemicals are used to attain the desired finished water stability. The raw water treated at BWTF is low in alkalinity. To raise the alkalinity to the target range, lime is added. C02 is added after the lime to stabilize pH within the target range. The C02 system was installed and the existing lime storage and feed equipment was replaced in 1996. At the BRWTF, an engineering predesign study determined that the raw water had sufficient alkalinity at all times so that chemical adjustment would not be needed. Caustic soda (sodium hydroxide, NaOH) was selected as the best chemical to use for pH adjustment. A caustic soda storage and feed system was installed along with other miscellaneous improvements in 1993. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-57 Figures 5-45 and 5-46 present finished water pH and alkalinity data from 2004 to 2009. It can be seen that both the pH and alkalinity of the BWTF treated water are, on average, within the target range, thereby meeting the requirements of the lead and copper rule. But, there is some variability, particularly in alkalinity. However, since effective corrosion control is a function of long-term average water characteristics, the short-term variations do not adversely affect the performance of the process. The variability in alkalinity does reflect the difficulty of controlling the lime feed system with precision as reported by plant operating staff, indicating a possible need for improvements to the lime mixing and feed equipment. Figure 5-45 indicates that although the pH of the finished water from the BRWTF is typically within the target range, control using NaOH is not as precise as it is at BWTF using lime and CO2. The lack of an alkalinity adjustment system is apparent from the wide variability in that parameter. Of particular concern is the difference in finished water alkalinity depending on whether raw water is being drawn from Boulder Reservoir or the BFC. Water drawn from the reservoir during the non summer months has more than adequate alkalinity and no further adjustment is needed for corrosion control. However, water taken from the canal has significantly lower alkalinity resulting in finished water alkalinity near or below the lower limit of the target range. In addition, the sharp change in alkalinity when the raw water source is switched causes problems for users with water quality sensitive industrial processes and has resulted in complaints from industrial customers. Figure 6-46: Svv f r anc bkvv fr° €-inistieco vva er pig - 2UU4-2UU9 9 8.5 - ; • • 8 • x a M t 7.5 7 - t + 6.5 9/1/02 1/14f04 5/28/05 10/10106 2/22/08 7/6/09 11/18/10 + Betasso WTP Finished pH + Boulder Reservoir WTP Finished pH City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-58 u: BWTF and BRWTF Finished Water Alkalinity - 2004-2009 120 • 100 + r • 80 + m • t E • X 60 m t • s ~ 40 20 o - 911102 1/14/04 5/28/Os 10/10/06 2/22/08 7/6/09 11/18/10 ♦ Betasso WTP Finished Alkalinity • Boulder Reservoir WTP Finished Alkalinity 5.1.3.5 Sanitary Survey CDPHE completes a Sanitary Survey of each of the water treatment facilities in Colorado every 3-5 years, depending on performance. The City of Boulder recently received a letter from CDPHE, dated September 22, 2010 summarizing the results of this Sanitary Survey. The deficiencies found were categorized into significant deficiencies and minor deficiencies and are discussed in the sections below: Significant Deficiencies (must be fixed and reported to CDPHE) • Betasso WTF - the clearwell vents were not protected with a 24-mesh non-corrodible screen to exclude insects, birds, and animals • Kohler Storage Reservoir - the roof penetrations are exposed and not protected with a 24-mesh non-corrodible screen to exclude insects, birds, and animals • Booton Storage Reservoir - the access hatch was not designed to prevent contamination from entering the tank. The new flush-fitting hatch lids were not sealed with a gasket, or did not overlap the framed opening and extend down around the frame at least 2 inches. Minor Deficiencies (must be fixed and reported to CDPHE) • Booton Storage Reservoir - storage facility openings were protected with a coarse screen, but must have a 24-mesh non-corrodible screen or a flap valve to prevent entrance of contaminants. • Gunbarrel Storage Reservoir - overflow pipe does not terminate 12 to 24 inches above a splash pad and needs to be extended to prevent erosion of the foundation soil at the base of the tank. • Maxwell Storage Reservoir - storage facility openings need to be protected with a 24-mesh non- corrodible screen or flap valve to prevent entrance of contaminants. • Devils Thumb Storage Reservoir - all storage facility openings were protected with a coarse screen, but must have a 24-mesh non-corrodible screen or a flap valve to prevent entrance of contaminants. Also the overflow pipe does not terminate 12 to 24 inches above a splash pad and needs to be extended to prevent erosion of the foundation soil at the base of the tank. • Kohler Storage Reservoir - storage facility openings need to be protected with a 24-mesh non- corrodible screen or flap valve to prevent entrance of contaminants. • Chautauqua Storage Reservoir - storage facility overflow pipe needs to be protected with a 24- mesh non-corrodible screen or flap valve to prevent entrance of contaminants City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-59 There were no monitoring violations or MCL violations during the past year, however there was one violation listed: Violation No. 109, Date = 3/10/2010, Type: Single Combined Filter Effluent (IESW7R/LT1), Compliance Period 1/1/2010 - 1/31/2010. This violation has been responded to with the Compliance Assurance section- Other Observations/Recommendations/Comments include. • The distribution system operator should have an operator Level 3 certification. The current distribution system operator in charge is a Level 4, however compliance with this regulation is noted. • Free residual chlorine at the extremity of the system was measured as 0.2 mg/L, which is in compliance. • Chautauqua Reservoir's roof vents terminated in an inverted 'U' construction with the openings less than 12-inches above the roof surface. The WQCD recommends a distance of more than 12- inches. In addition, there is graffiti on the side of one of the distribution system tanks along with stones on the roof indicating a breach in security. • BRWTF's and BWTF's fluoridation systems were inspected and are in compliance with the requirements. 5.2 Distribution System Facilities This section evaluates the major distribution system facilities owned by the City. The distribution system was evaluated based upon on-site observations, information provided by operating staff, and information collected from previous reports. Computer modeling was used to assess distribution system performance and identify deficiencies. The distribution system was modeled to simulate the system hydraulics. This summary is presented in Section 5.2.7 and the hydraulic model is included in Appendix C. A discussion of the major pipelines is included here. The Boulder Canyon pipeline was originally built in the late 1800s. Improvements made to the pipeline in the early 2000's including removing the Fourmile PRV station and repairing the 16-inch zone 2 line have resolved many of the deficiencies in this area. Several leaks have been identified on the 24-inch Boulder Canyon Pipeline between the Orodell Hydro/PRV station and the old Fourmile PRV station. This section of pipe is planned to be replaced in the near future. Testing of the pipeline, completed in 2008 demonstrated that the pipeline can carry at least 17 MGD. The design flow of the pipeline is 20 MGD. The Sunshine pipeline is the primary transmission main for carrying water from the BWTF to the City. No deficiencies were noted with this pipeline. Improvements in 2005 to the distribution system from BRWTF included a new, 24-inch pipeline along the Diagonal Highway to the improved Iris Pump station allowing BRWTF to deliver up to 12 MGD. Further improvements, completed in 2010 included a "sister" pump station, Iris #2 and the replacement of the pumps at the Cherryvale pump station. These improvements increased the capacity of the system to 20 MGD to be supplied out of BRWTF. Out of the 20 MGD delivered from BRWTF, 3.4 MGD goes to Zone 1 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-60 and 12.7 MGD can be delivered to the Iris #1, Iris #2, and Cherryvale Pump Stations for delivery to Zone 2. The remainder of the flow is required to be pumped from Zone 2 to Zone 3 in order to realize the 20 MGD capacity of the BRWTF. No further capacity improvements to the Zone 1 system have been identified. Similarly, no deficiencies were identified in the transmission piping that carries all water from the BRWTF to the Zone 1 distribution system. Computer modeling did, however, indicate problems with some of the Zone 3 transmission mains that feed the Zone 3 tanks. This is discussed in more detail below in the section on Treated Water Storage. The design conditions limit the flow from BRWTF to 16.1 MGD when only Zones 1 and 2 are being fed from BRWTF. Currently up to 3.4 MGD goes directly to Zone 1 while the other 12.7 MGD goes through the pump stations at Iris and Cherryvale to Zone 2. In the event that the BRWTF is required to provide water to Zone 3, the new Iris #2 pump station and the new distribution pipeline along the Diagonal allows for the potential capacity up to 20 MGD that can be delivered to Zone 1 and Zone 1 pump stations, then from Zone 2 to Zone 3 from BRWTF, matching the plant capacity. Additional pumps within the system are able to transfer water from Zone 2 to Zone 3. A standard operating procedure for this transfer exists, but more frequent testing of this procedure is recommended. The city's distribution system has four hydroelectric power generating facilities. These facilities allow the recovery of a significant amount of energy from the excess pressure available in the treated water distribution system. A condition assessment was made for the four facilities and is included in Appendix D. The following is a summary of that inspection report. Overall recommendations include that a master equipment list be generated for each facility including manufacturer details, date of install, date of last service, maintenance interval, and any other special information. 5.2.2.1 Orodell Hydroelectric Station and PRV The Orodell Hydroelectric Station's turbine/generator, turbine isolation plug valve, downstream flow control valve, upstream butterfly valves, bypass PRV valve, and miscellaneous valves and piping are all reported to be fair to good. In poor condition are the bypass downstream isolation butterfly valve and the battery backup and charging system for instrumentation and control. 5.2.2.2 Sunshine Hydroelectric Station and Flow Control Facility The Sunshine Station's system equipment is all reported as good to fair. No improvements are needed at this time. The PRV is located in a separate vault and reportedly needs attention. The PRV needs rehabilitation or replacement of the control system. In addition, a flow meter needs to be replaced for the facility's 30-inch pipeline. 5.2.2.3 Maxwell Pump Station and Hydroelectric Plant The overall rating for this facility was GOOD (Rating = 2). Individual components were rated as fair to good. 5.2.2.4 Kohler Hydroelectric Station and Flow Control Facility The overall rating for this facility was FAIR (Rating = 3). Individual components were rated as fair to good. 5.2.2.5 Kohler and Maxwell Emergency Pump Mode The Kohler and Maxwell Hydroelectric Stations are typically used to break pressure and generate electricity between pressure Zones 3 and 2. However, these facilities are set up to operate in pumping mode to supply flow to Zone 3 in case of an emergency or drought. Tests of this emergency mode were performed and summarized in a City of Boulder report in August 2009. The report found that a supply of 3.7 MGD to zone 3 was required during emergency situations. The pump tests found that a total of 4.23 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-61 MGD can be produced by Maxwell and Kohler, and if the Maxwell turbine were rebuilt or replaced, the total capacity would be roughly 4.7 MGD. Therefore, sufficient capacity is available from Zone 2 to 3. There are a total of seven operating pressure reducing valve stations in the Boulder distribution system- Four of these control bypass flows at the Orodell, Sunshine, Kohler and Maxwell hydroelectric generating stations. All of these valves are rated in fair to good condition. The PRVs throughout the system are used as needed based on production at the two plants and overall system demands. The remaining PRVs are as follows. 5.2.3.1 101 Pearl PRV The PRV station at 101 Pearl is primarily used only when a large amount of water has to be moved from Zone 3 to Zone 2. This usually occurs during high demand/production periods in the summer. 101 Pearl is rarely used at any other time since it in essence takes water somewhat directly from BWTF and pushes it into Zone 2, where it is used without greatly impacting the reservoirs in either Zone 3 or 2. Operations have observed that use of this station during low demand periods results in decreasing chlorine residuals in the north and south ends of Zone 3 in particular. However it also seems to have some impacts resulting in increased water age in the north and south ends of Zone 2. This station used to be used more frequently throughout the year. Since changing its operation so that it is primarily used only in high demand situations, there has been a decrease in the number of low chlorine events in both Zone 3 and 2. A general scenario in which 101 Pearl would be used is as follows. BWTF is producing a large volume of water daily, resulting in a need to pass a significant volume of water from Zone 3 to Zone 2. Operators maximize use of the Maxwell and Kohler Hydro stations; first all generators are started to maximize generation before also using PRVs. If additional water needs to be moved into Zone 2 from 3 then operators use the PRV valves at each hydro station first. Often in this situation Kohler and Maxwell stations are each passing 6-8+ MGD using the hydro and the PRV bypasses. If high volumes of water are going through both stations but more still needs to be moved, operators begin using 101 Pearl to pass additional water. 101 Pearl is operated using a downstream PSI set point from which the valve automatically regulates to maintain the pressure set point. The pressure set point is increased sufficiently to result in the station passing enough water to obtain the desired results in both Zone 3 and 2. The 101 Pearl Street PRV Station building is in good shape, with the exception of a potential for grading improvement and a gravel or concrete pad for the parking/turn around area. Equipment in the 101 Pearl Street PRV Station includes PRV valves, isolation butterfly valves, and the I&C system. All mechanical equipment is in good condition with no reported problems. The PRV is rated in GOOD (Rating = 2) condition and no further work is expected. 5.2.3.2 Cherryvale and Iris PRVs Valves at Cherryvale and Iris #1 and #2 are operated as needed when water must be passed from Zone 2 into Zone 1. This occurs either when the BRWTF is not producing enough to meet the demand in Zone 1 or when the BRWTF is offline. Typically the 2 inch valves are opened first. Then if additional flow is needed the 8 inch `Main' valves are opened. The main valves operate on a downstream pressure control system. If downstream pressure gets too high they will modulate themselves closed. The Cherryvale main valve has a downstream pressure setting of approximately 65 PSI, and the Iris main valve has a setting of about 55 PSI. These settings are intended to be set low enough such that zone 1 pressures would cause the valves to close before the Gunbarrel Tank overflows. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-62 The pump stations in the distribution system were not evaluated as part of this TWMP. The pump stations include: • BRWTF Pump Station - recently refurbished • Iris #1 Pump Station - refurbished with new pumps in 2005 • Iris #2 Pump Station - new (built in 2010) • Cherryvale Pump Station - upgraded with new pumps in 2010 • NCAR Pump Station - condition unknown, private system • Maxwell Pump Station - evaluated with the hydroelectric facility. Rated in good condition (see Appendix D) • Kohler Pump Station - evaluated with the hydroelectric facility. Rated in good condition (see Appendix D) The City has 6 treated water storage reservoirs serving the three pressure zones. A structural evaluation and hydraulic capacity evaluation is discussed in this subsection. 5.2.5.1 Previous Evaluations A report was compiled by Black & Veatch in June 2002, titled Report on Chautauqua, Kohler, and Maxwell Reservoirs, which investigated the general physical condition of each reservoir through leak testing and underwater inspections. The report also summarizes various lining alternatives to reduce leakage at each reservoir. A second report was compiled by Rooftech in October 2007, titled Roof Inspection Report, which detailed the condition of the Kohler Reservoir roof and recommended improvements. All significant findings and recommendations of these reports are included in the facilities evaluations below. 5.2.5.2 Preliminary Structural Evaluation A preliminary structural evaluation was performed by MWH for the six (6) water storage reservoirs in May of 2010. The inspection was to assess the overall condition of the reservoirs for asset management planning and to identify any major replacement costs that might be required within the next 20 years. The inspections were limited to a preliminary condition assessment based on visual judgment and did not allow for any in depth inspections. The inspection report is included in Appendix E and summarized below. x.2,1 Max,,,vell Reservoir Maxwell Reservoir is of 360 feet x 200 feet with a capacity of 9.5 MG. The reservoir is covered with concrete double tees supported by concrete beams and columns. The double tees are covered with insulation and topped with asphalt and gravel. The perimeter of the reservoir sticks above the finished grade approximately 5 feet and slopes in the shorter dimension up to the center at approximately a 1.5 percent slope. The following list was generated describing the external items that need attention and should be maintained on a regular basis: • Longitudinal crack close to the Southeast corner of the reservoir should be inspected further for the potential causes of the crack and a repair procedure should be developed before the winter season. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-63 • Eroded soil areas along the perimeter of the reservoir should be inspected further for the cause of the erosion and a repair procedure should be implemented. Suggest replacing the grass/soil adjacent to the structure with free draining gravel to help with erosion. • Construction and movement joints at the corners and at the midpoint of the North and South walls of the reservoir should be sealed from external weather before the winter season. • The layout surrounding the reservoir ground access area should be investigated and a re-grading solution should be developed and implemented. The steel enclosure should be re-coated and the joints re-sealed. • The roof at a minimum should be recoated or a new roof system should be developed to minimize trapping moisture against the concrete double tees. • All coated surfaces should be analyzed to determine the current condition is adequate to prevent corrosion for external elements. Form the current visual inspection, there are many areas that need to be re-coated. • The CMU Crack at the Hydro building should be inspected further to determine the cause and a repair procedure should be developed and implemented prior to further deterioration. • The 2002 Rooftech report found that the Maxwell Reservoir exhibited significant leakage and deterioration of the existing composite asphalt lining system. 5.2.5.2.2 Kohler Reservoir Kohler Reservoir is 330 feet x 230 feet with a capacity of 9.4 MG. The reservoir is very similar to the Maxwell reservoir but is covered with a metal deck roof supported by metal purlins. The metal roof is galvanized steel that has been coated with paint. The reservoir sticks above ground, at the low point, approximately 4 feet with metal decking covering the concrete wall portion that is above grade. The following list describes the external items that need attention and should be maintained on a regular basis. • A Roof Inspection Report for the Kohler Reservoir was compiled in October 2007. The report found that the roof panels were originally coated with a green, latex-type coating. The coating is in very poor condition, with shrinkage cracks and paint peeling throughout, as well as some surface rust below the paint. • The existing roof system consists of 24-gauge galvanized steel panels supported by C-purlins spaced approximately 5'-9" on center, attached with exposed fasteners having rubber washers. The roof panels are somewhat unusual; they only span two purlins, while most roof panels are designed to span a minimum of three purlins. This construction significantly reduces the structural capacity of the panel, and is likely contributing to the numerous buckled panels throughout the roof. The roof is in poor condition and is at the end of its design life cycle. However, the roof is not as likely to leak consistently as is the Chautauqua Reservoir. • Joints in the concrete walls that have opened up due to wall movements should be sealed and protected from external weather. This is necessary to prevent future erosion problems. • Coating system on the gutter between roofs has failed and the condition of the gutter should be evaluated to determine if it should be replaced or re-coated. • Vegetation around the reservoir should be removed and the top layer of soil replaced with free draining material. The finished grade along the reservoir should also be regarded to allow drainage away from the reservoir. This was completed in 2010. • The 2002 Rooftech report found that the Kohler Reservoir exhibited significant leakage and deterioration of the existing composite asphalt lining system. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-64 5.2.5.2.3 Devil's Thumb Reservoir Devil's Thumb Reservoir is 102 feet and a capacity of 5.0 MG. The reservoir is an above grade steel tank that sits on a concrete slab-on-grade with a thickened edge. The tank is roughly 20 feet tall with the roof sloping from the center to the outside edge. Along the perimeter of the tank is a metal rain guard that is approximately 12 feet above the ground and protrudes 1 to 1'/ feet. The following list describes the known items that need attention and should be maintained on a regular basis. • Rock pits surrounding the tank should be cleaned and re-coated on an annual basis. • Finished Grade around the back side of the tank should be re-graded to allow proper drainage of the site. • Rocks need to be removed from the roof. • Further investigation into why the tank roof is dented and deformed is needed to identify if the possibility of the roof collapsing or failing in the near future exists. • Concrete foundation needs to be protected or repaired. • Vegetation next to the tank needs to be removed. • Rain guard might need to be installed facing the opposite direction, further investigation is needed. • Internal coating needs to be removed and re-coated because it contains lead. 5.2.5.2.4 Chautauqua Reservoir Chautauqua Reservoir is in the shape of a trapezoid. The base is approximately 250 feet with a top dimension of approximately 180 feet and edges with a length of approximately 260 feet each. The capacity is listed as 8.0 MG. The following list describes the items that need attention and should be maintained on a regular basis. • Perimeter wall shrinkage cracks should be "V" grooved and sealed to prevent future erosion. • Built up roof system has failed and needs replacing. Suggest considering a separate roof system that isolates the roof from the concrete double tees. • Roof vents need to be re-coated. • Further investigation of the internal concrete lining should be conducted to determine the condition and remaining service life. The leaking joints can lead to problems along the perimeter of the structure including settlement issues and possible contamination of the reservoir. • Further investigation of the double tee shear tabs is needed to determine if the roof can perform as originally designed. New tabs might be needed, or the entire roof might need to be replaced. • The 2002 Rooftech report found that the Chautauqua Reservoir exhibited significant leakage. 5. .x,.2.5 Booton Reservoir Booton Reservoir is a tank within a tank. The external tank is 173-foot-diameter and the internal tank is 68-feet-diameter with a capacity of 0.6 MG. Both tanks are pre-stressed concrete tanks that are completely below grade. The reservoir was not accessible for inspections therefore the condition of the buried tanks are unknown. These tanks were constructed within the last 20 years and the City staff has indicated that they have had no problems, so it is assumed that the tanks are in good condition. Regular inspections should be performed to verify the tanks are performing as designed. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-65 5.2.5.2 .6 (3unbarrel Reservoir Gunbarrel Reservoir is an above ground steel tank with a plan diameter of 130 feet and a capacity of 2 MG. The tank is approximately 20 feet tall with a roof that overhangs the side walls by 4 feet. The following list describes the items that need attention and should be maintained on a regular basis. • Rock pits should be cleaned and re-coated on an annual basis. • Vegetation should be kept from growing over the slab-on-grade and ultimately the adjacent soil should be removed and replaced with weed barrier and free draining rock. • The bird nests and excrement should be removed from behind the soffit and along the tank. After cleaning the area, bird screens or wire mesh should be installed between the soffit and the roof overhang to keep birds from nesting behind the soffit. • Investigate the purpose of the external box that might contain a corrosion protection device. 5.2.5.3 Reservoir Capacity Evaluation The storage reservoirs are evaluated to determine whether there is sufficient storage capacity to meet projected, future demands. 5.2.5.3.1 Reservoir Storage Criteria The total storage required for a water system is evaluated in three parts: 1) storage for operational use 2) storage for fire fighting and 3) storage for emergencies. These three components are determined by pressure zone in order to evaluate the ability of the water system to meet the storage criteria on both a zone-by-zone basis as well as a system-wide basis. These three storage components are discussed in more detail below. 5.2.5.3.2 "'perational Storage Operational storage is defined as the quantity of water that is required to balance daily fluctuations in demand and water production. It is necessary to coordinate the water source production rates and the available storage capacity in a water system to provide a continuous treated water supply to the system. Water systems are often designed to supply the average demand on the maximum day and use reservoir storage to supply water for peak hour flows that typically occur in the mornings and late afternoons. This operational storage is replenished during off-peak hours that typically occur during nighttime, when the demand is less. AWWA recommends that an operational supply volume ranging from one-quarter to one-third of the demand experienced during one maximum day. It is recommended that each pressure zone in the City's water system have an operational storage of at least 25 percent of MDD. The criterion for the operational storage is consistent with the 2000 TWMP. 5."x.5.3.' I i,e Flow Storage Fire flow rates and durations for various types of development are given in Table 5-31 together with the storage volume required to meet these demands. In applying these standards, the worst case of fire flow is assumed for each zone. For example, if the highest fire flow of a zone is 6,000 gpm for duration of 4 hours, the required storage for that zone is 1.44 MG. For analysis purposes, it is assumed that there will only be one fire per pressure zone at any one time. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-66 Fire Flow Storac7e Rent lrempn+- Fire Storage Required, Land Use Fire flow, gpm Duration, hours gallons Residential Single-family 1,500b 2b 180,000 Multi-family 3,500a 3a 630,000 Commercial 3,500a 3a 630,000 Schools 2,500 2 300,000 Hospitals 6,000b 4b 1,440,000 Industrial 3,500a 3a 630,000 a1989 North Boulder Area Water and Sewer Master Plan. binsurance Services Offices. Fire storage should be determined and provided separately for each pressure zone within the distribution system. Recommended storage requirements for the City of Boulder are presented in Table 5-32. The criterion for the fire flow storage is consistent with the 2000 TWMP. 32: Pressure Zone Fire Flow Storage (MG) 1 0.63 2 1.44 3 1.44 5.2.::.3.x. Emergency Storage The volume of water that is needed during an emergency is usually based on past experience and on the estimated amount of time expected to lapse before the emergency is corrected. Possible emergencies include earthquakes, water contamination, several simultaneous fires, unplanned electrical outages or pipeline ruptures or other unplanned events. The occurrence and magnitude of emergencies is difficult to predict; therefore, the emergency storage criterion is based on past experience and engineering judgment. The emergency situation is assumed to occur at the same time as a fire. The longest recent general power outage in Boulder occurred in 1983. Power was restored in approximately six hours. Typically, emergency storage is set as a percentage of MDD. It is recommended that emergency storage be set at 25 percent of MDD for each pressure zone. The criterion for the emergency storage is consistent with the 2000 TWMP. 5.2.5.4 Storage Adequacy Evaluation Based on the storage criteria listed above, a storage adequacy evaluation is performed for the City's storage facilities under 2035 demand conditions. The total required storage for a pressure zone is a sum total of three components. • operational storage, • fire-flow storage, and • emergency storage. The required storage is compared with the actual storage for the entire system and for each pressure zone. A summary of the required and available storage volumes are presented in Table 5-33 by pressure zone. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-67 The analysis indicates a storage deficiency of 3.7 MG in Zone 1. Zone 2 and Zone 3 have a combined storage surplus of 11.9 MG. Table 5-33 indicates that the City has a net surplus of approximately 8.2 MG storage capacity for the system. Surplus storage in Zones 2 and 3 can be used to offset the storage deficiency in Zone 1 by transferring water via pressure regulating stations. Therefore, no recommendations are made for the construction of additional storage reservoirs under 2035 demand conditions. :3: .-luation Summary - Future Dennand Conditions (20~5) Pressure Zone Demands Storage Required Storage Evaluation ADDO) PHD)3) Fire Surplus/ (MGD MDD(2) (MGD Flow(4) Operational(5) Emergency(6) Required Available Deficit(7) Description ) (MGD) ) (MG) (MG) (MG) (MG) (MG) (MG) Zone l 3.9 10.1 14.0 0.6 2.5 2.5 5.7 2.0 -3.7 Zone 2 13.0 33.7 46.6 1.4 8.4 8.4 18.3 18.9 0.6 Zone 3 4.1 10.6 14.6 1.4 2.6 2.6 6.7 18.0 11.3 TOTAL 30.7 38.9 8.2 MADD = Average Day Demand (2)MDD = Maximum Day Demand (2.6 x ADD) (3)PHD = Peak Hour Demand (3.6 x ADD) (4)Storage recommended in the City's 2000 TWMP )5)Operational storage is 25 percent of MDD (6)Emergency storage is 25 percent of MDD (7)Negative values indicate storage deficit and positive values indicate storage surplus Operation of the water distribution system is monitored at the BWTF by means of a SCADA system. This system provides for continuous monitoring of all pressure reduction valves, system pressures, storage reservoir levels, hydroelectric generation units, and pump operations. The system also provides for remote control of pressure reducing valves, bypass valves, pumps and generators such that the system operators can control the distribution of treated water within the system. As presently configured, the SCADA system does not provide for automatic operation of any of the system facilities. The SCADA system does, however, provide for the recording of detailed operating data records. The City is currently in the process of developing System Operating Principles (SOPs) to have a better defined procedure for operating the reservoirs, intra-zone connections, and overall distribution facilities. The preliminary SOP states the following: `The distribution system is operated by water treatment operators using SCADA terminals at the BWTF. In general, operation depends on the production at the two water treatment plants and the demands in various zones. Intra-zone connections are used as needed to fill and drain zones and to maintain the level of reservoirs within appropriate ranges. Production from the two plants depends on factors such as system demands and water rights/supplies. BRWTF is offline more often than BWTF for maintenance, but otherwise it is online year-round. BRWTF generally provides water to Zone 1 and BWTF generally provides water to Zones 2 and 3. When reservoirs in the watershed are low, BRWTF will often treat more water and provide water to Zones 1 and 2 so that BWTF water supplies are conserved. When the reservoirs are high, usually in the spring, and start to spill over from snowmelt, BWTF will increase production to treat all the direct flow, so Zone 1 can City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-68 get some BWTF water depending on demands. When demands in the system are high, the watershed manager will decide which plant will increase production based on water rights and supplies. Notes May 2010: In the Uvinter, goal is tank fluctuation. In the summer, goal is overall storage numbers." Completion of the Distribution System SOP will assist the City to optimize energy and treatment efforts. System operating practices also have an important effect on water quality. Storage reservoirs in the distribution system serve primarily to provide a reserve for peak demand periods. During normal off-peak periods, however, there may not be sufficient water drawn out of the reservoirs to prevent stagnation. Under these conditions, a significant portion of the reservoir volume can remain in the tank for a long enough time to lose its chlorine residual thereby increasing the risk of bacterial regrowth. Prolonged retention of treated water in the system also favors the formation of DBPs, as discussed earlier in this chapter. Failure to operate the system in such a way that stagnation conditions are minimized can have public health and regulatory compliance consequences that will become increasingly important in the future as regulations become more stringent with regard to maintaining water quality throughout the distribution system. The most important factor for reservoir detention is keeping a chlorine residual in the storage reservoir. This chlorine residual is easier to maintain in the winter, due to the slower decay curve with colder water. Mixing is also important to keep the reservoir fresh. The City has recently made improvements to the inlet and outlet piping at the Booton and Chautauqua reservoirs to improve mixing in the reservoirs. This was accomplished by separating the inlet from the outlet piping by inserting a tee in the pipe and a duckbill valve. The same improvements need to be made to the Devils Thumb reservoir and the Maxwell and Kohler reservoirs already have a separate inlet/outlet pipe, so only need the duckbill valve. The Gunbarrel tank is a smaller tank, and instead of repairing it, the City has decided to install a chlorine residual monitor in it. This will better assess the perceived issue of low chlorine residual in this area. If older water age becomes a problem in any of the tanks in the winter, it may be useful to either remove the tank from service, or simply operate them at lower levels, if feasible. Standard operating procedures exist for providing water from Zone 2 to Zone 3, but these procedures need to be tested more frequently in the event that BWTF needs to be taken offline. The ability of BRWTF to treat its maximum flow has been modeled through the computer model, but also should be tested regularly to ensure proper operation of facilities. The City has developed a number of existing distribution system maintenance programs; this subsection describes the recommendations for additional practices of distribution system maintenance. 5.2.7.1 Existing Distribution System Maintenance Programs The following are the City's existing distribution system maintenance programs, based on those reported as part of the City's 2009 Annual Report. :,.2.7 I i atv i infornlatio • yste ;&Sli%ilities Maintenance Managerree~ ~t Syste,,n Uljl.Nls The City maintains both a Geographic Information System (GIS) and a Utilities Maintenance Management System (UMMS). Both systems help to track and document maintenance in the distribution system. The Water Distribution System GIS is currently housed in an ESRI ArcGIS enterprise geodatabase. This system includes layers for water mains, valves, fire hydrants, meter pits, service laterals, fitting/nodes, corrosion protection devices, and main break locations. Updating of the water system GIS is done through an ESRI ArcMap project with a set of custom editing tools. Updates to the GIS system are promoted on a weekly schedule to a production geodatabase where they are immediately available to City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-69 other databases and mapping applications. There are no major GIS design changes planned in the near future, however as GIS technology progresses design and programming modification will be required to stay current. Anticipated future enhancements to the GIS are focused more towards data quality and accuracy. Below are some areas of GIS future development that have been identified, with cost estimates: • Locate and improve accuracy of firelines: In-house Because firelines have historically been considered private utilities they have not been consistently mapped. An in-house effort is currently underway to locate and map additional firelines and associated valves. New firelines are mapped from as-builts, existing firelines are being identified and located as part of the backflow inspection program- • Water Valve Location (GPS): $60,000 Distribution system maintenance crews have long relied on valve ties (measurements to static and easily identified above ground features) to record the location of water valve boxes. This methodology is very inefficient and has proved unreliable. Valve boxes that have been lost (overlaid by asphalt repair or otherwise not visible at the surface) are difficult and time consuming to locate. The city's water distribution mapping has also proved to be spatially inaccurate and incomplete in many circumstances. These factors have proved very time consuming and costly for distribution maintenance. Accurate and complete locations of all the valves in the water system would provide a benchmark on which the entire water distribution GIS could be made accurate. • GIS Integration with UMMS: $10,000 Currently only limited maintenance information from UMMS is available within the GIS. Further development is necessary to create a two-way process that will allow more detailed and complete maintenance information to be access from within the GIS system. 5.2 7.11.2 ~utii!±ies Nlaintenaince Summa.: ;.md Future The "Utilities Maintenance Management System" (UMMS) is an enterprise database application for recording, reporting, and analyzing City of Boulder utilities system maintenance information. The application has a "SQL Server" back end (for data storage) and "Microsoft Access" front end (for data input, analysis, and reporting). The database is used to record all the details related to the maintenance of city utilities including, but not limited to, infrastructure maintained, employee hours, equipment hours, and materials. The database has undergone continual development for more than 25 years from it's inception to improve functionality. The database has been integrated with the city's utilities GIS data. This integration is currently a one-way process that pulls GIS data into UMMS. Recently an analysis of Cartegraph, a COTS (commercial off the shelf) database application was undertaken. Cartegraph is currently used by the cities Street Maintenance work group to track their maintenance activities and for pavement analysis. This analysis was put on hold due to budgetary considerations. Current development on UMMS was also put on hold for the same reason. Below are some areas of UMMS future development that have been identified, with cost estimates: • Work Order Tools: $10,000 A work order tool has been developed for wastewater main maintenance but there are several additional repetitive tasks that could benefit from work order tools. These tools allow the supervisor to create work orders for given activities that list the infrastructure to be maintained. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-70 This significantly improves efficiency since it eliminates the need for the employee to list the infrastructure maintained- This also allows for scheduled maintenance for given infrastructure and the use of several other computer analysis tools to improve the effectiveness of the maintenance program. • Cost Reporting: $10,000 UMMS does not currently have cost reports and costs for a given work record or work activity must be calculated manually. Costs reports can significantly improve system maintenance analysis to improve efficiency. • Street Patching Database Integration: $5,000 Currently a separate database is used to track utilities cut repair costs. In an effort to improve cost reporting this database should be integrated into the UMMS database providing a direct link between the infrastructure repair activity and cut repair costs, which are often a significant percentage of the cost of the repair activity. 5.`' 7,1.3 ,tiEcdi Protection Syste_rns The City conducts an evaluation of existing cathodic protection systems on water transmission pipelines. The transmission pipelines include any pipe sizes over 16-inches in diameter. Currently, only steel pipes are being evaluated. It ensures that the existing pipes have adequate protection and to replace anodes on vulnerable pipes where necessary. Eventually it is expected that cast iron, ductile iron and reinforced concrete mains will also be evaluated. There are 70 located corrosion protection devices in the City. The corrosion control test stations are at the following locations: 1. Diagonal highway 24-inch DIP pipe 2. Diagonal highway 16-inch steel pipe 3. Zone 2 steel transmission pipe 4. CU north of the Wolff Law building An evaluation was performed by CH2MHill in April 2009 (Corrosion Mitigation Plan) to evaluate the City's cathodic protection systems and provide recommendations on ways the City can meet its goals with regard to corrosion protection for transmission pipelines. As a result of this evaluation, the City plans to take the following actions to protect its transmission pipelines from corrosion: • Rehabilitate and regularly monitor the corrosion activity and cathodic protection systems on the transmission pipelines. • Develop a program to install galvanic anodes to pipelines at locations of pipeline failures or pipeline breaks. • Develop cathodic protection standards for any new transmission pipelines. 5.-1 7.1." ".,0F1 rr< gram The City has developed an Unidirectional Flushing (UDF) program based on recommendations made from previous studies. Some of the benefits sometimes realized by UDF programs include improved water quality (primary and secondary water quality standards), improved hydraulics, and reduced maintenance of pipes, valves, and hydrants. The City's UDF design was completed by Mactec in 2007. The City implemented the UDF in 2007 and flushed 450 pipe segments, accounting for approximately 20% of the total pipes that can be effectively flushed. In July of 2008, MACTEC and Merrick & Co. completed the Unidirectional Flushing Program for the City of Boulder Treated Water Distribution System Report on Program Design for 2007. This report evaluated the effectiveness of the City's UDF program. The study found that there was a lack of tangible benefits from implementing the UDF program- The City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-71 report recommended that instead of continuing the program, the City would benefit more from replacing problematic and old pipes in the system and only occasionally flushing areas where aging, unlined pipes are causing customer dissatisfaction. MWH reviewed this study and concurs with the conclusions presented based on the data provided. In 2009 MWH Soft developed hydraulic modeling procedures in InfoWater° for UDF. If the UDF program is ever initiated again, or if localized flushing is required, the InfoWater® program provides a UDF design that can easily be implemented. The sequences created in InfoWater® may be actively manipulated to serve specific complaint areas by adding or removing pipes, manipulating valve operations, and by examining the UDF results for settling velocities in the specific sequences and their adjacent pipes. The overview maps and flush journals will serve as a `road map' for narrowing in on trouble areas that then may be provided to field crews. 5.2.7. i.5 Valve Exercising Program The City has a program to exercise the isolation valves in the system once every 3 years. Once each valve is exercised and located, it is documented in the GIS and UMMS. 5.2.7.1.6 Hydrant Flushl.nig Program The City has a program to test all of the fire hydrants once every 3 years. Once the hydrant is tested it is documented in the City's GIS and UMMS. 5..'_.7.x.7 PRV arE . ti .1, Isolatlor~'V~'sl~~e Rer t,~.~al Program A program was developed in 2004 to remove the existing zone isolation valves from the distribution system. The purpose of the project was to prevent the accidental mixing of different pressure zones. The City continues to implement recommendations proposed in the 2004 report. 5.2.7.1.8 Distribtr ion System SOP In 2009, the City started preparing a SOP to document preventative maintenance and emergency response procedures in the distribution system. The SOP will cover topics such as contamination of the distribution system, main breaks, pipe replacement, corrosion control, flushing program, backflow prevention, and others. Compilation of this SOP is still in progress. J.2.... 1-'z'v.Ir'1fC' The City continues to regularly inspect its reservoirs for issues such as corrosion, condition of the interior and exterior paint, and stability of the reservoir roof. AWWA G200 calls for comprehensive inspections every 3 to 5 years and for an external visual inspection to check for environmental damage and inspection of vents and screens every 3 months. It is also advised to increase the number of inspections as tank condition worsens. 5.2.7.1.10 Preventivrs Program Backflow prevention requires utilities to protect water service connections so that degraded water, bacteria, and chemicals cannot be pulled back into the drinking water system. The City, in compliance with CDPHE requirements, requires backflow prevention on all commercial, industrial, and multifamily properties. Backflow prevention is required on all water lines entering applicable properties, including domestic (drinking water) service lines, fire suppression system service lines (fire lines), and dedicated lawn irrigation lines. Backflow prevention assemblies are installed at the point of containment (after the meter and prior to any plumbing branches) and must be tracked. Tracking is accomplished by requiring that the customer hire a certified backflow prevention assembly tester, and that the customer or tester provide a test report annually indicating that the assembly passed. As of 2009, the backflow prevention program tracks 3,900 customer accounts. The City's recently implemented program has been very City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-72 successful. Previously the City was only 4% compliant and now they are more than 80% compliant. The backflow prevention and cross connection requirements were part of the drinking water ordinances from CDPHE. 5.2.1,? 11 Hyciropo~,r.,er The City has an on-going program of inspection and preventive maintenance at the hydro facilities to protect the investment the City has made in the hydro plants and optimize the return on that investment. Some of the tasks performed as part of the inspection and preventive maintenance program are listed below: • SOPs have been established for each hydropower plant and are continually updated. • All hydropower protection relay devices are tested annually and calibrated to minimize equipment damage. • Internal rotating bearings, electrical cabinetry, and wiring are inspected regularly to reduce safety concerns an unscheduled plant outages. In addition, discussions are currently on-going with the University of Colorado's researchers to utilize the Boulder Smart Grid transmission distribution management system for efficient energy management. 5.2.7.1.12 Water S-ysten v'ec ' ity The City continues to implement the recommendations proposed in the 2008 system-wide security and vulnerability assessment report which prioritizes security-related capital improvement projects for implementation at the City's major water assets. One recommendation is to perform some tabletop exercises to simulate response to a contaminant in the distribution system or a major component failure in the system or at the plant. 5.2.7. i.13 Voatea Quality Pal®~,itoriiig The City continues to monitor water quality via monitoring instruments installed in 2008 and 2009 at different locations on the distribution system including storage reservoirs and pump stations. The current water quality monitoring stations are located as follows: • Booton valve house • Chautauqua valve house • Iris No. 2 pump station • Cherryvale pump station • Gunbarrel vault The City's water quality monitoring program not only monitors for the state and federal requirements, but also they have monitored for EDC/PPCPs, and other contaminants. This shows the City's proactive work to ensure exceptional water quality for its residents. The City is part of the UCMR3 monitoring, and as part of this will help the USEPA determine what contaminants will be regulated in the future. In addition, the City is participating in several Water Research Foundation projects, as mentioned in Section 3 and participating in a regional effort with Northern Water and other CBT entities to share costs. The City has some areas of the collection system that could use some further analysis. These locations are within the distribution system and specifically in reservoirs and in areas of concern. Online monitoring for pH, chlorine residual, and turbidity at each reservoir would assist the City in the detection of operational issues. pH will provide an idea of the corrosivity of the water, chlorine residual provides the City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-73 age of the water, and turbidity will assist in assessing the condition of the pipes and reservoirs. Accurate level monitoring within the reservoirs would assist the City in determining how well the reservoirs are being exercised. This online monitoring should be input into the City's SCADA system to provide staff with real-time data to make operational changes to reduce water age by implementing localized flushing, or making operational changes to the system. Additional pressure and flow monitoring could also be helpful to investigate issues within the distribution system, especially near the PRVs. This information can also help to calibrate the distribution system model so that it can more accurately reflect the issues within the distribution system. One location that has been problematic is the "Heatherwood" area, which is in Zone 1, not far from the Gunbarrel reservoir. This area has been shown to have consistent problems with low chlorine residual. These problems may be a result of a stuck altitude valve that now has been fixed, but the City is in the process of installing online chlorine monitors in this area to see if the issue persists. The area has only a few pipes feeding in and out of it, and so the problem may need to be fixed by additional piping of loops in the system. More data will allow the City to pinpoint the problem and develop a good solution. This problem has not shown up in the City's distribution system model either, so getting further information and data from this area will also help to calibrate the model to the actual conditions in the area. Customer complaints can be a reflection of water quality. Boulder had 217 customer complaints in 2009, and based on the graph in the City's 2009 Annual Report, approximately 60 would be considered customer service complaints, and 157 would be considered technical quality complaints. Per 1000 service connections (assumes 29,000 service connections), Boulder has 5.4 technical service complaints per 1000 service connections and 2.1 customer service complaints per 1000 service connections. These are compared to AWWA's 2005 benchmarking results shown in Table 5-34. Table 6-34 iechnical Quality omc Connections) City of 25th Percentile Median 75th Percentile Sample Size Boulder Technical Quality Complaints Region West 5.4 2.8 7.6 14.2 59 Size 100,000-500,000 5.4 2.3 8.6 38.1 56 All Participants 5.4 2.8 7.2 17.4 165 Customer Service Complaints Region West 2.1 0.6 4.0 17.7 49 Size 100,000-500,000 2.1 0.5 4.5 50.9 49 All Participants 2.1 0.7 5.7 27.3 151 Source data from: Lafferty & Lauer, Benchmarking Performance Indicators for Water and Wastewater Facilities, AWWA, 2005. For both technical quality and customer service complaints, Boulder is in the second quartile (25 to 50th percentile, better than median) compared to utilities similar in size and location. 5.2.7.2 Recommendations for Additional Maintenance Practices MWH recommends the City implement the following maintenance practices. (Some of these may already occur, but were not documented in available data.) These are identified based on a review of standard practices identified in AWWA G200 - Distribution Systems Operation and Management. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-74 5.2.7.2.1 Valve Exercising Program It is recommended that the City continue to exercise all of the isolation valves on a regular basis (once every 3 years). Larger pipes, air release valves, air-vacuum relief valves, drain valves, and pressure relief valves should be inspected on a regular basis and the frequency may need to be increased as the pipe or valve ages. 5.2.7.2.2 Inspection and Maintena~ cd Programs Currently two City employees are dedicated to perform utility locates, which averages about 10,000 hours per year. Often utility locates take priority over doing preventative maintenance. One recommendation is that the City devote more time towards the maintenance and inspection of the distribution system, primarily PRVs, ARVs, and larger pipes. The City is just over halfway in changing out the 40 existing ARVs, and these will be completed this year. It is difficult to switch from corrective maintenance to proactive maintenance, but having complete and functional GIS and UMMS systems are critical to starting this transition. An effective preventative maintenance program will be more productive and efficient than a reactive corrective maintenance program. Having temporary staff to help with utility locates could provide more time for effective maintenance programs. 5.2 7.2.3 Fire i°',araiit Mali"t''cer%anCe and Tet'lilti i l !ratil The City recently inherited the operation and maintenance of about 2,000 fire line valves that are located in existing easements and right of ways. City staff has started locating and mapping the valves, and utilizes temporary staff (in part) during the summer to accomplish this work. In addition to this, it is recommended that the City continue to maintain and test all of the fire hydrants on a regular basis (once every 3 years). 5.2.7.2.4 Pump Station Maintenance Pump stations should undergo similar maintenance procedures as the hydropower facilities. While it is believed that the City undergoes similar maintenance procedures at its pump stations, no documentation was identified that discussed such processes. 5.2.;'.2 5 i revendon Progran', Several recommendations have been identified to improve the efficiency and overall compliance of the backflow prevention program. Several city departments currently label and track fire lines, making verification and cross-reference difficult. The City should continue to streamline fire line data so that all city departments can be assured of how many fire lines exist. Similar to fire lines, customers with access to auxiliary water such as wells and ditch water represent a potential cross-connection, and should be identified and tracked. However, there is currently no central database of all known auxiliary water users. The backflow prevention program should review options for monitoring and enforcing backflow prevention requirements on auxiliary water users and develop an approach and timetable for implementation. The City does not have a standard backflow prevention program policy for Consecutive Systems that do not currently have backflow prevention. The backflow prevention program should review its options for enforcing backflow prevention requirements on Consecutive Systems in order to develop a standard approach and timetable for implementation. The backflow prevention program should also review its options for enforcement action, given that enforcement options have not been identified outside of shutting off service. The backflow prevention program should also pursue options that would save resources spent entering data to save costs and improve efficiency. Finally, the backflow prevention program should work with the Planning Department to review and rewrite Chapter 5 of the City's Design and Construction Standards in order to bring consistency to the Standards for backflow prevention construction. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-75 The City has been using a computer model to simulate system hydraulics and operation of the water distribution since before 1980 when the first Boulder water distribution model was developed in KYPIPE_ As part of the 2000 City of Boulder TWMP, the model was improved and calibrated using field verified pressures and fire flow tests. In 2005, the City's model was integrated into the MWH Soft InfoWater® software and was upgraded to an all-pipes model. Since that time the City has been maintaining and updating the water distribution model and routinely comparing SCADA data with model results to verify the model output. The model has also been enhanced to perform 24-hour and 30-day extended period simulations (EPS) and includes rule-based logic that allows the model to operate similar to the approach taken by the operators within the City. The MWH Soft InfoWater® model used for this distribution system evaluation was most recently calibrated by the City for the IDSE Report prepared in 2006. A detailed report on the hydraulic model is provided in Appendix C for reference. This section summarizes the report. The model was used to assist in the evaluation of the distribution system under current and future conditions and to help to identify system deficiencies. Table 5-35 provides the reliability criteria that the system was measured against. ~ystern Hydraulic. Reliability G rile, Category Criteria Notes 40-80 psi Target range for normal operating pressure Pressure 150 psi Maximum target pressure (Note: Pressures at some existing areas in the system reach over 160 psi.) 20 psi Minimum allowable pressure during fire flow under a maximum day demand conditions Velocity 10 fps Maximum velocity under normal operating conditions Head Loss 10 feet/1,000 feet Maximum headloss under normal operating conditions In addition to these criteria, the distribution system was also evaluated further to understand the need for pressure zone modifications, areas of high water age, and systems operating during system failure scenarios. The first step of the hydraulic evaluation was to determine if any additional calibration would be needed for the most recent model. It was determined that none was required. The distribution system evaluation was performed by using a both steady-state and extended period simulation analysis in the calibrated hydraulic model under a variety of demand conditions. The City and MWH established a methodology for performing the hydraulic analysis which was designed to specifically meet the objectives defined by the team. The results of each evaluation are summarized below: 5.2.8.9 Hydraulic Capacity Evaluation The water distribution system was evaluated based on the reliability criteria presented in the table above. The result was that the water distribution system is able to meet Peak Hour demands without causing wide-spread violation of the reliability criteria. There are some locations within the City that show pressures less than 40 psi, however most are due to high elevation and are not the result of high headloss. The result of the evaluation was that the Boulder water distribution system does not have significant capacity issues and is able to adequately meet pressure and velocity requirements throughout the City. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-76 5.2.8.2 Fire Flow Analysis The model shows that the majority of the system is able to provide 1,500 gpm of available fire flow or greater- Only two percent of the system was estimated to provide less than 1,500 gpm_ These locations are mainly on dead end pipes or small diameter pipes. 5.2.8.3 Additional Pressure Zone Analysis The distribution system is known to have areas with high system pressure. The reliability criterion establishes a target pressure range of 40-80 psi, but areas in the system are known to have pressures that exceed 150 psi. High pressures are present along the boundary between Zones 2 and 3 and between Zones 1 and 2. In addition high pressure nodes stretch the entire north-south extents of the City. To resolve these high pressure zones, an evaluation was performed to find out if there was justification for additional sub-zones to reduce this pressure. It was determined that adding sub-zones would complicate operations and could impact the City's ability to transfer water across the system. 5.2.8.4 Water Age Analysis A water age analysis was performed using the 30-day EPS model with existing (2010) minimum month and maximum month demands to simulate water age throughout the water distribution system. Water age was used as a surrogate for water quality in this analysis. This evaluation showed that water age is greater for the minimum month simulations as compared with the maximum month scenario. Approximately 50 percent of model nodes in the minimum month scenario have water that is greater than four days old. However in the maximum month scenario, only 12 percent of the model nodes have water age that is greater than four days old. For the purpose of this analysis, it is assumed that the minimum month scenario represents a winter condition when temperatures are lower and a maximum month represents a summer time condition. Assuming that water quality is affected by temperature, it would be reasonable that higher water ages in the distribution system would be acceptable during the winter months when temperatures are colder. 5.2.8.5 System Failure Analysis Five different system failure scenarios were modeled to understand how the City of Boulder could meet demand during a variety of variety of failure conditions. The five scenarios were.- 1 . BWTF out of service with minimum day demands being met entirely from the BRWTF through pump stations 2. Sunshine pipeline out of service with maximum month demands being met from the BRWTF and BWTF through the Canyon pipeline only, in combination with the Iris, Cherryvale, Maxwell and Kohler pump stations, hydroelectric facilities, and PRVs as needed. 3. BRWTF out of service with maximum month demands being met entirely from the BWTF through the Maxwell, Kohler, Iris, and Cherryvale hydroelectric facilities and PRVs as needed. 4. Canyon pipeline out of service with maximum day demands being met from the BRWTF and the BWTF through the Sunshine Pipeline only, in combination with the Iris, Cherryvale, Maxwell, Kohler, Iris, and Cherryvale hydroelectric facilities and PRVs as needed. 5. Sunshine pipeline and BRWTF out of service with minimum day demands being met from the BWTF through the Canyon Pipeline only and the Maxwell, Kohler, Iris, and Cherryvale hydroelectric facilities and PRVs as needed. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-77 Model results from each scenario were compared against the reliability criteria to determine how well the system was able to meet demand while maintaining level of service under each scenario. For all system failure scenarios, the City's water distribution system is able to meet the demand condition without dramatically impacting level of service within the distribution system. 5.2.8.6 Pipeline Aging Although not included in the hydraulic analysis above, equally important in an evaluation of the distribution system is the age of the pipes. Over 70 percent of the pipes in the distribution system are over 30 years old. A summary of the relative pipe age is shown in Table 5-36. Table 5-36: rnary of Distribution System Piping 1950s 1960s 1970s 1980s 1990s 2000s TOTAL Total Pipes Installed 1245 1412 2205 545 886 580 6873 Total Length of Pipes (mile) 85 86 124 35 52 29 412 Percentage of Total Pipe Length 21% 21% 30% 8% 13% 7% Note 1: Table generated from information in the City of Boulder Technical Memorandum, dated 2-9-09. Note 2: The 2010 GIS Summary suggests 475 total miles of total system pipe. An analysis performed previously indicates that the average age of pipes in the City's system is over 40 years. However, it should be recognized that the inventory data base does not provide the actual year of construction for pipes installed before 1950, suggesting that the actual average age of the system is somewhat older. As the City does not have a program for replacing pipeline appurtenances such as air and vacuum release valves unless a specific problem develops, it can be assumed that these items have about the same average age as the associated pipes. While age by itself is not a reliable indicator of pipeline condition, deterioration does progress with age and ultimately any individual pipe will require replacement. Economic analyses typically use 50 years as the useful life of pipelines. This assumption takes into account that some pipes won't last 50 years, while others will last much longer, which in some cases give the impression of an indefinite life span. Pipe materials, construction standards, and installation techniques have all improved over time, implying that older pipelines could be approaching the end of their useful lives. At present the City does not have a program in place for systematically assessing the condition of pipelines or their appurtenances. As a result, with a large proportion of the system over 50 years of age there is a concern that the City could possibly be forced to replace a large amount of pipe within a short time to prevent widespread system failures. There is also some concern that system performance could be affected or pipelines damaged as a result of failures of air and vacuum relief valves, which could go undetected for extended periods due to the lack of a regular inspection and replacement program. 5.2.8.7 Pipe Materials The older pipes in the distribution system were typically cast iron or ductile iron pipe, while the newer pipes are typically PVC. Table 5-37 shows the distribution of piping across the system: City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-78 Table 5-37: Pipe Material Distribution Pipe Material Length (miles) % of Total Asbestos Cement 18 4% Cast Iron 152 34% Ductile Iron 137 30% Pre-stressed Concrete Cylinder 14 3% Polyvinyl Chloride (PVC) 107 24% Steel 16 3% Unknown 8 2% Total 452 100% Approximately four percent of the system is comprised of asbestos cement (AC) pipe. Although AC pipe does contain asbestos, its presence in the distribution system is not considered a public health threat. Testing for asbestos in the water has repeatedly resulted in asbestos concentration limits well below the limits set by USEPA and the City has been exempted from further testing by the CDPHE. The total system pipe length is 475 miles, 452 of those miles are owned and maintained by the City while 23 miles are privately owned. 5.2.8.8 Pipeline Leaks The City currently has an average of 16.1 leaks/100 miles of pipelines. Comparing this to benchmarking data, the City is much lower than average compared to others in the Western United States and those of similarly-sized cities as shown in Table 5-38. Table ;~i ison of Comparison Criteria 251h Percentile Medium 75th Percentile City of Boulder West Region 16.9 36.4 59.6 16.1 Population of 100,000 to 500,000 27.7 52.1 94.2 Source: Angela L. Lafferty and William C. Lauer, Benchmarking Performance Indicators for Water and Wastewater Utilities: Survey Data and Analyses Report, American Water Works Association, 2005. 5.2.8.9 Pipeline Breaks - Historical Studies The City's distribution system analysis has changed over the last ten years since the 2000 TWMP. Some of this information was gathered from the Pipe Replacement Technical Memorandum dated February 9, 2009 prepared by the City. The following summary is taken from this memorandum. The City of Boulder began an intense analysis of the distribution system in 2002 with Integra Engineering. A point system was developed to rate pipes based on age, material, size, soil type, and relative location in the City. The point system and methodology was integrated into the water main and main breaks databases and has been used for the prioritization of pipe replacement since 2002_ In 2007, the City created a prediction model using Integra's methodology. The model used the a statistical function called the Weibull function to correlate pipeline failure with the number of pipeline breaks. The results of this analysis produced pipe replacement costs ranging from $6 million to $10 million per year. In April 2008, the City hired HDR to critique the original Integra analysis and the Weibull function results. They improved the pipe break prediction, and they also attempted to correlate the pipe breaks to other pipe characteristics- They found a correlation when Age-Material-Soil groups were plotted with the Breaks City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-79 per Mile. They used this correlation to create a model to show which pipes should be replaced first. This model grouped pipes into similar groups and the assumption was made that the groups would fail at a similar time relative to other groups. A cut off value was chosen which was called a service level that would determine which groups of pipes should be replaced based on the number of acceptable breaks per year. The model was used to evaluate three different service levels based on the service level the City currently provides. The results of this analysis produced pipe replacement costs ranging from $4.8 million to $10.6 million per year. Unfortunately, this model was not considered to be an accurate representation of the distribution system because of the limited data available to use. One benefit of the HDR evaluation was a recommendation to evaluate pipeline breaks per unit length of pipe rather than per pipeline segment due to varying lengths of pipelines within the water system. Next the City staff began to evaluate other methods of failure prediction and pipe replacement selection. The critical break area method utilized GIS spatial mapping to locate hot spot areas where multiple breaks have occurred. An assumption was made that all pipe within the hot spot area should be a priority for replacement within the next 20 years. The results of this analysis produced pipe replacement costs at approximately $4.7 million per year. In 2008, the City looked into other correlations in Breaks vs. Operating Pipe Pressure. The City was able to finalize and run the City water distribution system model in MWH's InfoWatero program which provided additional data for analysis. Little correlation was found between system pressure and pipeline breaks, so the City continued to look at other prediction methods. In 2009, the City again reviewed its use of the Weibull function for use in predicting pipeline breaks. The City recognized that considering a single break on a pipeline does not necessarily constitute a failure in that pipeline. The current approach is to use the number of breaks in a single pipeline in evaluating when a pipeline would fail. This method is more realistic in allowing the City to select the number of pipe breaks that appeared to be reasonable in terms of cost, and is also responsible in terms of providing a stable water distribution system for its citizens. The findings of the pipe break study recommended that the threshold for the number of breaks per pipe be kept at two for CIP purposes, which allows funding of $2.1 million to be maintained during the next decade. With the aging distribution system, pipe breakage is likely to be a more common event that needs adequate money reserved. In addition, the City currently provides excellent service to its water customers and this will allow this service to continue. 5.2.8.10 Recommended Pipeline Replacement Program The previous studies summarize the significant amount of work in evaluating the pipeline leakage data and considering the sensitivity of the number of times a single pipeline breaks on the total value of the pipeline replacement program. The program has significantly reduced the number of breaks in the system. Over the last two decades the City has averaged 76 pipeline leaks in the distribution system annually. Compared to other agencies in the region, 120 annual breaks is average, and 220 annual breaks would cause the City to operate at the worst level. The results of the City's effort have been clear, over the past 5 years, the City has reduced the number of breaks to less than 40 per year. This has been accomplished by a proactive pipeline replacement program and operational (pressure-related) changes The following issues remain unresolved on the City's pipeline replacement program: • Continuation of existing practices may lead to increased number of pipeline breaks as system pipelines continue to age. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-80 • Pipeline breaks are not the only factor that would lead to pipeline replacement. Pipeline breaks are often not evident from the ground surface; unknown underground leaks could lead to significant amounts of water loss even though the breaks are not visible on the surface. • Procedures have not been developed to specifically rank and prioritize which pipelines should be replaced. For these reasons, MWH recommends a continued focus on the pipeline replacement program, replacing not only those pipelines with actual pipeline breaks, but also those pipelines with similar characteristics (material, soil type, system pressure) as those that have experienced a large of pipeline breaks- MWH also recommends refining the risk-based ranking system to prioritize the City's pipeline replacement program. A risk-based approach considers two components: the probability of failure and the consequence of failure. e._.3.A.'( babilitl 'ailure The probability of failure is a scoring system that predicts the probability of any single pipeline failing, based on predictive deterioration and failure history. While the historical number of pipeline breaks is a key component in probability of failure, other factors including age, system pressure, or pipeline breaks in similar pipelines may warrant consideration in developing scores identifying the probability of failure. Each pipeline segment would be ranked with a condition score ranging from excellent to very poor. 5.2 8.10.. :'??segUence r`f uure The consequence of failure is a scoring system that predicts the effects of a failed pipeline. Not all pipeline breaks are equal: some are catastrophic and have significant effects on the surrounding community when the break when large sinkholes appear in the roadway or lead to property destruction, either due to the sinkholes created or due to flow water. Other breaks may have a significant impact on the community's water system, lead to shutdowns of water supplies to large portions of the City or to major facilities (such as hospitals and schools). Other criteria, such as the ability to deliver fire flow, could also be included in developing the consequence of failure scores. Each pipeline segment would be ranked with a score of low impact, medium impact, or high impact. ,10.3 Cr isk Rating Combining the probability of failure and consequence of failure, a risk rating can be developed. This risk rating would guide the City in their pipeline replacement programs, as those pipelines with the highest risk rating would be replaced first as shown in Figure 5-47. Probability of Failure (Condition) Risk Ranking Excellent Good Fair Poor Very Poor Very Low Very Low Very Low Medium Low Impact Low Priority Priority Priority Priority Priority Consequence of Medium Very Low Very Low Medium Failure Impact Priority Priority Low Priority Priority High Priority Very Low Medium High Priority i High Impact Priority Low Priority Priority City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 5-81 6 Asset Management Asset management has become an important process for the City of Boulder to estimate and justify the overall renewal and replacement CIP and maintenance budgets in a strategic, defensible manner. Through a variety of recent asset management projects, including this one, the City is establishing a foundation of understanding on which it can build a more proactive asset management program to better strategically manage its water infrastructure, prioritize improvements, and maintain the value of its water asset base investment while maintaining the levels of service its customers expect. Going forward, the City may wish to take advantage of the asset management work to date on water assets with similar approaches for wastewater, stormwater, and flood management assets and tie-in an associated framework of enabling strategies, processes, data structure, and technology. These will help to coordinate and operate a successful, ongoing asset management program for the City. As a key strategy, Boulder should commit to monitoring and managing its wet infrastructure assets according to risk, and tie-in ongoing alignment of levels of service targets for reliability and risk management with the funding levels allocated for ongoing proactive asset renewal. The purpose of this approach is to dedicate more of Boulder's limited resources toward assets that present the most risk to FCU in terms of providing reliable services to its customers. By focusing on these higher risk assets, FCU should get the most value in terms of managing its risks for every dollar invested. 6.1 Previous Asset Management Studies Two previous asset management studies were performed recently, and are describe in the sections following: • Betasso Water Treatment Plant Asset Management Pilot (2009) • Iris and Cherryvale Pump Stations - Asset Management Update (2010) The Draft Betasso WTP Asset Management Pilot report completed by Carollo Engineers in 2009, consisted of an assessment of existing asset management practices and information systems used at the BWTF, recommendations of an approach and improvements for asset and data management, and implementation of a pilot for the facility sludge lagoon and drying bed facilities. The Betasso Asset Management Pilot included enhancements to each of the three primary information systems involved in managing asset data for the facility including the FastMaint CMMS, a base AutoCAD drawing, and the Asset Management Spreadsheet. In addition, it provided an implementation plan for further upgrades, including: 1. Update rehabilitation and replacement cost estimates in the Asset Management Spreadsheet 2. Complete synchronization of FastMaint and Asset Management Spreadsheet Asset IDs 3. Complete development of AutoCAD Asset Management Base Drawing City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 6-1 4. Conduct criticality evaluation and risk assessment for all assets 5. Conduct evaluation of CMMS Alternatives for asset management support 6. Implement enhancements to FastMaint (SQL Server, Web) or other CMMS 7. Formalize asset management business process documentation For further information, the reader is referred to the Draft Betasso WTP Asset Management Pilot report. In 2010, Richard P. Arber Associates conducted an asset valuation of the Iris and Cherryvale pump station facilities as part of the Water Utility Master Plan Update. In the Final Technical Memorandum, Arber presented the updated asset matrix for these facilities and its basis. 6.2 Asset Management for BRWTF and Stranded Facilities As part of this Treated Water Master Plan, MWH performed an asset management update for the BRWTF and stranded facilities. The objective of this task was to help the City better estimate the overall renewal and replacement CIP and maintenance budgets. The information was derived through workshops, desktop analysis, and field observations to evaluate, refine, and update the condition scores and replacement cost estimates of facility assets at the BRWTF and stranded facilities. The BWTF was not part of the scope of this study. The stranded facilities considered in this analysis included: • 101 Pearl and Sunshine PRV facilities • Sunshine, Orodell, Maxwell and Kohler hydroelectric facilities • Gunbarrel, Maxwell, Booton, Devil's Thumb, Kohler, and Chautauqua reservoirs Primary activities included: • Asset Data Review and Gap Filling: The City's asset data for the facilities mentioned above were reviewed and analyzed for completeness for condition-based planning purposes. Analyses of the asset base included completeness and distributions of key parameters such as asset use, size, material, age, and condition. Data gaps were addressed using City and MWH staff knowledge, as well as professional judgment. • Asset Condition Scoring: Condition scores were developed for each asset through workshops, desktop analysis, and field observation using industry best practices. • Renewal Cost Forecasting and Budget Scenario Analysis: Long term (50-year) cost forecasts were developed for the City's facility assets. The results of these long-term forecasts enable the City to determine budget levels needed for the long-term renewal and replacement of its assets. Findings highlights from this analysis include: • Data for the BRWTF were more complete than for the stranded assets. However, further review of project and facility documents helped to fill gaps. Some asset details remain to be investigated and quantified to further refine some estimates. • The condition scores for BRWTF assets were generally good. However, the condition of some dams and treated water reservoir tank roofs and piping was generally worse. City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-2 • The City may want to start planning how to address the significant cost of renewal to the BRWTF ($128M) that will be required in the 2045-2055 period, hydroelectric facilities ($10M) that occurs over 2024-2049, and reservoirs ($118M) during the mid-2050's. As part of the scope of this effort to be consistent with the Pilot, this asset management effort is built off of the output format, condition fractions, and cost factors developed during the Pilot. It took an additional step to develop a more robust analysis tool for the City utilize for consequence-based asset analysis for capital improvements planning into the future, which will serve as an important foundation for a more strategic risk based analysis down the road. The full asset management report can be found in Appendix F. A summary of the results is presented in the sections below. The BRWTF asset management results are summarized in Figures 5-48 through 5-50. As shown in Figure 6-1, average repair and renewal costs for the BRWTF are estimated at a 50-year investment need of $190M, or $3.8M per year- :V MWH I BR4VTF 50-Year Renewal Forecast Oe~ of I#uir crl 5s0,000,nn0 560 000.000 $SO,angnn0 S,mar ami $ 0,0ngnno $2u,UW.(1W Average: $3.BMper Year '.111 urjJ luU 2 Z. 11 9 11 2 ~Z 11 -1 -1 11 11 -1 11 As can be seen from the Civil, Mechanical, Electrical breakdown of the forecast in Figure 7, costs in some years are projected to exceed the annual average. These are analyzed below: 2027-2030: Approximately $24M in mechanical needs are expected in these years. This is largely due to equipment reaching its expected useful life in areas such as the DAF building, Filter Building/High Service Pump Station, Raw Water Pump Station, Administrative/Chemical Building, and miscellaneous mechanical needs across the site. City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-3 2037: Instrumentation and control renewal at the Filter Building/High Service Pump Station, general power electrical assets across the campus, and the 30" magnetic flow meter are the main contributors to this $5.8M need. 2039-2040: $10.5M is needed among these two years as the PLC-4B and instrumentation and control in the DAF Building reaches the end of their lifespan, and the High Service Pump Station in the basement of the Filter Building and the filter surface water washers in the Filter building expire. 2042: In the Administrative/Chemical Building, miscellaneous electrical assets will reach the end of their useful life, as well as the motor control center in the Filter Building/High Service Pump Station, to be the largest portions of the $5.6 investment needs for 2042. 2046: Nearly $27M of miscellaneous electrical infrastructure is expected to reach the end of its useful life across the treatment plant at Administration Building, Filter Building, Raw Water Pump Station, and throughout the campus grounds. 2047: This year, a half million dollar transformer comes due along with the high service pumps at the Filter Building at a price of $4.7M- 2060: Most of this cost is due to the 48" raw water line at the BRWTF expiring at a cost of $8M. 2051: Much of the civil infrastructure is expected to reach its useful life and require repair or replacement at most of the buildings on the site and across the site grounds. Additionally, the pipes onsite reach the end of their useful lives. The combination of these infrastructure components reaching their useful lives results in a price tag of $75M. 2055: The 42" raw water DIP extension, carbonic acid feed system, the 30" wastewater line at the filter building, and a variety of piping across the campus are set to expire at a cost of about $9M. Figure 6-2: BRV RRWTF Renewal Forecast By Discipline MWVH 5kll,lkII1,0[Nl 570,000.000 560,000.000 - 590400.01X:1 - 540,aoo.000 ■ Mechanical ■ Cron $30,090.000 S~o,kn),ucrc) E 03 3; S• O V u D G ry d E b G O G G chi G D G G City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-4 Figure 6-3 shows the breakdown of costs by facility/process. Big ticket items for the General Site Work category across the BRWTF campus that will require renewal for the next 50 years include significant portions of its mechanical, electrical, and civil components. In the Filter Building, most of the $57M includes replacement and renewal of the majority of its components as they become due. MWH BRWTF Renewal Forecast By Facility s~a:aagaa~ an nnn non ssa.aao,ooo cao.oon,oao a.]II,INNI,[N70 a Elmncal ■ MPManitll ■ Civil do❑ r.uKKI 51904J,U70 <aew {arc s Y\ ;as p r r~~~ P a ~1 'Q ~tr d' Sti t'L J~~ n,rt q} ~,4 'D c~ fiV 4' tae .~3~ oaf P0` Du ~.o G~,a elf c N E ~ wady ¢s 1,a d In addition to the BRWTF, stranded facilities including PRV, hydroelectric, and storage facilities were analyzed. 6.2.2.1 Asset Management for Hydroelectric and PRV Facilities With the City, it was decided that the analysis of these facilities would consider the facility and its assets at a higher level only and not drill down to a civil/mechanical/electrical analysis because the systems are generally less complex than a water treatment facility. These estimates total to about $11 M over 50 years, or a $200,000 average annual expenditure. The results of the hydroelectric and PRV analysis is presented in Figures 6-4 through 6-6- City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-5 Figure 6-4: Hydroelectric and PRV Facilities 50-Year Renewal Forecast Hydro & PRV 50-Year Renewal Forecast Q) MWH 30SINESS SOLUTIONS C[ly of 9w.dv y1,(ILNI [NKI S S. SINI,IKKI X3.009.000 SI, SLX I,IXKI S1,UW,WU til. S W.UiIU 51,009,0ElCI Average: S01M per year $SIN),IKKI T Projected costs well above the annual average occur in the following years as analyzed below. 2024: About two-thirds of these costs amounting to $1.3M is attributable to the turbine bypass valve at the Orodell facility. The turbine bypass valve at Kohler and the turbine/generator at Maxwell are significant costs as well at approximately $200,000 each. The difference in cost between the Orodell valve and the Kohler valve are that the Orodell valve has been rated as a "complex" project by the City, which is defined as needing help of a significant level external to the City to complete the project, thus adding additional cost. 2027: An investment need of $350,000 is identified for this year to renew Kohler's turbine/generator. 2029: Over half of the $600,000 slated for this year would be to renew Orodell's turbine/generator. 2030: The replacement cost of Sunshine's turbine generator amounts to $3.3M. Sunshine's turbine/generator is Boulder's most expensive one and would be a "complex" project. 2043: Structural work at Sunshine will amount to $300k and includes its retaining walls. 2045: The altitude valves for the reservoir tank at Maxwell and the PRV valves at the 101 Pearl PRV Station will amount to $2.5M this year. 2049: The costs of approximately $1.4M are attributable to the expiration of the Sunshine PRV vault. City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-6 Figure 6-5: Hydroelectric and PRV Facilities Renewal Forecast by Facility Hydro& PRV Renewal Forecast By Facility a MwH ($300k/yr. Avg.) .,E sf Bro.= 54,SW,f1l10 + S-0 UW,OW 53 100,000 $.i,llllfl,[NHl $~,S1141,[NHl 52.000,000 51 500,000 SLUW,WP $Mm 5- b s#' ti i h S,~ 4yQe° 1 As shown in Figure 6-5, average repair and renewal costs for hydroelectric and PRV facilities are largely due to extensive repair or replacement needs throughout the Maxwell, Orodell, and Sunshine hydroelectric facilities. 6.2.2.2 Asset Management for Storage Facilities With the City, it was decided that the analysis of these facilities would consider the facility and its assets at a higher level only and not drill down to a civil/mechanical/electrical analysis because the systems are generally less complex than a water treatment facility. As shown in the figures in this section, average repair and replacement costs for treated water storage facilities are estimated at $3.6M per year, or about $180M over 50 years. Figure 6-6 shows spikes well above the annual average in the years discussed below: 2016: The $8.9M renewal needs in 2016 mainly represent the roof structure at the Kohler reservoir. Kohler has a corrugated metal roof supported on a system of concrete, steel beams, and concrete columns. 2046: Electrical and coating needs at Gunbarrel reservoir, electrical work at Booton reservoir, and sitework and electrical needs at Devil's Thumb reservoir comprise the $10M of improvements forecasted for 2046. 2047: Sitework, including yardpiping and related valves and vaults, is expected to expire at the Maxwell reservoir at a cost of $12M. 2054: Replacement of the concrete tank at Maxwell reservoir represents a 2054 cost projected at $79M and $3M for electrical work at Chautauqua. The current condition rating of the tank is a "4," representing that at least 40% renewal of the tank is required presently. Maxwell's tank will need to be evaluated as to whether repair will serve as a suitable substitute for full replacement, especially in the area of the tank that is pushing out away from the rest of the tank. The City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-7 evaluation required should be a complete structural evaluation and include evaluation of the structural components of the tank that can only be viewed from the inside where presently unviewable damage may or may not be present. If the structural evaluation pushes the condition rating to a "5," representing 90% renewal required, the tank will need to be repaired or replaced much sooner, likely the year of 2017 at a cost around $26.5M. Depending on the evaluated structural condition, repairs may potentially be possible to extend the life 15 to 20 years from the time of repair if it makes sense to buy time for other assets to be addressed instead of Maxwell's tank during this time. If the tank can be pulled offline for awhile, repairing the concrete lining on the bottom may be of great help to prevent seepage and also prolong the life of the tank. 2056: Maxwell reservoir is projected to need approximately $9.1M of miscellaneous mechanical renewal in 2056. 2057: Booton reservoir's concrete tank and concrete valve vault are set to expire in 2057 at an estimated cost of $22M. Sitework at Kohler, which includes yardpiping and related vaults, is also expected to cost about $4.5M. Water Storage 50-Year Renewal Forecast © MWH BUSINESS SOLUTIONS 570.000.000 City of Bolder $80,000,000 $70,000,000 $60,000,000 $50,000,000 - 540.000,000 $30,000,000 $20,000,000 Average: $3.6M per year $10,000,000 0 0 0 0 0 0 0 0 0 0 °0 0 0 0 0 The storage tank costs are largely attributed to Maxwell reservoir's renewal needs throughout the facility, including repair or replacement of its tank and its sitework, partially which may be required to stabilize the integrity of the tank. The significance of the costs of renewal at the Maxwell facility compared to the other facilities is shown in Figure 6-7. The majority of the costs at Booton are attributable to renewal of its tank. City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-8 Figure 6-7: Water Storaqe Renewal Forecast by Facility 50-Year Water Storage Renewal Forecast By Facility © mwH `s 11T1CNb ;70,c00,000 560,000,000 $50,000.000 $40,000,000 530,000.000 520,000,000 $ 10,000.WO 5- .111P odo. od C` ~2 t i t~ e 5~ < el6 a~a Ci c~a`t °~aF~~`P Qo ocP ~ ~cJ~ E ~r` ~~J O~ :.2.. Overall Asset Management 'he BRWT , S Stt.,~ . ded 7_fis;t; Based on the analysis performed, approximately $7.6M per year should be budgeted to ensure the sustainable repair and renewal of the BRWTF and stranded facilities to attain the 50-year needs of $381M. With this project, the City has taken important first steps in enhancing its approach to asset management for the BRWTF and stranded facilities. Several of these achievements pertaining to these facilities are listed below. • Gap filling and reconciliation of asset data • Assigning initial condition scores to determine the probability of failure - an important first step to being able to develop risk scores • Developing long term (50-year) renewal forecasts • Constructing asset management workbooks for three facility categories Potential near-term enhancements to the City's existing asset management approach to consider include: • Migrating asset data into one database driven application for more robust asset management capabilities. • Establishing a data framework to have a clear and consistent asset hierarchy and asset registry. • Incorporating the consequence of failure analysis to enhance the condition-based analysis of this task to strive for an enhanced asset renewal forecast that is risk-based. • Establish a process to enable and support ongoing and regular updating of data, scores, and overall asset management strategy. City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-9 This proactive and comprehensive understanding of the City's condition profile will allow the City to address its current and expected future asset needs through careful planning and management of its inspection, maintenance, and asset repair and replacement activities. 6.3 Summary of Boulder's Overall Asset Management Strategy Asset management has become an important process for the City of Boulder to estimate and justify the overall renewal and replacement CIP and maintenance budgets in a strategic, defensible manner. Through a variety of recent asset management projects, including this one, the City is establishing a foundation of understanding on which it can build a more proactive asset management program to better strategically manage its water infrastructure, prioritize improvements, and maintain the value of its water asset base investment while maintaining the levels of service its customers expect. Going forward, the City may wish to take advantage of the asset management work to date on water assets with similar approaches for wastewater, stormwater, and flood management assets and tie-in an associated framework of enabling strategies, processes, data structure, and technology. These will help to coordinate and operate a successful, ongoing asset management program for the City. As a key strategy, Boulder should commit to monitoring and managing its wet infrastructure assets according to risk, and tie-in ongoing alignment of levels of service targets for reliability and risk management with the funding levels allocated for ongoing proactive asset renewal. The purpose of this approach is to dedicate more of Boulder's limited resources toward assets that present the most risk to Boulder in terms of providing reliable services to its customers. By focusing on these higher risk assets, the City should get the most value in terms of managing its risks for every dollar invested. Additional recommendations for asset management at the City include: 1. Efficiently assess its asset management capabilities against industry best practices across strategy, people, processes, data, tools, and performance to identify "quick win" improvements to attain stakeholder buy-in and chart a roadmap to improvement across these areas. 2. Develop an ongoing, programmatic approach to asset management to drive more proactive asset strategy throughout the organization in a coordinated manner and realize benefits associated with more defensible renewal budgets and utility performance. A quality asset management program will have both planning and implementation components, build on existing efforts, staff knowledge, and tools, and reach across water, wastewater, stormwater and flood management vertical (i.e, facilities) and horizontal (i.e., pipes) assets. 3. Create an overarching vision and guiding policies and a plan to communicate them to attain staff buy-in, understanding, and coordinated and useful contributions to better asset management. 4. Identify the targeted levels of service to customers that the City idealizes through enhanced asset management and associated performance metrics to help steer priorities and decisions related to the ongoing maintenance, repair, and replacement of assets. 5. Structure a data framework to have a clear and consistent asset hierarchy and asset register, communicable throughout the organization, that can be used to consistently structure and organize asset data, as well as enable better data version control, completeness, utilization, and integration in and between software platforms including UMMS, GIS, and CAD_ City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-10 6. Apply a highly defensible and transparent, proactive risk based approach to renewal forecasting across vertical and horizontal assets to consider the criticality of assets in addition to just their condition for repair or replacement across all asset groups. The risk based approach could be similar, but more proactive than the one currently utilized for reactive maintenance of pipelines. 7. Analyze the City's key enterprise IT systems, including those for the UMMS, financial management, CIS, GIS, document management system and other key technology as well as their current use, performance, and objectives. Weigh Commercial Off-the-Shelf options with needs and against the City's present enterprise systems to determine the best tools, processes, and integration to meet the needs and visions of the City across its asset base and consider an overall asset management platform tool and dashboard. 8. Establish business processes to enable and support ongoing enhanced asset management, regular updating of condition/risk scores, and an overall asset management strategy. 9. Roll-in climate adaptation planning and vulnerability assessment of source water asset and others into risk based asset management planning. City of Boulder Draft Treated Water Master Plan (December 2010) Page 6-11 7 TWMP Recommendations and Conclusions 7.1 Treatment Facilities The following are recommendations related to mid to high priority items taken from the CIP list. Due to the "visionary" nature of the lower priority items contained in the CIP list, no discussion or recommendations are provided for these items as they are not expected to reach a sufficient priority level to warrant discussion prior to the next master plan update. The evaluations of the water quality and plant operating data yielded the following conclusions which form the basis of the recommendations provided in the subsequent section. • In general, a UFRV that is less than 5,000 gal/ft2 is unacceptable because of the extremely short filter run lengths. A low UFRV could indicate inadequate pretreatment, excessive or fine mudballs in the filter media, mineral precipitates in the underdrains, air binding, or hydraulic restrictions causing inadequate head between the filters and the clearwells. A UFRV that is over 10,000 gal/ft2 is indicative of normal filter performance. • To go beyond the current sustainable plant flow, the UFRV of Filters 1 through 4 and for the period of high color needs to be increased. • The reported pretreatment problems at the plant flow of 30 to 35 mgd did not show up in the data analysis and investigation. This is thought to be primarily due to the fact that there is not a whole lot of plant performance data to review at these flows. • The operations staff has done well to manage the operation of the plant during challenge conditions, to produce high quality treated water, and to shift the treated water production to the BRWTF when the existing capabilities of the BWTF are reached. • The lagoons are at their capacity for storing the dilute sludge from the sedimentation basins. A thickening process would help to reduce the sludge volume significantly. • Filters 1 through 4 were constructed at a different time than filters 5 through 8 and as a result they may have different underdrain systems, which could account for some of the differences in UFRV between the filters. In addition, some of the fines may have been removed in filters 1 through 4 during the episodes of air entrainment, which now have been resolved. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-1 • Filters 1 through 4 have been in operation longer than what Filters 5 through 8 have been. Being in operation for a longer period of time provides more of an opportunity for the underdrains to become clogged with mineral deposits. • Improvements in the pumped-diffusion mixing of coagulants will improve the downstream flocculation, sedimentation and filtration processes. • Improving the filterability of the floc formed through the treatment for color removal will have a marked improvement on the overall treated water production as color has to be removed from the source water about 25% of the time. • The City has determined that they do not plan on closing any of the waste impoundments at the BWTF or the BRWTF. Testing of the residuals for constituents of concern has been ongoing. The following recommendations are made based on these conclusions: 7.1.9.1 Studies 1. Perform a series of bench-, pilot-, and plant scale tests to evaluate plant performance at flows near the desired capacity of 46 MGD. The test should be performed during the spring runoff when the concentration of color is at peak values. Consideration should be given to evaluating flocculation and filtration aids and alternative strategies for improving the filterability of the floc. The plant-scale test will provide an opportunity to further investigate the reported pretreatment problems at flows in excess of 30-35 MGD and to verify the maximum filter hydraulic loading rate. 2. Perform an inspection of the filter underdrains in Filter Nos. 1 and 5 to check for clogged passages. 3. Perform a grain-size distribution and sieve analysis of the media in Filter Nos. 1 and 5 to determine and compare characteristics of the media. 4. To determine the accuracy of the flow measurement at BWTF it is advisable to hire a consultant who specializes in this type of flow measurement to perform a thorough review of all measurement devices, their installation and signal conversion from meter readings to flow output on the control panel. This study would confirm whether the flow meters are properly installed and calibrated, and whether any modifications are required. It is also advisable to investigate potential locations and flow measurement technologies for combined influent flow measurement at the head of the plant- This flow measurement should take place upstream of any side-stream processes. Accurate combined influent flow measurement is essential to be able to confirm upstream flow measurement and losses through the treatment process. Accurate treated water flow measurement is equally important to determine the treated water capacity of the plants and also to ensure efficiency throughout the system. 5. Pilot studies should be performed on thickening options for the residuals from the sedimentation basins. 6. Develop viable workforce strategy that includes appropriate succession planning and knowledge transfer. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-2 7.1.1.2 Capital Improvements 1. Improve performance of the pumped-diffusion mixer by adding either a VFD on pump or a flow control valve and providing an additional coagulant feed point in the pump header immediately upstream of the spray nozzle. 2. Improve the residuals thickening, dewatering, and drying process by constructing two new gravity thickeners to thicken the suspended solids coming from the sedimentation basins and installing a centrifuge-type dewatering facility to treat the float from the DAF and gravity thickeners. This may be best accomplished through two projects: thickening and dewatering. 3. Pending the results of the plant-scale testing and the recommended plant capacity evaluation, decide whether to: 1) install flocculation/sedimentation basin baffling and equipment rehabilitation, or to 2) retrofit new flocculation facilities and lamella plate sedimentation system in existing basins. 4. Rehabilitate filter gallery including valve and actuator replacement and repainting of gallery piping. 5. Increase lime feed capacity. 6. Add more standby generator capacity. The current capacity is maximized. 7. Tie chemical feed control to SCADA. 8. Upgrade chemical storage facilities. 9. Add laser turbidimeters. 10. Add residual aluminum analyzer 11. Upgrade on-line instrumentation and SCADA reports. Evaluation of the BRWTF indicated that the plant is expected to be capable of consistently meeting known and foreseeable water quality requirements at a flow rate of 20 MGD. A number of improvements are needed, however, to enhance operability and reliability and to provide effective multiple-barrier protection and consistently high finished water quality. 7.1.2.1 Raw Water Delivery The raw water intake at the BFC is reported to be unsafe. The corroded and poorly constructed access way and platform is in need of replacement. Additionally, the cleaning of the screen is currently done manually. Safety concerns and operator interaction with this intake can be minimized with the installation of an automated self-cleaning screen. When performing these upgrades, the City should also ensure that power and communication lines be routed to this location to allow for lighting and communication at this location. 7.1.2.2 Filtration Although currently rated as low priority capital improvements, it is important to note that filter to waste capability and backwash pretreatment were recommended in the 2000 Treated Water Master Plan due to concerns related to future regulatory requirements. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-3 A detailed evaluation of the existing filters should be conducted to determine the extent to which rehabilitation is required, particularly with regard to the underdrains and other components which can't be easily seen. As part of this study, the 2000 recommendation for adding filter to waste capability and backwash pretreatment should be revisited. The filters are currently in need of rehabilitation including the replacement and updating of internals, media, valves, actuators, filter control consoles, and instrumentation. The concrete walls are also in need of being recoated. 7.1.2.3 Finished Water Pumping A study should be conducted to accurately define the problems with the high service pumps, explore alternative pump styles and/or configurations, and perform a net present worth analysis to determine if the cost associated with the installation of VFD's can be justified. 7.1.2.4 Chemical Systems Automation of chemical systems has been identified as an operability issue that has the potential to improve treatment process performance and make more efficient use of chemicals. Chemical feed systems would be controlled to automatically respond to changes in plant flow and critical process parameters. Feed rates would be adjusted in small increments at frequent intervals so that the dosage at any given time will match the required dosage more closely than is possible with the current manual feed adjustment system. Automating the chemical feed systems would involve modifying or replacing any existing chemical feeders and metering pumps not capable of responding to control signals from a remote location. The plant SCADA system could be reprogrammed by City staff to provide the automatic control for the chemical systems. Additional instrumentation for flow and other process parameters would be needed to send signals to the SCADA system for analysis and conversion to control signals to the chemical feed systems. 7.1.2.5 Waste Impoundments If there are waste impoundments that the City plans to decommission in the near future, preparation of a closure plan and certification for the impoundments should occur before promulgation of the Section 9 Waste Impoundment Regulation. A closure plan and certification for an impoundment will remove the impoundment from the regulation. The City has determined that they do not plan on closing any of the waste impoundments at the BWTF or the BRWTF, as such, the old lagoons at BRWTF may need to be lined to bring them in compliance with the regulations. Testing of the residuals for constituents of concern has been ongoing. The new lagoons should be evaluated to determine the structural integrity of basins and to determine if site drainage issues exist. The results of this study should include recommended improvements and suggest a timeline for inclusion in either the capital improvements or operations and maintenance budget. 7.1.2.6 Process Instrumentation and Control As previously noted, one of the most significant problems associated with operating the BRWTF is the difficulty in providing operating staff 24 hours a day during the peak use months while providing no operating staff during the off peak months. One option would be to provide the necessary instrumentation and controls to allow the plant to operate unmanned during the evening and overnight with remote monitoring and control from BWTF via the SCADA system. This would require the automation of the chemical feed systems, which would involve modifying or replacing any existing chemical feeders and metering pumps not capable of responding to control signals from a remote location. The SCADA system would be reprogrammed to provide the automatic control for the chemical systems. Additional instrumentation for flow and other process parameters would be needed to send signals to the SCADA system for analysis and conversion to control signals to the chemical feed systems and to trigger alarms City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-4 for critical equipment failures or indicators of unacceptable process performance. Provisions for remotely shutting down the plant would also be provided for emergency situations such as failure of the disinfection system. Plant site security and monitoring would also need to be improved to prevent unauthorized entry and ensure safe operations during unmanned hours. In addition to providing adequate alarm systems and possibly surveillance cameras, the site would need to be closed during unmanned hours, which would impact users from other departments and agencies that use facilities at the site. The 2009 cost estimate for this work is $4.3 Million. As regulatory requirements become increasingly stringent, accuracy and sensitivity in measurements for process monitoring and control becomes increasingly important. To maintain the necessary level of confidence and control necessary for optimal performance, on line instrumentation will need to be upgraded as new and better equipment is developed. Instrumentation improvements would include installation of laser turbidimeters on individual filter effluent lines to supplement the existing turbidimeters. A total organic carbon (TOC) analyzer and an improved alkalinity analyzer would enhance process monitoring and control. Other instruments identified by plant staff as useful are an in line manganese analyzer for Boulder Reservoir and a UV spectrophotometer. The City currently has on-line turbidity monitoring on BFC water. However, the City may benefit from monitoring other water quality parameters such as TOC and/or ORP at this location in order to help the operators anticipate poor raw water quality events on the BFC water. 7.1.2.7 Miscellaneous The City should monitor the effect of the new carbonic acid feed system as it relates to enhanced TOC removal. It is important to determine if further TOC removal enhancement such as preoxidation with chlorine dioxide will be necessary to meet lower DBP limits if this becomes the case at some point in the future. Taste and odor concerns related to the presence of bluegreens in Boulder Reservoir should continue to be monitored by the City and these events should be recorded including any complaints that are received which could be related. Depending on the frequency and severity of such events, the City may wish to initiate a study to determine preventative and/or treatment options to mitigate the issues related to the presence of bluegreens. The options investigated in this study may include the following: • The addition of Powder Activated Carbon (PAC) which may prove sufficient if the taste and odor issues are mild. • The use of Granular Activated Carbon (GAC) which has been shown to be reasonably effective. • The use of Ozone which is a strong oxidant and can be used to control more severe taste and odor events. • The implementation of reservoir management techniques which could reduce the formation of bluegreens in the source water. A study should be conducted to evaluate and recommend alternatives for redundant or back up power to the facility. Two alternatives include the installation of a second power feed from a different utility substation, or the installation of engine driven generators with sufficient capacity to run the BRWTF at full capacity. The results of this study should recommend a preferred alternative and suggest a timeline for inclusion in the capital improvements budget. With the ever present possibility of requiring BRWTF to run at full capacity due to unexpected shutdowns at BWTF, the City should consider creating standard operating procedures for use during such events. Further to the standard operating procedures, the City should also consider implementing a regular City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-5 schedule in which to test the functionality of the treatment plant and distribution system components under various outage conditions. Such regularly scheduled tests would aid the City's staff in determining weak points, refining procedures to allow for smooth transitions, and increasing the general preparedness for the unexpected. Particular items of concern include but are not limited to: • Ensuring treatment plant influent lines are kept relatively clean so that the scouring of sediment will not impact the ability of the plant to treat at full flow • Ensuring that the plant's chemical systems and general treatment capability are up to par and ready to treat the full 20 MGD • Verifying that the distribution system is capable of handling 20 MGD sourced from the BRWTF • Verifying that water can be lifted to Zone 3 in sufficient quantity • Miscellaneous security improvements defined by the Vulnerability Assessment should be reviewed and implemented as necessary. • Develop viable workforce strategy than includes appropriate succession planning and knowledge transfer. • Improve chemical mixing at the filter effluent post flume. 7.2 Distribution System Recommendations Based on the discussion of the various distribution system components, the following recommendations are made in Section 5. Below are some areas of GIS future development that have been identified, with cost estimates. Further explanation is provided in Section 5: • Water Valve Location (GPS): $130,000 • GIS Integration with UMMS: $10,000 Below are some areas of UMMS future development that have been identified, with cost estimates. Further explanation is provided in Section 5: • Work Order Tools: $10,000 • Cost Reporting: $10,000 • Street Patching Database Integration: $5,000 The following recommendations are made for the hydroelectric generating facilities: • The CMU Crack at the Maxwell Hydroelectric Station building should be inspected further to determine the cause and a repair procedure should be developed and implemented prior to further deterioration. • Sunshine Hydroelectric Station has some minor damage to the stacked rock retaining wall around the perimeter. Additionally, based on discussions with field crews, a flow meter to the Sunshine hydro facility 30-inch diameter pipeline is recommended. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-6 • The Orodell Hydroelectric Station needs a new actuator for the 12-inch bypass downstream isolation butterfly valve and a new battery backup for instrumentation and control. The following recommendation is made to the PRV stations: • The 101 Pearl Street PRV has the potential for a grading improvement and a gravel or concrete pad for the parking/turn area. • Based on discussions with field crews, a rehabilitation or replacement of the control system at the Sunshine PRV is recommended. Based on interviews with operations staff, the following storage reservoir recommendations are made: • Replace differential pressure sensors at Chautauqua Reservoir and Devil's Thumb Reservoir with level sensors- Improvements to allow for greater treated water reservoir mixing have occurred on Chautauqua, Kohler, Booton and Maxwell, and are planned for the others. • Install new, redundant level sensors in all of the treated water reservoirs. • The results of the 2010 CDPHE Sanitary Survey will require minor improvements to the reservoirs, including the installation of mesh screens on all openings on the reservoirs, and extensions on a couple of overflow pipes to ensure erosion does not occur. Additionally, the following recommendations are made for the storage reservoirs from the structural evaluation. The following recommendations are made for Maxwell Reservoir: • Longitudinal crack close to the Southeast corner of the reservoir should be inspected further for the potential causes of the crack and a repair procedure should be developed before the winter season. • Eroded soil areas along the perimeter of the reservoir should be inspected further for the cause of the erosion and a repair procedure should be implemented. Suggest replacing the grass/soil adjacent to the structure with free draining gravel to help with erosion. • Construction and movement joints at the corners and at the midpoint of the North and South walls of the reservoir should be sealed from external weather before the winter season. • The layout surrounding the reservoir ground access area should be investigated and a re-grading solution should be developed and implemented. The steel enclosure should be re-coated and the joints re-sealed. • The roof at a minimum should be recoated or a new roof system should be developed to minimize trapping moisture against the concrete double tees. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-7 • All coated surfaces should be analyzed to determine the current condition is adequate to prevent corrosion for external elements. Form the current visual inspection, there are many areas that need to be re-coated. • Further investigation of the internal concrete floor and composite asphalt lining should be conducted to determine the condition and remaining service life. The leaking joints can lead to problems along the perimeter of the structure including settlement issues and possible contamination of the reservoir- The following recommendations are made for Kohler Reservoir: • The roof coating system has failed and should be repaired or the entire roof should be replaced. Further investigation is needed to determine the condition of the metal decking as well as the roof steel support framing members. It might be necessary to replace the entire roof system. • Joints in the concrete walls that have opened up due to wall movements should be sealed and protected from external weather. This is necessary to prevent future erosion problems. • Coating system on the gutter between roofs has failed and the condition of the gutter should be evaluated to determine if it should be replaced or re-coated. • Further investigation of the internal concrete floor and composite asphalt lining should be conducted to determine the condition and remaining service life. The leaking joints can lead to problems along the perimeter of the structure including settlement issues and possible contamination of the reservoir. The following recommendations are made for Devil's Thumb Reservoir: • Rock pits surrounding the tank should be cleaned and re-coated on an annual basis. • Finished Grade around the back side of the tank should be re-graded to allow proper drainage of the site. • Rocks need to be removed from the roof. • Further investigation into why the tank roof is dented and deformed is needed to identify if the possibility of the roof collapsing or failing in the near future exists. • Concrete foundation needs to be protected or repaired. • Vegetation next to the tank needs to be removed. • Rain guard might need to be installed facing the opposite direction, further investigation is needed. • Internal coating needs to be removed and re-coated because it contains lead. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-8 The following recommendations are made for Chautauqua Reservoir: • Perimeter wall shrinkage cracks should be "V" grooved and sealed to prevent future erosion. • Built up roof system has failed and needs replacing. Suggest considering a separate roof system that isolates the roof from the concrete double tees. • Roof vents need to be re-coated. • Further investigation of the internal concrete floor and composite asphalt lining should be conducted to determine the condition and remaining service life. The leaking joints can lead to problems along the perimeter of the structure including settlement issues and possible contamination of the reservoir- • Further investigation of the double tee shear tabs is needed to determine if the roof can perform as originally designed. New tabs might be needed, or the entire roof might need to be replaced. The following recommendations are made for Booton Reservoir: • Rock pits should be cleaned and re-coated on an annual basis. • Vegetation should be kept from growing over the slab-on-grade and ultimately the adjacent soil should be removed and replaced with weed barrier and free draining rock. • The bird nests and excrement should be removed from behind the soffit and along the tank. After cleaning the area, bird screens or wire mesh should be installed between the soffit and the roof overhang to keep birds from nesting behind the soffit. • Investigate the purpose of the external box that might contain a corrosion protection device. The following recommendations are made for the distribution system: • Continue the ongoing pipeline replacement program. A risk-based prioritization for the replacement program is recommended. • Install online monitoring of chlorine residual, turbidity, and pH in key points in the distribution system, including at reservoirs and problematic areas. Connecting these online samplers to the SCADA system will allow staff to determine where problems exist and identify areas where localized flushing needs to occur or operational adjustments need to be made. • Additional pressure and flow metering throughout the system is also recommended to confirm operational strategies and model accuracy. C-factor modeling is also recommended to determine the roughness in key pipes in the distribution system. Additionally, based on operator interviews, additional water quality sampling stations are recommended throughout the distribution system. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-9 The following additional studies are recommended for the distribution system. • There are some locations with pressures from the hydraulic model below 40 psi. Each of these should be investigated further to evaluate whether improvements need to be made to address these deficiencies. • There are some locations with fire flow capacities from the hydraulic model below 1500 gpm. Each of these should be investigated further to evaluate whether improvements need to be made to address these deficiencies. • Develop a risk-based approach to the pipeline replacement program to prioritize facility replacement. • Staffing needs need to be evaluated and methods for knowledge retention developed with much of the workforce retiring over the next several years. 7.3 Asset Management Recommendations Based on the analysis performed by MWH for the BRWTF and "stranded facilities," and Carollo for the BWTF, approximately $9.OM per year should be budgeted to ensure the sustainable repair and renewal to attain the 50-year needs of the BRWTF, BWTF, and "stranded facilities" totaling $452M. With this project and the Carollo asset management project, the City has taken important first steps in enhancing its approach to asset management for its facilities. Near-term recommendations for the City's existing asset management approach include: • Migrating asset data into one database driven application for more robust asset management capabilities. • Establishing a data framework to have a clear and consistent asset hierarchy and asset registry. • Incorporating the consequence of failure analysis to enhance the condition-based analysis of this task to strive for an enhanced asset renewal forecast that is risk-based. • Establish a process to enable and support ongoing and regular updating of data, scores, and overall asset management strategy. Longer term recommendations for the City's asset management strategy include: 1. Efficiently assess its asset management capabilities against industry best practices across strategy, people, processes, data, tools, and performance to identify "quick win" improvements to attain stakeholder buy-in and chart a roadmap to improvement across these areas. 2. Develop an ongoing, programmatic approach to asset management to drive more proactive asset strategy throughout the organization in a coordinated manner and realize benefits associated with more defensible renewal budgets and utility performance. A quality asset management program will have both planning and implementation components, build on existing efforts, staff knowledge, and tools, and reach across water, wastewater, stormwater and flood management vertical (i.e, facilities) and horizontal (i.e., pipes) assets. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-10 3. Create an overarching vision and guiding policies and a plan to communicate them to attain staff buy-in, understanding, and coordinated and useful contributions to better asset management. 4. Identify the targeted levels of service to customers that the City idealizes through enhanced asset management and associated performance metrics to help steer priorities and decisions related to the ongoing maintenance, repair, and replacement of assets. 5. Structure a data framework to have a clear and consistent asset hierarchy and asset register, communicable throughout the organization, that can be used to consistently structure and organize asset data, as well as enable better data version control, completeness, utilization, and integration in and between software platforms including UMMS, GIS, and CAD. 6. Apply a highly defensible and transparent, proactive risk based approach to renewal forecasting across vertical and horizontal assets to consider the criticality of assets in addition to just their condition for repair or replacement across all asset groups. The risk based approach could be similar, but more proactive than the one currently utilized for reactive maintenance of pipelines. 7. Analyze the City's key enterprise IT systems, including those for the UMMS, financial management, CIS, GIS, document management system and other key technology as well as their current use, performance, and objectives. Weigh Commercial Off-the-Shelf options with needs and against the City's present enterprise systems to determine the best tools, processes, and integration to meet the needs and visions of the City across its asset base and consider an overall asset management platform tool and dashboard. 8. Establish business processes to enable and support ongoing enhanced asset management, regular updating of condition/risk scores, and an overall asset management strategy. 9. Roll-in climate adaptation planning and vulnerability assessment of source water asset and others into risk based asset management planning. 7.4 Treated Water Improvement Project Recommendations The purpose of this TWMP is to establish a record of the condition and needs of the City's treated water system for the next 20-year planning period. As part of this effort, a list of needed improvement projects was developed through discussions with City staff and recommendations from this master plan. AACE International Class 5 cost estimates were developed for each item on the list based on limited definitions of scope developed by MWH and City staff. The expected accuracy range for the estimates are from - 20% to -50% on the low side and +30% to 100% on the high side, depending on technological complexity of the project, appropriate reference information, and the inclusion of an appropriate contingency determination. Ranges could exceed those shown in unusual circumstances (AACE International Recommended Practices and Standards). The estimates were developed for long-range capital planning purposes. Through a workshop setting, a funding priority of 1, 2, or 3 was assigned to each item on the project list by the City's staff. The funding priorities established are as follows: 1. Fiscally Constrained = projects that would be completed under a fiscally constrained funding scenario City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-11 2. Action Plan = projects in addition to those included in the Fiscally Constrained priority that would be completed under an action plan funding scenario 3. Vision = projects in addition to those included in the Fiscally Constrained and Action priorities that would be completed under an vision plan funding scenario For a more complete description of the funding priorities and the associated funding scenario assumptions see Volume 6 - Consolidated Capital Improvements Plan. Following assignment of the project funding priorities, City staff analyzed the project list to determine which projects would be completed using capital funds and which projects would be funded using operating funds. Further funding source identification for capital projects includes projects funded by the general Capital Improvements Program Fund, previously identified ongoing specific project funds, and future project bond funds. Further funding source identification for operating fund projects included determination of which City work group would provide the necessary funding including project management, water quality, water resources, water treatment, and utilities maintenance. Table 5-39 presents the project improvement list developed as part of the TWMP and includes a project description, identification as a capital or operations project type, estimated costs, funding priorities, funding source, planned funding year and comments. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-12 Table 5-39; Consolidated Recommended Improvements Project List Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost/Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments NE has broken underdrain 1 1 Betasso North lagoon sand replacement Capital $ 30,000 2005 $ 34,857 1 2012 Ongoing Betasso (replacement not included in price). WTF Project Interim measure until final residuals option is implemented. Note that original '05 Carollo estimate for pumped mixing was $791,000. New 2 2 Betasso Pump diffusion flash mixing Capital $100,000 1905 $116,190 2 NIA NIA estimate is for study plus minor modifications. Not required based on MWH WUMP analysis/recommendations. Step wise improvements will be made 3 3 Betasso C02 feed improvements Capital $ 294,000 2005 $ 341,599 2 TBD Operating Funds based on operations data using annual operating funds. These improvements are grouped Betasso WTF together and are one alternative for 4 4 Betasso Flocked inlet baffle Capital $ 35,000 2005 $ 40,667 1 2016 Bond Proceeds obtaining 46 MGD of facility capacity 2016 (32 MGD = approx. current capacity limit). These improvements are grouped Betasso WTF together and are one alternative for 5 5 Betasso Flocked serpentine baffles Capital $ 2,082,000 2005 $ 2,419,076 1 2016 Bond Proceeds obtaining 46 MGD of facility capacity 2016 (32 MGD = approx. current capacity limit). These improvements are grouped Betasso WTF together and are one alternative for 6 6 Betasso Floc equipment modifications Capital $1,361,000 2005 $1,581,346 1 2016 Bond Proceeds obtaining 46 MGD of facility capacity 2016 (32 MGD = approx. current capacity limit). These improvements are grouped Betasso WTF together and are one alternative for 7 7 Betasso Baffles between floc and sed Capital $ 842,000 2005 $ 978,320 1 2016 Bond Proceeds obtaining 46 MGD of facility capacity 2016 (32 MGD = approx. current capacity limit). These improvements are grouped Betasso WTF together and are one alternative for 8 8 Betasso Sedimentation basin effluent weirs Capital $ 97,000 2005 $112,704 1 2016 Bond Proceeds obtaining 46 MGD of facility capacity 2016 (32 MGD = approx. current capacity limit). DAF pretreatment improvements were 9 9 Betasso Pretreatment upgrades - DAF Capital $ 7,501,000 2005 $ 8,715,412 N/A NIA N/A determined to not be cost effective in Workshop #2. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-13 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description ow) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Plate settler pretreatment Pretreatment upgrades - Plate Betasso WTF improvements are a third alternative 10 10 Betasso Settlers Capital $ 6,550,000 2005 $ 7,610,445 2 2026 Bond Proceeds for obtaining 46 MGD of facility 2026 capacity ( 32 MGD = approx. current capacity limit) Betasso WTF Not using; currently Alum1PACL only. 11 11 Betasso Floc aid polymer addition Capital $ 235,000 2005 $ 273,047 1 2016 Bond Proceeds Jar testing should be commenced as 2016 soon as possible Oar test study included #21 below) The goal of the study would be to determine the optimized solution for pretreatment improvements to obtain Study to optimize pre-treatment Ongoing Betasso 46 MGD of capacity while resolving the 12 12 Betasso and residuals handling Capital $100,000 2010 $100,000 1 2013 WTF Project residuals capacity limitations of the facility to eliminate or reduce contract hauling requirements. (Note that this study can be combined with #20 and #21) Preference for residuals dewatering solution in Item #148. Could be re- 13 13 Betasso North engineered sand drying beds Capital $ 3,395,000 2005 $ 3,944,651 1 NIA N/A evaluated as part of pre- treatment/residuals management study. Betasso WTF Disinfection contact time issue; limited 14 14 Betasso Cleanvell No. 2 Baffle Wall Capital $ 209,000 2005 $ 242,837 3 2026 Bond Proceeds 10 approx. 10 MGD if Clearwell #1 off- 2026 line. Betasso WTF Staff also desire the addition of air 15 15 Betasso Filter rehabilitation (media, Capital $ 631,000 2005 $ 733,159 1 2016 Bond Proceeds scour for filter backwash if feasible. underdrain, valves etc.) 2016 Blowers could be located on the south side of the filter building. Betasso WTF Valves and actuators are 40 - 45 years 16 16 Betasso Replace/upgrade valves in filter Capital $160,200 2010 $160,200 1 2016 Bond Proceeds old and have reached the end of their piping gallery 2016 useful life. Lots of leaks. 4 valveslfilter, 8 filters. Betasso WTF Valves and actuators are 40 - 45 years 17 17 Betasso Replace actuators in filter piping Capital $ 209,600 2010 $ 209,600 1 2016 Bond Proceeds old and have reached the end of their gallery with electric actuators 2016 useful life. Lots of leaks. 4 valves/filter, 8 filters. 18 18 Betasso UV disinfection Capital $ 631,000 2005 $ 733,159 3 NIA N/A Consider in future, if needed for regulatory compliance Long-term option not considered 19 19 Betasso Membranes Capital $ 10,000,000 2005 $ 11,619,000 3 NIA N/A necessary in the current planning period. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-14 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Priority 2 = Basic parameters - 20 20 Betasso Monitor raw water quality 0&M $150,000 2010 $150,000 1 TBD Operating Funds turbidity, TOC, ORP; Priority 3 = Sophisticated parameters - emerging contaminants, etc. Study of lime and C02 addition Improvements were made in 2009, but 21 21 Betasso points for pH and alkalinity control 0&M $ 50,000 2010 $ 50,000 2 TBD Operating Funds effluent application points and controls and jar testing for floc aid polymer need to be studied for optimization. addition Existing is 250 kW Kohler diesel that is Betasso WTF not sufficient for any additional loads. 22 22 Betasso Replace back-up power generator Capital $ 253,800 2010 $ 253,800 2 2016 Bond Proceeds Staff desire new generator to be 2016 propane fueled to eliminate fuel storage issues (i.e. double containment). DAF pilot to determine feasibility DAF pretreatment improvements were 23 23 Betasso for improving residuals handling Capital $ 50,000 2010 $ 50,000 2 NIA N/A determined to not be cost effective in issues Workshop #2. Betasso WTF During workshop #3 it was determined 24 24 Betasso Carbon (PAC) feed system Capital $ 200,000 2010 $ 200,000 2 2016 Bond Proceeds that MWH estimate ($9900) was low. improvements 2016 More reasonable estimate for the full supersac feeder replacement is $200k. 25 25 Betasso Pipe gallery clean inglrepainting Capital $ 23,300 2010 $ 23,300 3 TBD Operating Funds 26 26 Betasso Chlorine scrubber demolition Capital $14,600 2010 $14,600 3 2012 Ongoing Betasso Create more need storage space. WTF Project Chemical (hypo, alum, fluoride) Betasso WTF Planning for replacement needs to 27 27 Betasso storage tank replacement Capital $ 209,700 2010 $ 209,700 2 2016 Bond Proceeds begin now. 2016 Re-piping is needed for better use of 28 28 Betasso needs to b Sodium h s to be reorite-feedpiped room Capital $ 6,600 2010 $ 6,600 2 2012 WTF Ongoing Project Betasso space, maintenance access and to accommodate future tank replacement Improvements to be identified by McKynstre energy audit were minimal. Miscellaneous energy efficiency Ongoing Betasso 29 29 Betasso improvements Capital $ 25,000 2010 $ 25,000 3 2012 WTF Project During Workshop #3, COB stated that another study is required. ($25,000 is reserved for each WTF) Staff desire the addition of a combined 30 30 Betasso Combined influent flow metering Capital $ 38,700 2010 $ 38,700 2 2013 Ongoing Betasso WTF Project (two influent pipelines and recycle) flow meter. Ongoing Betasso Standardize on magmeters. Current 31 31 Betasso Effluent flow meter replacement Capital $ 54,500 2010 $ 54,500 2 2013 venturi's not accurate or scalable over WTF Project the plant flow range. Miscellaneous security General Fund; Improvements identified in the VA; 32 32 Betasso improvements Capital $ 25,000 2010 $ 25,000 2 2012 $25,000 allocated details omitted from Master Plan for in 2012 security purposes. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-15 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments 33 33 Betasso Monitor system-wide and Betasso 0&M $ 50,000 2010 $ 50,000 2 TBD Operating Funds - Test system supply capacity from water demand Water Treatment BRWTP, with new pumps/meters. Test needs to be repeated during Perform stress test on flocked Operating Funds may/June runoff period - schedule for 34 34 Betasso basins 0&M $ 50,000 2010 $ 50,000 1 TBD Project 2011. (Note that this study can be Management combined with #12 and #21) Related to Item #11 above. (Note that Perform bench/pilot test of cationic Operating Funds - 35 35 Betasso polymer 0&M $ 50,000 2010 $ 50,000 1 TBD Water Treatment this study can be combined with #12 and #21) Betasso WTF See tab "OPCC - Solids Dewatering 36 148 Betasso Solids Dewatering Facility Capital $ 2,858,000 2010 $ 2,858,000 1 2016 Bond Proceeds Facility" for detailed cost estimate 2016 Betasso WTF 37 149 Betasso Filter surface wash replacement Capital $ 266,400 2010 $ 266,400 1 2016 Bond Proceeds MWH cost estimate 2016 More maintenance friendly lime feeder needed. Workshop #3 discussions 38 150 Betasso Lime feeder replacement Capital $188,500 2010 $188,500 1 NIA NIA indicated the existing lime feeder was functioning as well as anything available. Issue will be revisited during 2016 bond project design process. Betasso WTF SCADA upgrades needed. Should 39 151 Betasso SCADA upgrades for chemical Capital $ 250,000 2010 $ 250,000 1 2016 Bond Proceeds include better to read data formats. feed and process control 2016 Final cost is dependent on scope of work included. Workshop No 3 - Decided new turbidity meters were not required 40 152 Betasso Laser turbidity meters on filter effluent Capital $ 60,000 2010 $ 60,000 N/A NIA N/A (cost was $5k each x 8 filters + $20k for install). No funding in planning period. Perform sampling and testing of waste streams flowing into waste Sampling and subesequent study to Operating Funds 41 36 Betasso/BRWTF impoundments to determine type of 0&M $ 30,000 2010 $ 30,000 1 TBD determine waste impoundment impoundment and if impoundment Water Treatment regulation impacts at both Betasso WTF and Boulder Reservoir WTF improvements are needed. Evaluate conducting a rapid toxicity 42 165 Betasso/BRWTF Evaluate Rapid Toxicity Test 0&M $ 5,000 2010 $100,000 3 TBD Operating Funds - test (bioluminescent assay) basline Water Quality and clibration to enable determination of contamination of treated water. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-16 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Requires further investigation related to pH adjustment, TOC removal, and DBP formation. C102 is currently considered overkill by staff. This item Boulder Reservoir is retained to help address taste and 43 37 BRWTF Pre-oxidation improvements Capital $1,888,000 2008 $ 2,101,155 2 2020 WTF Bond odor concerns although specific T&O Proceeds 2020 compounds have not been identified. Currently piloting potassium permanganate which would also help prevent spread of zebra mussels. Expand study to include other options. Upgrade effluent flow meter to mag Ongoing Boulder City staff repaired existing venturi 44 38 BRWTF meter Capital $ 60,000 2008 $ 66,774 2 2014 Rservoir WTF meter; long term vision includes Project replacement with magmeter Flow-pacing of 6-10 chemicals Automate Chemical Feed and Ongoing Boulder (caustic, alum, acid (new), fluoride, 45 39 BRWTF Process Controls Tuning Capital $ 20,800 2010 $ 20,800 3 2013 Rservoir WTF SumaClear.... replace/upgrade Project instrumentation, resolve sampling issues and flow metering Priority 2 = Basic parameters - 46 40 BRWTF Monitor Feeder Canal Capital $183,700 2010 $183,700 2 TBD Operating Funds - turbidity, TOC, ORP; Priority 3 = Water Quality Sophisticated parameters - emerging contaminants, etc. Improvements were made to make maintenance somewhat safer, but 47 41 BRWTF Canal Intake Improvements Capital $ 80,000 2000 $112,800 2 201012011 Boulder Feeder safety is still a concern. Additional Canal Project improvements are desired including metal access stair, corrosion control issues, and an automatic trash rack. Boulder Reservoir 48 42 BRWTF Install VFD's on High Service Capital $ 80,000 2000 $112,800 2 2013 High Service Goes with plant automation. Existing Pumps Pump Station estimate of cost appears low. Project Cost includes only 1st phase, Boulder Reservoir according to MWH 2003. Requires 49 43 BRWTF Washwater Pretreatment Capital $ 617,000 2007 $ 686,659 3 2030 WTF Bond bigger tank; 10% recycle currently. Proceeds 2030 Item #43 is a new facility alternative to these upgrades. Boulder Reservoir 50 44 BRWTF Filter to Waste Capability Capital $ 250,000 2000 $ 352,500 3 2030 WTF Bond Likely tied to plant automation Proceeds 2030 Boulder Reservoir 51 45 BRWTF Plant Recycle Pretreatment Facility Capital $1,500,000 2000 $ 2,115,000 3 2030 WTF Bond Same as item #41, but new facility that includes decant water from lagoons Proceeds 2030 City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-17 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Determined at Workshop #3 that cost 52 46 BRWTF New Online Floc Monitoring Equipment Capital $ 35,000 2003 $ 46,715 3 NIA NIA outweighs any benefits. Therefore no funding planned. Only necessary if raw water quality degrades and/or Carter Lake Pipeline 53 47 BRWTF Presedimentation Capital $1,076,000 2003 $1,436,137 3 N/A N/A is not constructed. Should be considered with preoxidation item above (Item #40). Would require new/upgraded electrical 54 48 BRWTF UV Disinfection Capital $ 2,145,000 2003 $ 2,862,932 3 N/A N/A service. Could move up in priority if Crypfo increases. Not anticipated in 20-year CIP. Current system is only sufficient for Boulder Reservoir shutting down the plant in the event of 55 49 BRWTF Emergency Power Capital $ 400,000 2003 $ 533,880 2 2020 WTF Bond a power failure. Would need this with Proceeds 2020 automation. Estimate of cost seems law. Suggested in AWWA Peer Review. 56 50 BRWTF Membranes Capital $ 8,995,000 2003 $ 12,005,627 3 N/A N/A Potential long-term improvement. Not anticipated in 20-year CIP. Granular Activated Carbon Filter Boulder Reservoir Should be studied along with 57 51 BRWTF Cap Capital $ 250,000 2003 $ 333,675 3 2030 WTF Bond preoxidation (Item #40). Price seems p Proceeds 2030 low. High Service Pump Cavitation and Operating Funds - Should be evaluated with replacement 58 52 BRWTF Efficiency Study Capital $ 50,000 2010 $ 50,000 2 2012 Water Treatment or rebuild to get better efficiency equipment Boulder Reservoir 59 53 BRWTF Facility Automation Capital $ 4,300,000 2010 $ 4,300,000 3 2030 WTF Bond Includes $20.8K from #42 Proceeds 2030 Line old lagoons and evaluate structural integrity and site Need to study soon in light of new 60 54 BRWTF Capital $ 338,200 2010 $ 338,200 1 N/A regulations (See Comprehensive List drainage issues; determine waste impoundment regulation impacts Item #36) Ongoing Boulder Includes filter controls upgrades and 61 55 BRWTF Filter rehabilitation planning Capital $ 50,000 2010 $ 50,000 3 2014 Rservoir WTF evaluation of enclosing filters (similar Project to Betasso). May need rehab within 10 yrs. Boulder Reservoir 62 56 BRWTF Filter rehabilitation Capital $ 2,828,800 2010 $ 2,828,800 2 2030 WTF Bond Proceeds 2030 Ongoing Boulder 63 57 BRWTF Raw water pump VFDs Capital $ 75,000 2010 $ 75,000 3 TBD Reservoir Intake and Pumping Project City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-18 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Boulder Reservoir Security issue. Project will be 64 58 BRWTF Fiber optic line to RWPS and PLC Capital NIA 2010 NIA 3 2011 WTF Mid-Term completed in 2011 as part of the Mid- Improvements Term Improvements RWPS upgrades Project project. Improvements to be identified by Miscellaneous energy efficiency Ongoing Boulder McKynstre energy audit were minimal. 65 59 BRWTF improvements Capital $ 25,000 2010 $ 25,000 3 2012 Rservoir WTF During Workshop #3, COB stated that Project another study is required. ($25,000 is reserved for each WTF) Started up at 75th Street WWTP; 66 60 BRWTF Solar energy farm Capital NIA N/A NIA 2 NIA NIA considering program expansion. City would not construct or own the facility. Washwater recovery tank Boulder Reservoir 67 61 BRWTF Capital $ 500,000 2010 $ 500,000 3 2030 WTF Bond expansion Proceeds 2030 68 62 BRWTF Electrical power to canal intake Capital $100,000 2010 $100,000 2 201012011 Water System Safety/security issue - lighting location Security Project Upgrade/replace all pressure and Boulder Reservoir 69 63 BRWTF flow instruments Capital $150,000 2010 $150,000 3 2020 WTF Bond Standardize on Rosemount Proceeds 2020 Curb and gutter and drainage Boulder Reservoir 70 64 BRWTF improvements around plant Capital $100,000 2010 $100,000 3 2020 WTF Bond Proceeds 2020 Ongoing Boulder Existing paddle mixer is not providing 71 65 BRWTF Combined filter effluent post flume flash mix improvements Capital $ 80,300 2010 $ 80,300 2 2013 Rservoir WTF adequate mixing for CFE chemicals Project (caustic, fluoride, chlorine) As it currently stands, we need to make sure we have 3 empty tanks before we can accept a load of hypo. Boulder Reservoir Right now that doesn't pose much of a 72 66 BRWTF Additional chemical storage Capital $167,000 2010 $167,000 3 2020 WTF Bond problem but if we ramp up and start Proceeds 2020 treating more than 8-12 MGD, we could run into a problem with having enough hypo to get us through an unexpected delivery problem. Ongoing Boulder This could facilitate additional chemical 73 67 BRWTF Demo scrubber room equipment Capital $14,600 2010 $14,600 3 2013 Rservoir WTF storage Project Ongoing Boulder 74 68 BRWTF Upgrade filter controls Capital $ 53,300 2010 $ 53,300 2 2014 Rservoir WTF For improvement of reliability and update to current technology Project Energy conservation during winter. 75 69 BRWTF Cover filters Capital $ 460,800 2010 $ 460,800 3 NIA NIA Low priority. Not anticipated in 20-year CIP. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-19 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments See Comprehensive See Comprehensive See Comprehensive Boulder Reservoir 76 70 BRWTF Improved TOC removal Capital List Item #37 List Item #37 List Item #37 2 2020 WTF Bond See preoxidation item (#37) above Proceeds 2020 Ongoing Boulder 77 71 BRWTF Security improvements Capital $ 25,000 2010 $ 25,000 2 2013 Reservoir WTF ID specific projects from VA. Project; $25,000 allocated in 2013 Upgrade polymer feed system (dry Boulder Reservoir 78 71 BRWTF batching capability) Capital $100,000 2010 $100,000 3 2020 WTF Bond Proceeds 2020 Miscellaneous security Repeat of Comprehensive List Item 79 73 BRWTF improvements Capital NIA N/A N/A NIA NIA NIA #71. 80 153 BRWTF Emergency Power Alternative Capital $ 30,000 2010 $ 30,000 2 2013 Determine options for emergency Study power for BRWTF Evaluate Drinking Water Lab Operating Funds - 81 169 BRWTF Expansion and Needs 0&M $ 5,000 2010 $10,000 1 TBD Water Quality Evaluate Drinking Water Lab 82 170 BRWTF Capabilities, Needs, and 0&M $10,000 2010 $10,000 1 TBD Operating Funds Certifications by Constituent Water Quality Boulder Reservoir 83 172 BRWTF Replace filter valves and actuators Capital #REF! 2010 #REF! 2 2020 WTF Bond Proceeds 2020 Colorado River Water Boulder Feeder Canal Stormwater Capital $81,000 remaining available in the 84 141 Source Diversions - Phase 1 Capital $ 287,155 2010 $ 287,155 1 2011 Improvement 2011 budget for this project. Program Funds Colorado River Water Boulder Feeder Canal Stormwater No money budgeted in the 20 year CIP 85 142 Source Diversions - Phase 2 Capital TBD TBD 3 NIA NIA for this project contemplating Carter Lake Pipeline. $989,000 available in the 2011 budget Colorado River Water Capital for permitting and land acquisition. 86 143 Source Carter Lake Pipeline Capital $ 25,000,000 2010 $ 25,000,000 1 2017 and 2018 Improvement $2,608,367 budgeted in 2017 (design) Program Funds and $26,083,667 budgeted in 2018 (construction) Colorado River Water Capital $500,000 budgeted in 2017 (design) 87 144 Source Carter Lake Pipeline Hydro Capital $ 5,500,000 2010 $ 5,500,000 1 2017 and 2018 Improvement and $5,000,000 budgeted in 2018 Program Funds (construction) 88 145 Colorado River Water Farmer's Ditch Exchange Potential Capital $ 25,000,000 2008 $ 25,000,000 3 NIA NIA No money budgeted in the 20 year CIP Source Pipeline for this project. Capital $469,718 budgeted in 2021 (design) 89 146 Colorado River Water Source Wittemyer Ponds Capital $ 4,058,600 2010 $ 4,058,600 2 2021 and 2022 Improvement and $4,697,183 budgeted in 2022 Program Funds (construction) Colorado River Water Farmers Ditch Capacity Capital $106,090 budgeted in 2019 for 90 147 Source Restoration Capital $1,950,000 2010 $1,950,000 3 2019 Improvement evaluation. No other money budgeted Program Funds in the 20 year CIP for this project. City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-20 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Replace differential pressure Operating Funds - Chautauqua, Devils Thumb tanks 91 74 Distribution System sensors in system storage tanks 0&M $16,400 2010 $16,400 2 TBD Project currently use DP sensors translated to with level sensors Management a level which introduces inaccuracies Water System Security Project or Distribution Cost is dependent on number of WQ 92 75 Distribution System Add WQ stations Capital $100,000 2010 $100,000 2 2011 System Water monitoring stations Quality Improvement Project Add flow meter and controls to Sunshine shut down or significant Sunshine hydro facility 30" pipeline Sunshine changes in flow causes back-up into 93 76 Distribution System Flow meter and feedback control Capital $ 48,000 2010 $ 48,000 3 2017 Transmission Pipe Betasso clear well, and bypass valve loop for control of bypass valves Project must be manually opened. Flow meter during hydro shutdown would allow for proactive adjustments to be made. Rehabilitation/Replacement of Sunshine 94 77 Distribution System control system at Sunshine PRV Capital $192,400 2010 $192,400 3 2017 Transmission Pipe Project Base further study and necessary 95 78 Distribution System Treated water reservoir mixing 0&M $ 76,400 2010 $ 76,400 1 TBD Operating Funds - improvements on hydraulic modeling improvements Water Quality results and system water quality monitoring. Miscellaneous security Ongoing Water 96 79 Distribution System improvements Capital $ 25,000 2010 $ 25,000 2 TBD System Security ID specific projects from VA. Project Cherryvale pump station project 97 80 Distribution System Cherryvale Pump Station Capital NIA 2010 NIA 3 NIA NIA complete - no further upgrades needed for current planning period. Iris pump station project complete - no 98 81 Distribution System Iris Pump Station Capital NIA 2010 N/A 3 NIA NIA further upgrades needed for current planning period. 99 82 Distribution System Kohler Storage Tank Capital $ 920,000 2010 $ 920,000 3 2015-2016 NIA $1,100,000 to Reroof Kohler in 2016- 2017 Chautauqua Structural evaluation of double T shear 100 83 Distribution System Chautauqua Storage Tank Capital $ 870,000 2010 $ 870,000 2 2011 Storage Tank tabs, seal shrinkage cracks, coat roof Project 2011 vents, evaluate internal lining (previous lining estimate was $213,000 in 2002) Capital 101 84 Distribution System Betasso Storage Tank Capital $ 250,000 2008 $ 265,225 2 2017 Improvement Paint outside and possible cathodic protection.$281,377 in 2017 Program Funds Capital Paint interior and possible cathodic 102 85 Distribution System Gunbarrel Storage Tank Capital $ 250,000 2008 $ 250,000 2 2013 Improvement protection $250,000 in 2013 Program Funds City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-21 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Ongoing Waterline Work will be funded as part of on- 103 86 Distribution System Zone Isolation Valves Capital Included in Item #88. 2008 Included in Item #88. 1 TBD Replacement Project going waterline replacement project.. Pro Develop cathodic protection standards 104 87 Distribution System Cathodic Protection Capital $ 25,000 2010 $ 25,000 1 TBD Ongoing Cathodic for new transmission pipelines and Protection Project develop program to add cathodic protection. Ongoing Waterline No escalation of costs from 2008 - 105 88 Distribution System Waterline Replacement Capital $2,100,000 2008 $ 2,100,000 1 2011-2032 Replacement 2013. Project $267,615 for pipe inspection, minor Sunshine repair work and installation of access 106 89 Distribution System Sunshine Transmission Pipe Capital $ 999,728 2010 $ 999,728 1 2011 and 2013 Transmission Pipe manholesin 201; another $800,000 in Project 2013 for manways and lining rehabilitation. See asset See asset See asset Zone 1-3 Modeling indicates no large capital 107 90 Distribution System Zone 1 Transmission Facilities Capital management NIA management 3 management Transmission improvements required. Improvements and funding based on asset spreadsheets spreadsheets spreadsheets Projects management spreadsheets. See asset See asset See asset Zone 1-3 Modeling indicates no large capital 108 91 Distribution System Zone 2 Transmission Facilities Capital management NIA management 3 management Transmission improvements required. Improvements spreadsheets spreadsheets spreadsheets Projects and funding based on asset management spreadsheets. See asset See asset See asset Zone 1-3 Modeling indicates no large capital 109 92 Distribution System Zone 3 Transmission Facilities Capital management NIA management 3 management Transmission improvements required. Improvements and funding based on asset spreadsheets spreadsheets spreadsheets Projects management spreadsheets. 110 93 Distribution System Boulder Canyon - Orodell to Capital $ 500,000 1 2011 Orodell to 24" pipeline replacement. Fourmile Fourmile Project Ongoing 111 94 Distribution System Automated Meter Reading Capital $ 500,000 2008 $ 530,450 1 2011-2013 Automated Meter Reading Project 112 95 Distribution System Maxwell Tank Improvements Capital $ 920,000 2008 $ 920,000 2 2020 Maxwell Storage Roof replacement. Tank Project 113 96 Distribution System Oradell Hydroelectric 12-inch Capital $ 8,000 2010 $ 8,000 2 2011 Orodell to Isolation BFV (downstream) Fourmile Project 114 97 Distribution System Orodell New I&C Battery Back-Up 0&M $10,000 2010 $10,000 1 TBD Operating Funds - Water Resources 115 98 Distribution System 101 Pearl Street Turbine Generator Capital $ 200,000 2008 $ 200,000 3 2019 Turbine Generator Improvements Project Operating Funds - 116 101 Distribution System Maxwell Reservoir 0&M $10,000 2010 $10,000 1 TBD Utilities Crack/joint repair, recoating Maintenance City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-22 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description 0&M) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Maxwell Reservoir Regrading and Operating Funds - 117 102 Distribution System Erosion Control 0&M $ 5,000 2010 $ 5,000 1 TBD Utilities Erosion control Maintenance Paint inside and outside. $1,250,542 118 103 Distribution System Devils Thumb Reservoir Capital $ 814,161 2010 $ 814,161 3 2022 General Fund budgeted in 2022 from asset management spreadsheet. Tanks appear to be in good condition, Operating Funds - regular inspections should be 119 104 Distribution System Booton Reservoir 0&M $ 5,000 2010 $ 5,000 1 TBD Utilities continued, but no major costs Maintenance anticipated at this time. Vegetation control, bird nest removal, and bird screen installation. 120 105 Distribution System Pipeline Replacement Program Capital NIA NIA NIA N/A NIA N/A Duplication of Comprehensive List Item #88. 2010 TWMP modeling results indicate Further Investigation of Low 121 106 Distribution System Pressure and Potential Insufficient 0&M $ 30,000 2010 $ 30,000 2 TBD Operating Funds - some areas with these potential Fire Flow Capacities Water Treatment issues. Further investigation (study) is required to confirm and define extent. 122 107 Distribution System Kohler Reservoir Roof Capital $ 918,900 2007 $1,063,443 1 2016 Kohler Storage Kohler roof in poor condition, but not Tank Project as bad as Chautauqua Chautauqua Chautauqua roof is in extremely poor 123 108 Distribution System Chautauqua Reservoir Roof Capital $ 619,020 2007 $ 716,392 2 2011 Storage Tank condition Project 2011 Capital 124 161 Distribution System Chautauqa Reservoir Lining Capital $ 267,600 2010 $ 267,600 2 2022 Improvement Program Funds 125 162 Distribution System Maxwell Hydroelectric Building 0&M $10,000 2010 $10,000 1 TBD Operating Funds - Inspection and Repair Plan Water Resources 101 Pearl Street PRV Site Grading 126 163 Distribution System and Parking Turn Area 0&M $ 5,000 2010 $ 5,000 2 TBD Operating Funds - Water Resources Improvements Evaluate conducting an S04 tracer Operating Funds - study to confirm zone boundaries, 127 164 Distribution System Evaluate S04 Tracer Study 0&M $ 7,000 2010 $ 7,000 2 TBD Project mixing zone characteristics, and to Management determin origin of treated water at a given location in the system. 128 166 Distribution System DBP Formation Potential Study 0&M $ 50,000 2010 $ 5,000 2 TBD Operating Funds - Water Quality 129 167 Distribution System Evaluate Value of HPC Monitoring 0&M $ 5,000 2010 $ 8,000 2 TBD Operating Funds - Water Quality City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-23 Final Item Comprehensive Type (Capital or Funding Planned No. List Item No. Facility Project Description ow) Cost[Value Date of Initial Cost Current Cost (2010) Priority Funding Year Funding Source Comments Evaluate distribution system water quality parameters such as water age (using results from different operating scenarios in 130 168 Distribution System Water Age Modeling 0&M $10,000 2010 $15,000 1 TBD Operating Funds - the hydraulic model) and Water Quality chlorine residual and how these parameters compare to Best Practices. Recommendations for optimized monitoring and sampling plan. 131 171 Distribution System Test Drinking Water in Areas of 0&M $ 5,000 2010 $ 5,000 3 TBD Operating Funds - Groundwater Contamination Water Quality City of Boulder Final Draft Treated Water Master Plan (February 2011) Page 7-24 momomm page (February2411) A-1 Utility of Boulder Final Draft Water Master plan City A•~~ d' • peniX City of Boulder Water Treatment Operations Regulatory Requirements PWSID - CO-0107152 Revised - 05-13-10 - Format only -vlj Unit Process Parameter MCL Action to be taken Anytime there is a MCL exceedance contact a supervisor immediately and the State as appropriate Alum Summaclear Lime Pre- Chlorine chemical Zeta Potential Feed Zeta pH Zeta Alkalinity Streaming Current Sed Basins Flow Split Turbidity Post Basins pH Chlorine Run time LOH 4 gal/min / sq ft continuous Rate 5 gal/min / sq ft short term - Take out of service and backwash Initial < 0.5 NTU Win 4 hrs. of filter start-up - If > two consecutive 15 min readings > Filters Turbidity < 1 NTU Win 15 min filter start-up either limit must report - see regulation spike - Partnership suggests < 0.3 Win 4 hrs. of backwash Turbidity < 0.5 NTU Take out of service and backwash Never > 5 NTU hydraulic change/filter Particle Counts < 0.3 NTU Combined Turbidity in 95% of samples Shutdown plant and call supervisor if CFE Never > 1.49 NTU turbidity > 0.5 NTU Filter Effluent Particle Counts (Flume) Chlorine pH Alkalinity 15 - 98 mg/L - CDPHE designated Adjust lime as needed Cannot exceed more than 9 days in 6 mo. period Adjust Carbonic acid feed rate as needed; pH Cannot exceed more 7than 9 days (SMCL) in 6 mo. period If pH exceeds 8.2 for three hours notify WQ supervisor Finished Flouride 4.0 mg/l (MCL) 2.0 mg/I (SMCL) Adjust pump setting not < 0.2 mg/I for more than 4 hrs. Adjust set point or run pump manually; Chlorine or In distribution system at any point there must < 4.0 mg/I in distribution system be > trace in 95% of samples and < 4.0 mg/I Turbidity Color Page A-1 City of Boulder Water Treatment Operations Internal Targets Betasso WTF PWSID - CO-0107152 Revised: 912007 Targets - per GG and RC (05.13.10 format-vij) Unit Process Parameter InternalTar et Action to be taken Anytime there is a MCL exceedance contact a supervisor immediately and the State as appropriate Alum As needed to meet Zeta Potential and Adjust chemical flow rates to meet Zeta Zeta pH Potential, pH and Alkalinity; When feeding Summaclear Sumaclear do not dose < 2.5 mg/I Lime Chlorine Meet pre-filter target Only used if Pre-oxidant needed (i.e_ high Pre- (if used) influent Turbidity) chemical Zeta Potential Slightly minus 3 works well) Adjust alum or suma to achieve/maintain Feed zeta targets Zeta pH 6.4-6.8 Adjust coagulant or pre-Carbonic acid Zeta Alkalinity > 9 mg/I If < 9.0 increase or start feeding Sumaclear to improve settling in basins. Streaming 0 Current Sed Basins Flow Split Equal between basins Turbidity < 1.0 NTU Filters fail if turbidity > 3 NTU Post Basins pH Maintain low residual to decrease DBP Chlorine < 0.2 mg/l (only if feeding pre-CL2) formation; Adjust re-chlorine as needed Run time < 48 Hours LOH Rate 5gal/min/sqft or < 5 MGD - Take out of service and backwash Initial < 1 NTU w/in 15 min - If > two consecutive 15 min readings > Turbidity of filter start-up either limit must report - see regulation Filters spike - Partnership suggests < 0.3 w/in 4 hrs. of backwash Turbidity < 0.15 NTU Take out of service and backwash hydraulic <1.0 MGD change/filter Particle Less than 100 total counts Counts Turbidity < 0.1 NTU Shutdown plant and call supervisor if CFE turbidity > 0.5 NTU Combined Particle Filter Counts Less than 100 total counts Evaluate filter performance Effluent 0.1 + 0.1 mg/L Adjust post Sed Basin chlorine (or pre if not (Flume) Chlorine (0.4 + 0.1 when cleaning basins) using post Sed Basin) pH Alkalinity 45 + 3.0 mg/L Adjust lime as needed Adjust Carbonic acid feed rate as needed; pH 7.8+0.2 If pH exceeds 8.2 for three hours notify WQ supervisor Flouride 0.90 + 0.1 mg/L Adjust pump setting Finished Chlorine Adjust set point or run pump manually; Residual 1.0+0.1 mg/L In distribution system at any point there must from Hypochlorite be > trace in 95% of samples and < 4.0 mg/I Turbidity < 0.1 NTU Confirm with grab - refer to SOP Color Increase Pre-chemicals (especially Sumaclear Page A-2 City of Boulder Water Treatment Operations Internal Targets Boulder Reservoir WTF at 63rd Street PWSID - CO-0107152 revised: 5/13/2010 - format only - vii Unit Process Parameter InternalTarget Action to be taken Anytime there is a MCL exceedance contact a supervisor immediately and the State as appropriate Pre- Alum As needed to meet Zeta Potential,Daf PH Adjust chemical flow rates to meet Zeta Potential/DAF PH chemical Sumaclear 8036 Feed Only used if Pre-oxidant needed for Mn or Hypochlorite 0.5 + 0.2 mg/L (In zeta) high influent Turbidity Turbidity < 100 NTU Adjust coagulant feed rate or begin Raw water shutdown as needed Manganese < 5 mg/L > 5 mg/I start pre miox at post static mixer < 3 mg/I Dissolved Oxygen/ Test Dissolved oxygen > 3 mg/L manganese level daily Da Shift Zeta Potential -4+1 Adjust alum or suma to achieve/maintain zeta DAF Zeta pH 6.5-6.8 Adjust coagulant Turbidity < 1.0 NTU If > 1.0 NTU for more than 2 hrs - shut Run time 60 Hours Filters Rate < 5 gal/min / sq ft or < 5 MGD Add filters to meet plant flow target - Take out of service and backwash - If > two consecutive 15 min readings > Initial Turbidity < 1 NTU Min 15 min either limit must report -see regulation Spike of filter start-up - Partnership suggests < 0.3 Win 4 hrs. of backwash Turbidity < 0.15 NTU Backwash filter if greater Differential Flow < 1.0 mgd Filter conditionin 3 hrs rest Particle counts < 100 total counts Backwash filter if greater Combined Turbidity Check all other parameters begin filter Filter < 0.1 NTU evaluation Effluent Chlorine 0.4 ± 0.2 mg/L Adjust post DAF chlorine (or pre, if post Flume DAF not in use) Chlorine 1.1 + 0.1 mg/l Post Flume - Adjust to achieve desired finished value pH 7.8 ± 0.2 mg/I Alkalinity 15 - 98 mg/L Finished pH 7.8+0.2 Feed Alum and/or Caustic to achieve desired finished level Flouride 0.90 + 0.1 mg/L Adjust pump setting - Adjust set point or run pump manually to Chlorine achieved desired finished level Residual 1.0 ± 0.1 mg/L - Must be > trace in 95% of samples and from Hypochlorite < 4.0 mg/I at any point in the distribution system Turbidity < 0.25 NTU Confirm with grab - refer to SOP Manganese < 0.03 mg/L Increase Pre DAF C12/Source Selection Page A-3 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page B-1 Appendix B: Additional Figures from Evaluations of Water Quality and Betasso Water Treatment Facility Performance M M ~N~N Betasso WTF High Flow Days (>24 mgd) Flowrate and Raw Water Turbidity 12 - - - - - I 40.0 10 35.0 30.0 8 _ 25.0 z ~ :a 6 20.0 2 Mo L 3 O H LL 15.0 4 - 10.0 2 5.0 A.JAL AA, 0 - -r r r r r~ -t t:- r r r t r r r r I 0.0 -*-Barker Ave Turbidity Lakewood Ave Turbidity tAve Flow (mgd) Page B-1 Betasso WTF Lakewood Turbidity May - July Data, 2006-2009 10.00 - _ 9.00 8.00 ■ X 7.00 i 6.00 - ~ x z 5.00 X X ♦ 2006 ■ 2007 ~ x ~ 4.00 x X 2008 ■ X 2009 x x 3.00 ■ x x 2.00 ♦ ~C ■ A wX* X 1.00 0.00 - - - 12-A - pr 2-May 22-May 11-Jun 1-Jul 21-Jul 10-Aug Page B-2 Betasso WTF Barker Turbidity May - July Data, 2006-2009 12.00 X 10.00 - 8.00 Z ♦ 2006 6.00 I ~ - a ■ 2007 L 2008 3 ~ X X A X 2009 4.00 ~Xx ■ XX xx ■ X X ■KXX ■ Alm A ..A~.. A ~y ♦ III _ ♦ ~ ♦ Ili 2.00 r ♦ ♦ X I 0.00 12-Apr 2-May 22-May 11-Jun 1-Jul 21-Jul 10-Aug Page B-3 Betasso WTF Lakewood Turbidity Probability Plot May-July Data - 2006-2009 8.00 7.00 - 6.00 5.00 Z 4.00 L 3 3.00 2.00 1.00 "WNW - now- 0.00 I i 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 -0-2006 --W-2007 2008 --)4-2009 Page B-4 Betasso WTF Barker Turbidity Probability Plot May-July Data - 2006-2009 7.00 -I I 6.00 5.00 4.00 Z T r_ .a 3.00 3 H 2.00 1.00 0.00 ~ - - - 0.6 0.7 0.8 0.9 1 0 0.1 0.2 0.3 0.4 0.5 __*._2006 --W-2007 2008 -06-2009 Page B-5 Betasso WTF Source Water Color - Probability Plot 120 100 80 L c 60 u 40 20 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 -*--Barker Color tLakewood Color Page B-6 Betasso WTF Lakewood - Color and Turbidity 100 10 90 ♦ 9 80 • 8 70 ♦ i ♦ ♦ 7 60 • ♦ ♦ 6 _ f ~ c w 1 z 50 - 5 r o s ♦ M O t• • • w 40! ♦ ♦ ♦ ♦ 4 t- 30 : . ♦ • ♦ • ♦ i ♦ • 3 20 • ♦ ♦ • 2 10 r~ ~ ♦ ♦ 1 0 - - 0 9/1/02 1/14/04 5/28/05 10/10/06 2/22/08 7/6/09 11/18/10 Color ♦ Turbidity Page B-7 Betasso WTF Barker - Color and Turbidity 120 - 12 100 - 10 80 8 F H z • 60 6 r o • ~ ♦ ♦ • 40 ♦ ♦ ♦ 4 20 2 • ♦ 0 • ♦ • ♦ • 0 9/1/02 1/14/04 5/28/05 10/10/06 2/22/08 7/6/09 11/18/10 • Color • Turbidity Page B-8 Betasso WTF High Flow Days (>24 mgd) Settled Water Average Turbidity - Probability Graph 1.60 - - - - 1.40 1.20 _AA 1.00 z 0.80 3 H 0.60 0.40 0.20 - 0.20 0.40 0.60 0.80 1.00 1.20 --*-Basin #1 Ave Turbidity --M-Basin #2 Ave Turbidity Basin #3 Ave Turbidity Basin #4 Ave Turbidity Page B-9 Betasso WTF Barker High Turbidity Days (>4 NTU) Settled Water Average Turbidity Probability Graph 1.60 - - - - 1.40 1.20 - 1.00 ,i Ap~ z 0.80 0.60 3 0.40 0.20 0.00 - - - 0.20 0.40 0.60 0.80 1.00 1.20 -0.20 - - - Basin #1 Basin #2 -*-Basin #3 Basin #4 Page B-10 Betasso WTF Lakewood High Turbidity Days (>4 NTU ) Settled Water Average Turbidity Probability Graph 1.40 1.20 1.00 0.80 z T 'o :o 0.60 i ~ I 0.40 0.20 0.00 - - - 0.20 0.40 0.60 0.80 1.00 1.20 -Basin 41 Basin #2 --o-Basin #3 Basin #4 Page B-11 Betasso WTF Basin # 1 Settled Turbidity Probability Plot May-July Data - 2006-2009 1.60 1.40 1.20 1.00 z lot 0.80 =a L 3 0.60 0.40 0.20 0.00 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 --4--2006 --W-2007 2008 -06--2009 Page B-12 Betasso WTF Basin # 2 Settled Turbidity Probability Plot May-July Data - 2006-2009 1.60 1.40 1.20 1.00 - - z 0.80 ~a 0.60 - 0.40 0.20 0.00 - 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 -0.20 --*--2006 -0-2007 2008 -0ce 2009 Page B-13 Betasso WTF Basin # 3 Settled Turbidity Probability Plot May-July Data - 2006-2009 1.40 - - - 1.20 1.00 0.80 1 z 0.60 0.40 0.20 0.00 - - 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 -0-2006 -11-2007 2008 -0-2009 Page B-14 i Betasso WTF Basin # 4 Settled Turbidity Probability Plot May-July Data - 2006-2009 1.40 - - - 1.20 1.00 ~ 0.80 z = 0.60 - - 0.40 - 0.20 0.00 - - - - 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 --$--2006 f 2007 2008 --)~--2009 Page B-15 Betasso WTF Filters High Flow Cases (>24 MGD) Average Filter Turbidity Probability Plot 0.10 - 0.09 0.08 - - - - 0.07 Z 0.06 T r 'G 0.05 b c°DC 0.04 m - a 0.03 0.02 - 0.01 0 0.2 0.4 0.6 0.8 1 1.2 Filter 1 (Filter 2 Filter 3 -)E-Filter 4-Filter 5 Filter 6 Filter 7 Filter 8 Page B-16 Betasso WTF Filters Rate of Filtration vs. Maximum Filter Turbidity 3 2.5 . At 0 - a 2 z a + E 1.5 E E 1 X ♦ _ 0.5 rb~~ ~~~I"'4`'a ~~'J ,~i ~ I`°I ~ If li ~r -•Y ~ I ,~~'~I I 1 ,I~~ r~~ 0 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 Rate of Filtration (gpm/ft2) ♦ Filter 1■ Filter 2 Filter 3 X Filter 4 X Filter 5 Filter 6 Filter 7 Filter 8 Page B-17 Betasso WTF Filters High Flow Cases (>24 MGD) Maximum Filter Turbidity Probability Plot 0.30 0.25 3 ? 0.20 a Note: There are 5 data points above 0.31 NTU, 3 max = 2.5 NTU, not E 0.15 shown for clarity E 3 E X M 0.10 0.05 0 0.2 0.4 0.6 0.8 1 1.2 -4-Filter l f•Filter 2 Filter 3 --o--Filter 4 Filter 5 Filter 6 Filter 7 Filter 8 Page B-18 Betasso WTF 2006: May - July Filter Turbidity and Plant Flow 0.100 - 40.0 0.090 A ~ 35.0 0.080 x • • 30.0 0.070 • X - 25.0 0.060 t- I- 0.050 W20.0 0 .0 x m ♦ x T . T Y • x c 0.040 JIF C ■ a R~ ~ ♦ 15.0 •j 0.030 x ~X:' kX X X xx 0 - 10.0 X lax ex, , 0.020 - m -a Z% • • 5.0 0.010 0.000 0.0 12-Apr 2-May 22-May 11-Jun 1-Jul 21-Jul 10-Aug ♦ filter 1 ■ Filter 2 Filter 3 X Filter 4 ;k Filter 5 Filter 6 Filter 7 Filter 8 -•-Betasso Plant Flow (mgd) Page B-19 Betasso WTF 2007: May - July Filter Turbidity and Plant Flow 0.1 30.0 0.09 ♦ 25.0 0.08 A A t A I 0.07 ~ xX ♦ % 20.0 0.06 ~K A )k' )K X* ;6K E ■ x *'K x )~K ♦)C 0.05 ♦ 15.0 c + ♦ ■ LL ■ + 0.04 -11 a • X + X + T r 10.0 0.03 - AL X X=X *_X X _x >i 0.02 ~ 5.0 0.01 0 1 - - - 0.0 12-Apr 2-May 22-May 11-Jun 1-Jul 21-Jul 10-Aug ♦ filter 1 ■ Filter 2 d Filter 3 X Filter 4 X Filter 5 Filter 6 Filter 7 Filter 8 -•-Betasso Plant Flow (mgd) Page B-20 Betasso WTF 2008: May - July Filter Turbidity and Plant Flow 0.090 - 35.0 0.080 - • 30.0 0.070 • r• : A 11 X ♦ r• ♦ ,i•••.••••.•.•• 25.0 0.060 • • . Z 0.050 • r• • • • ■ ! 20.0 L I, LL X~. 41 3 0.040 ♦ ti • A f ` 15.0 i ♦ X d-LX 0.030 • > + X X AX X )a X` X _ 10.0 ASK • 0.020 - X 5.0 0.010 - 0.000 0.0 12-Apr 2-May 22-May 11-Jun 1-Jul 21-Jul 10-Aug ♦ Filter 1 ■ Filter 2 Filter 3 X Filter 4 Filter 5 Filter 6 Filter 7 Filter 8 -•-Betasso Plant Flow (mgd) Page B-21 Betasso WTF 2009: May - July Filter Turbidity and Plant Flow 0.09 - 35.0 • 0.08 30.0 0.07 ■ - A A --A ■ - 25.0 0.06 0.05 - 20.0 m > 3 0 1 • Z ma 0.04 15.0 eg ~ X~ X ♦ ao 0.03 46-_ .v XC~; , ',r -f- - - - 10.0 0.02 5.0 0.01 0 - - 0.0 12-Apr 2-May 22-May 11-Jun 1-Jul 21-Jul 10-Aug ♦ Filter 1 ■ Filter 2 Filter 3 X Filter 4 X. Filter 5 Filter 6 Filter 7 Filter 8 --*--Plant Flow Page B-22 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page C-1 Appendix C: Water Utility Master Plan Hydraulic Modeling Results MEMO MWH MEMORANDUM BUIIOING A BETTER WORLD To: City of Boulder Date: August 16, 2010 From: MWH Subject: Water Utility Master Plan Hydraulic Modeling Results L llltroductioll The following memorandum summarizes the analysis of the City of Boulder's water distribution system as part of the Boulder Treated Water Master Plan update. The work summarized in this memorandum was developed based on the modeling approach developed by MWH and the city prior to the start of this task. 2. Overview The City of Boulder's water distribution system was evaluated to understand system performance under current and future conditions and to identify system deficiencies. Model results were analyzed to determine if the water distribution system met the reliability criteria as shown in Table 1 below. Table 1- Reliability Criteria Category Criteria Pressure 40 - 80 psi Target range for normal operating pressure 150 psi Maximum target pressure; Note: Pressures at some existing areas in the system reach over 160 psi. 20 psi Minimum allowable pressure during fire flow under a maximum day demand conditions Velocity 10 feet per second Maximum velocity under normal operating conditions Head 10 feet/1000 feet Maximum headloss under normal operating Loss conditions In addition to the criteria listed above, the water distribution system was evaluated to further understand the need for pressure zone modifications, areas of high water age and the systems operating during system failure scenarios. The following sections provide a summary of the work performed to evaluate the city's water distribution system. Recommended improvements and further analysis are presented at the end of this memorandum. Page C-1 August 16, 2010 Hydraulic Modeling Results Page 2 3. Existing Distribution Network Model Calibration 3.1. Model Calibration Overview The city has been using a computer model to simulate system hydraulics and operation of the water distribution since before 1980 when the first Boulder water distribution model was developed in KYpipe. As part of the 2000 City of Boulder Treated Water Master Plan, the model was improved and calibrated using field verified pressures and fire flow tests. In 2005, the city's model was integrated into the MWH Soft InfoWater software and was upgraded to an all-pipes model. Since that time the city has been maintaining and updating the water distribution model and routinely comparing SCADA data with model results to verify the model output. The model has also been enhanced to perform 24-hour and 30-day extended period simulations (EPS) and includes rule-based logic that allows the model to operate similar to the approach taken by the operators within the city. The model used for this distribution system evaluation was most recently calibrated by the city for the IDSE Report prepared in 2006. The city provided MWH with a copy of the calibrated EPS model and corresponding model set-up and calibration documentation. Model documentation provided by the city for the model calibration is provided in Attachment 1. MWH reviewed these documents and did not perform any additional calibration prior to performing the distribution system evaluation. A summary of the calibration review is provided in the next section. 3.2. Model Calibration Review The EPS model calibration performed by the city for the IDSE Report included a comparison of SCADA data and model results for a 24-hour and 30-day period in 2006. Results provided by the city show that a comparison of model versus SCADA water levels in the Gunbarrel, Maxwell and Chautauqua tanks for a 24-hour period are in reasonable agreement. However results from the 30- day simulation show that while the range of tank water levels are in general agreement between the model and SCADA data, the timing of the water levels and the shape of the plots are different. At the time of the model calibration, city staff attributed this difference to the fact that the Boulder water distribution system is manually operated with each operator having a slightly varied approach to meeting system pressures and flows. As a result, over a 30-day period there will be a continual change in the daily system operation that could not be replicated with the rules-based controls established in the model. The city staff felt that the boundary conditions adequately represent the real system and that the rule-based controls used by the model reflect a reasonable approach to operating the system. In addition, no significant changes were made to the underlying assumptions used during the latest model calibration, such as C-factors, minor losses, and system configuration. For these reasons the city staff agreed that the model adequately represented the water distribution system and was a good tool to understand the system hydraulics. 3.3. Model Calibration Comments and Recommendations Based on review of available data provided by the city, MWH concludes that a reasonable approach was used to verify that the model could produce results that are consistent with flow, pressure and tank level ranges that are seen in the Boulder water distribution system when appropriate system inputs are used in the model. The EPS model calibration performed by the city for the IDSE Report could be further refined by performing targeted field testing to verify the Page C-2 August 16, 2010 Hydraulic Modeling Results Page 3 model's ability to replicate system conditions under a variety of demand conditions. Specific examples include the following: • Perform distribution system pressure monitoring to compare model and actual pressures seen across the distribution system; • Conduct fire flow simulations to compare the model and actual system's response to stress and confirm local head-loss; and • Perform loss-of-head tests along targeted pipe segments to refine roughness factors (c- factors) in areas to improve agreement between model and system flow splits (i.e. at Betasso WTF) and tank levels. Additional field-verified model calibration would enable the city to remain confident in the model's ability to represent system hydraulics and maintain the city's investment in the water distribution system model as a tool for planning and operation. 4. Distribution System Evaluation 4.1. Overview The distribution system evaluation was performed by using a both steady-state and extended period simulation analysis in the calibrated hydraulic model under a variety of demand conditions. The city and MWH established a methodology for performing the hydraulic analysis which was designed to specifically meet the objectives outlined above. This methodology is summarized in a memorandum dated June 29, 2010. The city provided MWH with a model file in the MWH Soft InfoWater software that contained model scenarios for use in the evaluation. The model simulations provided by the city are outlined in Table 2. A summary of the model boundary conditions and comparison with SCADA for the model provided by the city are provided in Attachment 2. Table 2 - City Provided Model Scenarios Demand Scenario Type Peaking Factor Model Scenario from City (SS or EPS) (PF) i Demand _ Existing Demands Maximum Day SS PF of 2.6 Scenario Name: 43.13 MGD MAXDAY SS Peak (Max) Hour SS PF of 2.7 Scenario Name: 44.79 MGD MAXDAY_SS Minimum Month 30 Day EPS PF of 0.6 Scenario Name: 9.36 MGD MINMONTH EPS Maximum Month 30 Day EPS PF of 2.05 Scenario Name: 32.1 MGD MAXMONTH EPS 4.2. Model Scenarios MWH adapted the model files provided by the city to create the ten model scenarios that were used for the distribution system evaluations. Each of the scenarios are outlined in Table 3 below and discussed in more detail in the following section. The failure scenarios are outlined in Table 4. Page C-3 August 16, 2010 Hydraulic Modeling Results Page 4 Table 3 - Model Scenarios for Distribution System Evaluation Model Demand M.pdel used Me Master New Model Scenario Scenario lanning Tasks Scenario Existing Demands =18.26 MGD* Water Age Minimum PF of 0.6 30 Day EPS Use MINMONTH_EPS Analysis Month 10.95 MGD with demand scaled Water Age Maximum PF of 2.0 30 Day EPS Use MINMONTH_EPS Analysis Month 36.52 MGD with adjustments for Max Month 2035 Demands = 20.9 MGD* Pressure Zone Minimum PF of 0.6 7 Day EPS Adapt from MINDAY Analysis Day 12.54 MGD MINMONTH_EPS using Failure WUMP 2035 demand MINDAYFI Scenario 1 distribution and SS option Failure MINDAYF5 Scenario 5 Fire Flow Maximum PF of 2.6 SS Adapt from MAXDAY_SS MAXDAY35 Analysis Day 54.34 MGD using WUMP_2035 demand Failure Maximum PF of 2.6 7 Day EPS distribution MAXDAYF4 Analysis Day 54.34 MGD Scenario 4 Hydraulic Peak Hour PF of 3.6 SS PKHR2035 Capacity 75.24 MGD Analysis Failure Maximum PF of 2.0 30 Day EPS Adapted from MAXMONF2 Scenario 2 Month 42.8 MGD MAXMONTH_EPS with demand Failure Maximum PF of 2.0 30 Day EPS Adapted from MAXMONF3 Scenario 3 Month 42.8 MGD MAXMONTH_EPS with demand Page C-4 August 16, 2010 Hydraulic Modeling Results Page 5 Table 4 - Failure Scenario Overview 1 Betasso WTF out of Minimum day demands being met entirely from the Boulder service Reservoir WTF through the Iris, Cherryvale, Maxwell and Kohler pump stations. 2 Sunshine pipeline out of Maximum month demands being met from the Boulder Reservoir service WTF and the Betasso WTF through the Canyon Pipelnie only, in combination with the Iris, Cherryvale, Maxwell and Kohler pump stations, hydros and PRVs as needed- 3 Boulder Reservoir WTF Maximum month demands being met entirely from the Betasso out of service WTF through the Maxwell, Kohler, Iris and Cherryvale hydros and PRVs as needed. 4 Canyon pipeline out of Maximum day demands being met from the Boulder Reservoir service WTF and the Betasso WTF through the Sunshine Pipeline only, in combination with the Iris, Cherryvale, Maxwell and Kohler pump stations, hydros and PRVs as needed- 5 Sunshine Pipeline and Minimum day demands being met from the Betasso WTF through Boulder Reservoir WTF the Canyon Pipeline only and the Maxwell, Kohler, Iris and out of service Cherryvale hydros and PRVs as needed. Page C-5 August 16, 2010 Hydraulic Modeling Results Page 6 4.3. Hydraulic Capacity Evaluation MWH performed a steady-state model simulation with a peak hour demand for the planning year 2035. The water distribution system as evaluated to see how the system performed against the reliability criteria provided in Table 1 above. The node pressure and velocity are color coded according to the reliability criteria and are presented in Figure 1 (attached). As shown in Figure 1, the Boulder water distribution is able to meet Peak Hour demands without causing wide-spread violation of the reliability criteria. There are some locations within the city that show pressures less than 40psi. However the majority of these locations are due to high elevation and are not the result from high headloss. Velocities greater than 10 feet/second are shown at Betasso WTF and around several other facilities including Maxwell and Kohler. These high velocities however may be more due to the model representation at these facilities rather than true areas of concern. A review of these results on a city wide basis indicate that the Boulder water distribution system does not have significant capacity issues and is able to adequately meet pressure and velocity requirements throughout the city. 4.4. Fire Flow Analysis A fire flow simulation was performed using the 2035 maximum day demands to identify the available fire flow at model nodes throughout the city's system with a minimum allowable residual pressure of 20 psi. The results from the fire flow analysis are provided in Figure 2 (attached). Available fire flow at each model node is color coded with increments of 500 gpm. As shown in Figure 2, the majority of model nodes are able to provide 1500 gpm of available fire flow or greater. Specifically, 98% of the modeled nodes are able to provide 1500 gpm or greater during a fire condition and 22% of the model nodes are able to provide between 2000 and 3000 gpm of fire flow. A histogram of the available fire flow at model nodes is shown in Figure 3. Review of Figure 2 shows that model nodes which are unable to provide 1500 gpm of available fire flow are mainly located on dead end pipes or on small diameter pipes. Page C-6 August 16, 2010 Hydraulic Modeling Results Page 7 Figure 3 - Available Fire Flow at Model Nodes Maximum Day Demands with 20psi Residual Pressure 25.00% 22% ■ 0 20.00% ■ 500 ■ 1000 m f°- 15.00% ■ 1500 t ■ 2000 c v 10.00% ■ 2500 v a 5%5%5%5%5%5%5%4%5%4% ° ° ° ■ 3000 5.00% ° 2%3% 4/°4/°4/°3% ° 4% 1%2/0 2/0 ■ 3500 p%0% 05/'0%1% 4000 0.00% - O O O O O O O O O O O O O ■ 4500 00 00 00 00 00 00 00 00 00 00 00 00 > 'L 3 0 h 1 ti0 50 h0 ® 5000 Available Fire Flow 5500 4.5. Additional Pressure Zone Analysis The City of Boulder water distribution system is known to have areas with high system pressure. While the reliability criterion establishes a target pressure range of 40 - 80 psi, areas within the system are known to have pressures that exceed 150 or 160 psi. MWH performed a 7-day EPS with minimum month demands for the planning year 2035 to better understand the extent of high pressures within the city's system. A map showing the system pressures for this simulation are shown in Figure 4. As seen in the figure, system pressures vary from some pressures lower than 40 psi at known high points and other systetn pressures reaching greater than 150 psi. High pressures are present along the boundary between Zones 2 and 3 and again between the Zone 2 and 1 boundary. In addition, high pressure nodes stretch the entire north-south extents of the city. MWH facilitated a discussion during the modeling workshop with city staff to better understand the impact high pressures in the water distribution system are having on system operations and maintenance. The city stated that current all residential customers are required to have pressure reducing valves on their water service to bring the pressure down to acceptable levels. In addition, the city stated that the frequency and cost to repair water main breaks is not high enough to justify the previously estimated cost for developing sub-zones to address high pressures. MWH also noted that additional sub-zones could impact the City's ability to transfer water across the system and would likely complicate operations within the water distribution system further. Page C-7 August 16, 2010 Hydraulic Modeling Results Page 8 4.6. Water- Age Analysis A water age analysis was performed using the 30-day EPS model with existing (2010) minimum month and maximum month demands to simulate water age throughout the water distribution system. Water age was used as a surrogate for water quality in this analysis. The city's ultimate goal is to better understand water quality across the water distribution system and identify system operation changes that can be made to improve water quality. The maximum water age from the 30-day EPS is provided in Figure 5 (attached) for the minimum month demand and Figure 6 (attached) for the maximum month demands. A histogram showing water age for the minimum and maximum month demand conditions are shown in Figure 7 and 8 below. i Figure 7 - Water Age 30% Minimum Month Demand Condition 25% 7i 0 20% w 15% c d 10% a 5% 0% O W N lD O -zt W N l0 O-zT M N lD O W N l0 O-zr X N l0 O W N l0 O N'ZT r\ M N'ZT lD M KH RZT LO W. i M l0 W O M In W O N Ln r\ O N E r\ M N ,I ~ H N N N N M M M M ~ ~ ~ -~t M M Ln Ln ~ L.0 I'D t.0 ~O r - Water Age (hours) Figure 8 - Water Age 60% Maximum Month Demand Condition 50% F5 40% Ij 0 F- w 30% - c a U L a 20% - 10% - 0% f 0 48 96 144 192 240 288 336 384 432 480 528 576 624 672 720 Water Age (hours) Page C-8 August 16, 2010 Hydraulic Modeling Results Page 9 As shown in Figures 5 thru 8, water age is greater for the minimum month simulations as compared with the maximum month scenario. Approximately 50% of model nodes in the minimum month scenario have water that is greater than 4 days old. However in the maximum month scenario, only 12% of the model nodes have water age that is greater than 4 days old. For the purpose of this analysis, it is assumed that the minimum month scenario represents a winter condition when temperatures are lower and a maximum month represents a surnmer time condition. Assuming that water quality is affected by temperature, it would be reasonable that higher water ages in the distribution system would be acceptable during the winter months when temperatures are colder. 4.7. System Failure Analysis Five different system failure scenarios were modeled to understand how the City of Boulder could meet demand during a variety of variety of failure conditions. Table 4 previously presented highlights the five failure scenarios modeled as part of the distribution system evaluation. Model results from each scenario were compared against the reliability criteria to determine how well the system was able to meet demand while maintaining level of service under each scenario. Results for each failure scenario are provided in Figures 9 thru 13. In each figure, model nodes are color coded based on pressure and model pipes are color coded based on velocity. The figures are intended to highlight the areas where the reliability criteria are not met. For all system failure scenarios, the city's water distribution system is able to meet the demand condition without dramatically impacting level of service within the distribution system. Failure Scenarios 1, 4 and 5 were simulated for a 7-day EPS run and Failure Scenarios 2 and 3 were simulated for a 30-day period. Figures 9 thru 13 show the pipes with high velocity and nodes with low pressure at the end of the simulation. 5. Recommendations Based on results from the model simulations described in Section 4, the following section provides recommendations for the city's consideration in maintaining and improving the condition and reliability of the city's water distribution system. 5.1. Model Maintenance and Calibration The City of Boulder is a leader among water utilities with their efforts to maintain, modify and use their water distribution system model. Extended period simulations are being perfortned with the use of rule-based controls that mirror the general logic behind the systems manual operation. Based on MWH's review of the model, the results indicate that the model is able to reasonably represent the actual system under normal conditions. However field verified calibration has not occurred for several years and it is unclear how well the model can predict the system's response under a stressed condition. Based on MWH's review of the previous model calibration and discussions during the modeling analysis and workshop with the city, several items are identified as areas for further refinement or development of the model that would enhance the city's use and application of the model. These items are listed below and fall into two general categories. The first category is the improvements to the model to more explicitly represent system components such as valves, hydro facilities and pumps. The second category includes best practices of model maintenance and calibration that are relevant for the city to consider at this time. Page C-9 August 16, 2010 Hydraulic Modeling Results Page 10 Recommendations related to explicit representation of system components: • Addition of pump at Kohler which would represent the backwards flow of water thru the hydropower facility at that location; • Replacement of head versus flow curve at Sunshine Hydro facility instead of the PRV; and • Refinement of roughness factors (c-factors) on the discharge lines from the Betasso WTF to generate the appropriate flow split to Sunshine and Orodell facilities and reduce or eliminate reliance on dummy PRV's to manage flow split. Recommendations for model maintenance and calibration: • Allocation of large users to a separate demand column in the data set; • Refinement of system-wide roughness factors (c-factors) based on loss-of-head tests conducted in the field for a variety of pipe material and sizes; • Field-verified model calibration including pressure monitoring in the distribution system and fire flow tests to test the model's ability to replicate the system's response to a stressed (fire flow) condition; • Temporary system monitoring of pressure in the distribution system and pressure and flow at the discharge points of key facilities; compare these system-wide results to results seen in the model under similar boundary conditions; and • On-going system monitoring program with permanent equipment (pressure, flow, chlorine) to improve real-time operation of the distribution system and increase the city's understanding of the relationship between operating procedures and system conditions (high pressure, water quality). The recommended model maintenance and calibration items could be completed in conjunction with further analysis on the hydraulic capacity and available fire flow as discussed in the sections below. Model calibration activities should be focused on conditions when the system is under stress (peak day or fire flow) or when the city receives information about degraded water quality or increased pressures. The city can also use the model to verify and predict unusual conditions that are often seen during system operations but are not well linked to specific operating procedures. Continued verification and improvement of the model will improve the reliability of the model and the city's use of the model for planning and operations analysis. 5.2. Hydraulic Capacity Evaluation Model results show that the Boulder water distribution system is able to meet peak hour demand conditions without significantly impacting the level of service to customers. No significant bottle necks were identified during the analysis which indicates that the system is relatively robust. MWH recommends the city consider the following items to maintain and improve the system's hydraulic capacity: • Pending verification of roughness and further understanding of the discharge pipelines at Betasso, consider this pipe for further upgrade; • Pending system monitoring program, obtain field data of headloss and velocities at hydro facilities and at tanks to understand actual system conditions at these facilities and evaluate the need to upgrade or replace components; • Upgrade detail at system facilities to better reflect system infrastructure and field verified losses; Page C-10 August 16, 2010 Hydraulic Modeling Results Page 11 • Review and further evaluate the pipes and nodes identified in Figure 1 which violate the reliability criteria; identify incremental system benefit from pipe improvements; • Coordinate with other city agencies to take advantage of roadway or sewer work which may present a opportunity to upgrade pipelines along other construction corridors; • Review model results as part of on-going pipe replacement program to understand hydraulic benefits to pipe replacements; 5.3. Fire Flow Analysis Model results show that 98% of the modeled nodes are able to provide 1500 gpm under a maximum day demand condition. The city should consider additional steps to understand area- specific fire flow requirements and needed system improvements. Specific recommendations include: • Overlay results from fire flow simulation with zoning and land use maps to identify specific areas or properties that would require greater fire flow protection; • Perform additional simulations along Airport Boulevard to establish required system improvements required to provide adequate fire flow to new hotel development in this area; • Conduct field testing such as fire flow tests and loss-of head tests for areas identified with low available fire flow to obtain actual available fire flow and pipeline roughness factor; field testing will allow the city to further understand fire flow restrictions in these areas; • Re-allocation of large users to the most appropriate model node; include large user demand in a separate model database column; identify large-user specific fire flow requirements and document on fire flow map; • Add additional model detail to provide a model node at each fire hydrant location and improve understanding of available fire flow across the system; • Coordinate with planning/pennitting department to establish procedure and documentation needed to document potential system improvements required to provide adequate fire flow for large developments; • Evaluate additional demand scenarios looking at specific industrial areas where demand may increase and result in additional fire flow requirements; and • Leverage on-going flushing program to perform fire flow and loss-of head tests to refine roughness factors. 5.4. Additional Pressure Zone Analysis The City of Boulder water distribution system experiences high pressures along the boundary between the three zones. In addition, the city has reported low pressures along Airport Boulevard and model results show isolated low pressures near Chautauqua. The city continues to evaluate the need for sub-pressure zones. Based on feedback from the city and review of available information, the high pressures in Zone 1 are often due to volunteer fire fighters shutting down hydrants too quickly. Low pressures along Airport Boulevard are due to high elevations (resulting from a slight hill) and because the pipe is undersized. Low pressures also appear to be linked to conditions when the city is pumping from Iris and Cherryvale. However these low pressures along Airport Boulevard are not seen in the model to the extent that they are reported by the city. This is because large users along the Airport Road are not allocated to specific nodes so it is difficult to see the full impact in the model. In addition, low pressures at Chautauqua are not considered by the city to be an issue because there are not customers in this isolated area. Page C-11 August 16, 2010 Hydraulic Modeling Results Page 12 In general, the overall frequency of main breaks in the city's system is within the norm of similar water utilities. In addition, all residential customers have pressure reducing valves and do not experience issues with high pressures in the system. For these reasons, MWH does not recommend that the city move forward with sub-zone development at this time. MWH does recommend that the city follow-up with several tasks that will improve the city's understanding of the relationship between pressure, watermain breaks, and operating procedures. These include the following: • Develop spatial map showing available data on location, frequency, and operating conditions for breaks; • Update demand distribution, specifically focusing on proper assignment of large users; • Develop operations guidelines for fire hydrant exercising and flushing in coordination and discussions with fire department; • Implement system monitoring program including temporary and permanent press loggers to monitor system pressures and track system pressures with system operating conditions; and • Perform additional model simulations to determine if additional pumps at Boulder WTF would help increase pressures in the zone. 5.5. Water Age Analysis Water age analysis can be further advanced with a better understanding of the relationship between water age and water quality. Specifically, the city should consider developing chlorine decay curves to create a relationship between water age and chlorine levels. These curves should be created for each source of supply in addition to curves for various seasons of the year. This information would help the city understand the relationship between water age, water quality and system operation. MWH also recommends that the city install on-line chlorine analyzers at the system tanks to monitor the chlorine levels at these facilities. The city should record the chlorine results with the system operating procedures to determine what correlation there is between operation and water quality. Pending better information from on-line analyzers, the city can consider adding chlorine booster stations or using portable chlorinators to target specific problem areas. The information collected from on-line analyzers and operation set-points would provide insight into the optimum operating conditions and give the city an understanding of what is considered too old water within the City of Boulder's water distribution system. Once the city better understands the impact of system operations on water quality and water main breaks, MWH recommends the city consider creating consistent operating rules which can contribute to more consistent water quality and decreased main breaks. 5.6. System Failure Analysis Simulations were performed for five system failure scenarios identified by the city. Results from all scenarios show that, based on current assumptions and model parameters, the City of Boulder is able to provide adequate flow and pressure during each of these five scenarios. MWH recommends that these scenarios be further evaluated after additional model maintenance and calibration activities are implemented as described above. In addition, PRV settings in the model should be reviewed and updated for specific model scenarios to improve operation of the system and reflect real-time adjustments currently being made by the operations staff. Page C-12 August 16, 2010 Hydraulic Modeling Results Page 13 It should be noted that while the model scenarios show that the Betasso WTF can supply the whole system if the Boulder Reservoir WTF is out of service, the Betasso facility has a treatment capacity limitation, which is currently being studied. The hydraulic model simulation lasted a full seven days; however the known restrictions within the facility would lead to only a few days of maximum output at Betasso before water quality would be diminished. Page C-13 N Figure 1 WV 1E S . t s•. % ti .•Jr ':fie , • e or 1:%j •.•w • . :l 'to r • •t . • •r ! •i i• t .{v. a.• 1. 1*~'•RM1'. r• w, ,too e••••••.• s,.« • I.q•.e! • i .~V• i t. •.1 P-As .20 • I • . • • ' • •i Y A do : • • p ••ti••s •'e.J•! • . % % Legend ~~•i..:J•: •1~.: PRESSURE (PSI) • Less than 10 +M + t • 1020 w ' •J{:r ti • 2030 • 3040 • • 40100 • 100110 • 110120.15 • 120.15140 • 140150 • Greater than 150 VELOCITY (FTIS) Less than 0 0-5 5~7 5-10 Hydraulic Capacity Evaluation Peak Hour Greater than 10 Water Transmission and Distribution System City of Boulder, CO Page C-14 N Figure 2 WV IE S S• : . r t+4 •e'► »e• w • j 1. • O •w• -1. 0• 1 • % • • • • • 41 % Zoo' ~o *1 IL v• .j,; tom. i ~ 1 op 00- • •jeN•• • t• - • .•S•• 0.0 .S :•~•i•.~»••i' i ' ± r-•~-'f-art j ~ • • • t' % 'bU • •~i• ••i ••i •ri t • 7 1 40 o • : •l t t j i• All % :Sitolt• S •i ~ , • • -•st.. • : Ea: ;b .it t Legend Available Flow (gpm) • Less than 500 0 5001000 0 10001500 • 1500-2500 • 2500-3500 • Greater than 3500 Diameter (inches) Less than 6 6-8 8-12 12-48 Fire Flow Analysis Maximum Day + Fire Flow ~ Greater than 48 Water Transmission and Distribution System City of Boulder, CO Page C-15 N Figure 4 WV ,E S ••JIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII IIIIIIIIIIIIIIIIIIIIIII~ c J •a•IYI•Intlltlltlltli•Itlitlltlltl 2 •7i L,; • _....WI■mumlwm■■mwmunnwmulul■nn nu ` ~ I► _ • f i i• • i i : ~ A~IUIIIIIIIIIIIIIIIIIIIIIIII~ aQ • • ! t•. 7•« ~IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII luw 94y oaaa ti • ••I ' ! . ~ • r N ~IIIIIIII 90 4~% ■ • • M... • % i , • t i L T • i rf • • ! • w. • youmnntill nnnm~ 3-s • e- ado°° ~ y!t, ~ i • • • : , t , ~t,••` c~`uuNnunuluuuuunuuny,~' c = 1, '2' i ! ; 2 • • t. 0 or • 91~Ilmmuuuuurr,,~ . . • • ! • i • A i. , • • , ul • .S tit w°~• Legend , PRESSURE (PSI) • • • • Less than 10 s'. • 22 ♦ •Innm~ • 1020 : • • • 2030 g • tt. e m • 3040 2 .(st q • 40100 • • r • a • 100110 • 110120.15 ■nn • 120.15140 • 140150 • Greater than 150 ~~nxnn Pressure Zones yummmne Zone 1 aIIIItlIIIIIIIR ;yItll■I•tlt ~51tl tl a.r Zone 2 ~nmm~ Zone 3 5lnunnfi Diameter (inches) Less than 6 6-8 8-12 12-48 Pressure Zone Analysis Minimum Day ~ Greater than 48 Water Transmission and Distribution System City of Boulder, CO Page C-16 N Figure 5 W E S ttE~ Legend Water Age (hours) • Less than 0 • 0-24 • 2448 • 4896 • 96144 • 144216 Water Age Analysis • Greater than 216 Minimum Month Water Transmission and Distribution System City of Boulder, CO Page C-17 N Figure 6 W E S Legend MAX_QUAL • Less than 0 • 0-24 • 2448 • 4872 • 7296 • 96144 • 144216 Water Age Analysis • Greater than 216 Maximum Month Water Transmission and Distribution System City of Boulder, CO Page C-18 N Figure 9 WV ,E S • ~ • t s•: etc % -SIP .1j.8 v • :t • 1_ •i i' t *0: 7 1M •t • f • : e i'.♦• =•«t.♦.•~ •.•.!i = . .p•.• 3 •••i• '.6 t • • •t• • ° ~ • ~ L • ~ s f it. _ .Sit, 04 % ..••••••••••••.it• A • N .t • e•~ •.0 ! .t • to. • • '1 • •'t i "i % • ♦ i •i Legend •si..:.t•. r PRESSURE ~ ; ' ~.t .it t • Less than 10 t • 1020 'ti • 2030 • 3040 t • 40100 • 100110 • 110120.15 • 120.15140 • 140150 • Greater than 150 HEADLOSS Less than 0 0-5 5-7 5_10 Failure Scenario 1 Greater than 10 Minimum Day Water Transmission and Distribution System City of Boulder, CO Page C-19 N Figure 10 WV ,E S • r • i s•: • •S•• i ti ~ r ~ \ti• r N. • .l;, •h ••:y.:.3~•. • •o•:. i• • • : • • f ' -'M•t••• Its, % •r • •T• 11 'I i• 1 0 16 M •N• • 3 : • • • 'w 1.8 /L4_~ , •=f..i.•.•' 33 ~ •p..~• 3 i'• •M Leh Icy ..•••••.••••••~it• a • N .t p. -0 % .r % _ i Legend •si..:.••. PRESSURE • • ~.t ./t 3 • Less than 10 f: t • 1020 'ti • 2030 • • 3040 t • 40100 • 100110 • 110120.15 • 120.15140 • 140150 • Greater than 150 HEADLOSS Less than 0 0-5 5-7 7_10 Failure Scenario 2 Greater than 10 Maximum Month Water Transmission and Distribution System City of Boulder, CO Page C-20 N Figure 11 WV 1E S r • t s•: etc ti . r ':fie , . ~ . t '•t. i . :••ei'.»•:*1 :'l~i.w'. {.'•3t•. ;.R. • ..l •r.e. '•:i: 00 • t s U. % • • • e • • ~ ~ 1:.'•e ~ ~ ' ` e. •t• •t• • :it'w .tat; • • >r r ' ee„ , • • N y, I A% •r % i _ % Legend •si..:.t•. PRESSURE • ~,t ,/i i • Less than 10 + t • 1020 r'ti • 2030 • • 3040 • • 40100 • 100110 • 110120.15 • 120.15140 • 140150 • Greater than 150 HEADLOSS Less than 0 0-5 5-7 7_10 Failure Scenario 3 Greater than 10 Maximum Month Water Transmission and Distribution System City of Boulder, CO Page C-21 N Figure 12 WV 1E S • r . t s•: Vv W s~ j % N i • • •t • 3• • r e~~•! f • f • • Y M 4 e. r : L • . _ T' . '•I • . • ! , -°'/f.'• . • f i r..• • ~.,f • h 3 • • ~ i ,ice :♦3~.,• - • o• f,34t • . t ~ ' • :'fi't... 4. 4r. r I s•e et. . ~•e,oi'•»•~1 :•f•ri•i..,,~:~w': {.'aft•. ;.P. • ..t •r.e. '..i: i •:••o r•. t• lz:•~t• Lj1 t•rI S' •i A oft .40 mss. t• • t • . • :7~• •.e{ • « /►10.t • 3 , 3:..=•..t.-.•' i3 ~ . 3 •••i. «!.e i'• . imp It. .7 • ; • s: . • , t . • _ . sat , • w • L • 3 i•. •f' I.•ti• • . • e • it • l:ta % :.•i t . i•. • • . i Legend •4i"""••. PRESSURE • • ~.t ./t f • Less than 10 f: t • 1020 {,y•ti • 2030 • • • 3040 ! • 40100 • 100110 • 110120.15 • 120.15140 • 140150 • Greater than 150 HEADLOSS Less than 0 0-5 5-7 7_10 Failure Scenario 4 Greater than 10 Maximum Day Water Transmission and Distribution System City of Boulder, CO Page C-22 N Figure 13 WV ,E S I ° f • t s•: 4 . T ':fie t s nt ~¢s... • •{may 'i ..1 •t• . i•••i'.»•iTt :'1•R•i.w'~L•; it•. ;•R- • .y •r •s. ••=i: 016 . ' tt• * IL .6 7.0 % • • • •~.--w~ • i•f.•=. Nom. • • f w•~ j•••.~. ••ilit •i =f •••1•••••1• • T•r~,t ¢ % r • • • • A • , N , .i •~••••M• • • , • • , t • • • • • so. • „ i % ; . s • 1., ♦ .y ♦ % Legend •ss.:.t•. r PRESSURE ••.fi.:w ; ' ~•t •1s 1 • Less than 10 t • 1020 'ti • 2030 • 3040 ° s • 40100 • 100110 • 110120.15 • 120.15140 • 140150 • Greater than 150 HEADLOSS Less than 0 0-5 5-7 7_10 Failure Scenario 5 Greater than 10 Minimum Day Water Transmission and Distribution System City of Boulder, CO Page C-23 Attachment 1 - Model Calibration Documentation Attachment 2 - Summary of Model Scenarios provided by City of Boulder Page C-24 SYSTEM OPERATING PRINCIPLES System Reservoirs: Zone 1: Gunbarrel Reservoir (2 MG) Zone 2: Kohler Hydroelectric/PRV/Pump Station and Reservoir (9.4 MG) Maxwell Hydroelectric/PRV/Pump Station and Reservoir (9.5 MG) Zone 3: Booton Reservoir (sometimes referred to as North Terminal Tank) (3.5 MG) Chautauqua Reservoir (8 MG) Devil's Thumb Reservoir (5 MG) Intra-zone Connections: Betasso + Zone 3: Orodell Hydroelectric/PRV Station (down 20" pipeline from Betasso) Sunshine Hydroelectric/PRV Station (down 30" pipeline from Betasso) Zone 3 4 2: 101 Pearl PRV Station Kohler Hydroelectric/PRV/Pump Station and Reservoir Maxwell Hydroelectric/PRV/Pump Station and Reservoir Zone 2 + 1: Cherryvale Pump/PRV Station Iris Pump/PRV Station • The distribution system is operated by water treatment operators using SCADA terminals at the Betasso Water Treatment Plant. In general, operation depends on the production at the two water treatment plants and the demands in various zones. Intra-zone connections are used as needed to fill and drain zones and to maintain the level of reservoirs within appropriate ranges. Production from the two plants depends on factors such as system demands and water rights/supplies. Boulder Reservoir WTP is offline more often than Betasso WTP for maintenance, but otherwise it is online year-round. Boulder Reservoir WTP generally provides water to zone 1 and Betasso WTP generally provides water to zones 2 and 3. When reservoirs in the watershed are low, Boulder Reservoir WTP will often treat more water and provide water to zones 1 and 2 so that Betasso water supplies are conserved. When the reservoirs are high, usually in the spring, and start to spill over from snowmelt, Betasso will increase production to treat all the direct flow, so zone 1 can get some Betasso water depending on demands. When demands in the system are high, the watershed manager will decide which plant will increase production based on water rights and supplies. Notes May 2010: In the winter, goal is tank fluctuation. In the summer, goal is overall storage numbers. Summer, both Maxwell and Kohler have flows around 8-12 MGD when Z3 is emptying, and all 3 hydros are on the whole time, and PRVs fluctuate with tank level. 101 Pearl is only used when zone 3 is too full, e.g. when Chaut Tank gets to a certain level. Page C-25 RESERVOIR FLUCTUATION ZONE 2 AND 3 Zone 2 and 3 reservoirs are fluctuated in a targeted manner to promote low water age and good chlorine residual. Fluctuation is accomplished by passing more or less water between Zone 3 and 2. To drain Zone 3 and fill Zone 2, water is moved into Zone 2 through Kohler and Maxwell stations until Zone 3 begins to drain and Zone 2 starts filling. This typically requires the use of the hydroelectric facilities and often the vault bypasses at both stations, depending on seasonal demand and production requirements. In order to fill Zone 3 and drain Zone 2, the flow from Zone 3 to 2 has to be decreased substantially or even stopped altogether. Vault bypasses at Kohler and Maxwell stations are closed and often the hydroelectric facilities must also be shut down. After shutting down the hydroelectric facilities, the stations are put into `pump' mode causing the stations' internal 'Turbine Bypass' valves to close, which stops all flow through the station. Zone 3 reservoirs are not currently fluctuated separately from one another. However, there is a control valves at Booton Reservoir that could be used in a scenario such as keeping Booton level while filling the other two Zone 3 reservoirs, and then opening Booton to increase the filling rate within that tank in order to improve mixing as the reservoir fills. This is not the current practice. ZONE 1 Zone 1, with one relatively small reservoir, fluctuates very easily as part of routine operation. When pumping water west, from Zone 1 into Zone 2, pump speeds cannot be adjusted, and the pumps must occasionally be stopped or started to keep Gunbarrel Reservoir in an appropriate range. When water is flowing east through valves, from Zone 2 into Zone 1, the valves are often opened for long enough to fill Gunbarrel Reservoir and then closed once it is getting full. Through this routine operation of pumps and valves the Gunbarrel Reservoir regularly fills and drains. HYDROELECTRIC OPERATION BETASSO 4 ZONE 3: Sunshine Hydro is typically in operation all year long, except when the station is down for service. This station produces more kilowatts per CFS of water passing through it than Orodell does. Thus, when demand is low during winter months and there is not enough production from Betasso to run both Orodell and Sunshine, Orodell is shut down and winterized. During a normal winter, Orodell will be off for months with just a small amount of water being passed down the pipeline to keep the water fresh. The facility's downstream control valve will be set to pass between 1 to 2 CFS down the Canyon. When Orodell is shut down the Betasso clearwell levels are controlled by adjusting flow through the Sunshine station. ZONE 3 4 ZONE 2: Page C-26 Kohler and Maxwell hydroelectric generators operate anytime water is passing from Zone 3 to Zone 2. At some times of the year, they may be running almost continuously. At other times of the year they may be started and stopped daily. HYDROELECTRIC CAPACITY TESTS: EFFECT ON DISTRIBUTION SYSTEM OPERATIONS Betasso WTP is required by contract to perform monthly Hydroelectric Capacity Tests on the three large raw water hydros: Silver Lake, Lakewood, and Betasso Hydroelectric Stations. On an annual basis a longer duration '4 Hour Capacity Test' is required on these same units. Monthly capacity tests are generally described as either `full bore', `moderate', or `reduced' capacity tests. The amount of generation required and water flows through each hydro is calculated using a complex mathematical equation. This calculation is based largely on monthly power generation figures. Thus the tests are typically run near the end of the month so more complete monthly figures can be used in the calculation. Typically in the winter when hydro generation is low, operators perform a `reduced' capacity test that only requires a kilowatt generation slightly higher than average monthly production. However `reduced' tests are also partly due to problems that have occurred during winter high generation capacity tests. Reduced capacity tests generally require much less special preparation and abnormal distribution operation than higher generation capacity tests. At other times of the year, operators generally have to run much higher volumes of water through Betasso WTP during monthly capacity tests in order to meet generation goals. During the summer, the capacity test often requires the plant to produce 35+ MGD for the duration of the one hour test. These higher flow tests require a much greater amount of advanced planning, strain on the WTP process, and abnormal distribution system operation. SYSTEM PRVS The various pressure reducing valves (PRVs) throughout the system are used as needed based on production at the two plants and overall system demands. There are no pre-set times when they are to be open or closed. SUNSHINE PRV Sunshine Hydroelectric/PRV station has the capability to pass water independent of hydroelectric operation. At times, Sunshine hydro will be running at full kilowatt capacity, and the PRVs will be passing additional water as needed. When the Sunshine hydroelectric generator is off for maintenance, water passes through the PRVs at Sunshine. ORODELL PRV The Orodell Hydroelectric/PRV station also has the capability to pass water independent of hydroelectric operation. However, it has a more limited capacity than Sunshine due to the size of the pipeline and the tendency for vibration to occur if too much water is flowing. The maximum amount of water that can flow through Ordell with both the hydroelectric generator and the generator bypass in operation is approximately 11 CFS, about 8 CFS of which flows through the generator. Above 11 CFS the Orodell station develops a major vibration and cavitation problem. Page C-27 The `Roll-Seal' valve is completely independent of the station. This valve allows additional water to flow around the Orodell station and more water to pass down the 20" Canyon pipeline. The Roll-Seal valve operates on a manually controlled downstream pressure setting. A flow test was conducted in 2008 on the Orodell 20" pipeline, using both the external Roll-Seal valve and Orodell station turbine bypass valve. The 20" canyon pipeline was able to flow approximately 20 CFS. The hydroelectric generator was turned off, the turbine bypass valve was passing about 10 CFS, and the manually operated Roll-Seal valve passed about 10 CFS. 101 PEARL PRV The PRV station at 101 Pearl is primarily used only when a large amount of water has to be moved from Zone 3 to Zone 2. This usually occurs during high demand/production periods in the summer. 101 Pearl is rarely used at any other time since it in essence takes water somewhat directly from Betasso WTP and pushes it into Zone 2, where it is used without greatly impacting the reservoirs in either Zone 3 or 2. Operations have observed that use of this station during low demand periods results in decreasing chlorine residuals in the north and south ends of Zone 3 in particular. However it also seems to have some impacts resulting in increased water age in the north and south ends of Zone 2. This station used to be used more frequently throughout the year. Since changing its operation so that it is primarily used only in high demand situations, there has been a decrease in the number of low chlorine events in both Zone 3 and 2. A general scenario in which 101 Pearl would be used is as follows. Betasso WTP is producing a large volume of water daily, resulting in a need to pass a significant volume of water from Zone 3 to Zone 2. Operators maximize use of the Maxwell and Kohler Hydro stations; first all generators are started to maximize generation before also using PRVs. If additional water needs to be moved into Zone 2 from 3 then operators use the PRV valves at each hydro station first. Often in this situation Kohler and Maxwell stations are each passing 6 to 8+ MGD using the hydros and the PRV bypasses. If high volumes of water are going through both stations but more still needs to be moved, operators begin using 101 Pearl to pass additional water. 101 Pearl is operated using a downstream PSI set point from which the valve automatically regulates to maintain the pressure set point. The pressure set point is increased sufficiently to result in the station passing enough water to obtain the desired results in both Zone 3 and 2. CHERRYVALE AND IRIS PRVs Valves at Cherryvale and Iris are operated as needed when water must be passed from Zone 2 into Zone 1. This occurs either when the 63rd St. plant is not producing enough to meet the demand in Zone 1 or when the 63rd St. plant is offline. Typically the 2" valves are opened first. Then if additional flow is needed the 8" `Main' valves are opened. The main valves operate on a downstream pressure control system. If downstream pressure gets too high they will modulate themselves closed. The Cherryvale main valve has a downstream pressure setting of approximately 65 PSI, and the Iris main valve has a setting of about 55 PSI. These settings are intended to be set low enough such that zone 1 pressures would cause the valves to close before the Gunbarrel Tank overflows. Page C-28 The pumps at Cherryvale and Iris stations are operated in much the same manner as the valves. They are used as needed based on production from 63rd versus Zone 1 demands. If 63rd is producing more water than is needed in Zone 1, pumps are used to move water to Zone 2. The number of pumps used and when they are turned on or off is dependant on production from 63rd and system demands. The pumps are not on variable frequency drives, so they essentially move water at a set rate. Thus they must be cycled on and off as needed. Page C-29 To: MWH Date: May 24, 2010 From: COB Subject: City of Bolder Water Utility Master Plan Model Setup The following steps were taken to prepare the model for delivery to MWH. 1. Update model and demands The model was compared to the current water distribution GIS layer and new pipes imported. I did not have enough time to check for any additional pipes in the model that are no longer in GIS. Based on 2006-2009 ET-adjusted average production of 18,587 acre-feet, base demand is 16.59 MGD. Current and future demands were allocated to all nodes; nodes on 12" and larger pipes and near pumps and valves will be removed for future allocations. The shape file and data from MWH for 2010 usage showed a total usage of 15.7 MGD (this does not include unaccounted for water). After demand allocation in the model, baseline usage for 2010 was 15.6 MGD. The shape file and data from MWH for 2035 usage showed a total usage of 17.7 MGD. After demand allocation in the model, baseline usage for 2035 was 17.6 MGD. There is generally about 8% unaccounted for. We discussed adjusting base demand up by 4% but I left it as is after allocation so MWH can decide final base demand. Note: In order to get correct flow splits from Betasso on the 20" and 30", valve V70008 exists in the model downstream of Sunshine and valve V70010 exists in the model at Orodell. These don't actually exist in the system. Pump and hydro curves may need to be adjusted. Page C-30 2. Update diurnal curve There is no data in the current SCADA software prior to 6/1/06. Data in previous SCADA software is difficult to access and often corrupted. SCADA data from 6/1/06 - 5/12/10 was used to create an updated diurnal curve. Where data were missing, it was estimated when possible from Operators Daily Log entries. Ultimately there were about 1,500 points that had no hourly usage data and 33,120 hourly usage data points. 'Amount Used Over Next Hour' was calculated as: Betasso production that hour + Boulder Reservoir production that hour + difference in total system storage between that hour and the following hour All data were averaged by hour of the day. The average diurnal pattern: Diurnal Pattern Average 2006-2009 21 19 t 17 15 13 0 5 10 15 20 25 Hour of day The average of all hourly data used to create the diurnal pattern is 16.35 MGD, compared to 16.59 MGD from the 2006-2009 ET-adjusted average production. Winter and summer patterns were very different, so 2 diurnal patterns were assigned: Page C-31 2.0 A inter 21•`' -`~ul-~iner ~c u ~ S i~ 2 4 11, 12 14 11; 1z: 20 22 24 HOLIU o Da- Page C-32 3. Operating scenarios 1. MAXDAY_SS. Steady state, max day. PEAKING FACTORS FROM VOLUME II: Between 2000 and 2009: 95th percentile daily factor 2.6. Max day of 43.1 MGD. Peak day factor has not exceeded 2.3 since 2001. However the system has changed since 01 (e.g. Diagonal pipeline) so it may be difficult to compare model results to SCADA data for a day in 2001. SCADA data from the ten days in 2006-2009 with the highest usage was reviewed and 7-24-07 selected to model. Operations suggested 7 am as a time when the system is typically at max usage (which concurs with the diurnal pattern data). The demand multiplier in Infowater was changed to 2.15. Operation on 7-24-07 at 7 am: Max Da SCADA Model 63rd 7.6 m d 7.2 m d Betasso 25.9 m d 25.8 m d Cherr vale 90100 No flow' No flow Iris 90090 No flow No flow Tank level: Boot 12.9 12.9 Tank level: Chaut 18.3 18.3 Tank level: Devils 13.0 13.0 Tank Level: Gunb 9.7 9.7 Tank level: Kohler 14.5 14.5 Tank level: Maxw 16.1 16.1 Hydro 2.9 mgd and PRV at 7.0 Hydro 2.8 mgd and PRV at 7.1 Maxwell 1040, 1007 m d = 9.9 total m d = 9.9 total Both hydros on at 5.6 mgd and Both hydros on at 5.7 mgd and Kohler 1053, 1054 PRV closed PRV closed 101 Pearl 1045 2.6 m d 2.7 m d 20" from Bet 986NET 4.1 m d 4.1 m d 30" from Bet 985NET 21.8 m d 21.7 m d County Jail Press 19452 52.1 psi 55.5 psi Chvl Discharge Press 290 127.5 psi 136.6 psi Chvl Suction Press 54 57.5 psi 61.1 psi Iris Discharge Press 217 121.9 psi 135.8 psi Iris Suction Press 40 48.4 psi 55.9 psi Kohler Z2 Press 778 7.8 psi 9.2 psi Kohler Z3 Press 776 111.3 psi 112.4 psi Maxwell Z2 Press 201 5.0 psi 4.9 psi Maxwell Z3 Press 779 103.2 psi 107.8 psi P101 Down Press 243 65.1 psi 63.1 psi Sun Down Press 527 107.1 psi 108.9 psi Sun Down PRV Press 479 97.9 psi 101.5 psi Sun U Press 470 308.7 psi 324.5 psi ' CV and Iris pumps and PRVs are continuously cycled on and off even on max days. Page C-33 11. Extended Period Simulation, min month Minimum month for 2006-2009 (looking at average use per day) was December 2007: 291,500 gallons for the month and 9.4 MGD average. Set demand multiplier to 0.6. The tank levels and total storage numbers can vary significantly depending on who is operating the system. The model was setup to be as similar to actual December 2007 operation as possible. December 2007 operation: Min Month SCADA Model 63rd 151 1 um on - -3.8 m d Average 3.7 m d Betasso 3214NET 5.6 an d Avera e 5.6 an d Not used as much as Iris, and No flow Cher vale 90100 usual) not at the same time 1 pump on when Gunbarrel at 15 ft On when Gunbarrel at 15 ft and off Iris 90090 and off at 7 ft at 7 ft Tank level: Boot Max 20.7 Min 7.5 Avg 13.4 Max 20.1 Min 8.2 Avg 13.9 Tank level: Chaut Max 21.5 Min 9.6 Avg 14.6 Max 22.4 Min 9.9 Avg 15.7 Tank level: Devils Max 20.8 Min 7.2 Avg 13.3 Max 15.7 Min 3.0 Avg 9.0 Tank Level: Gunb Max 17.1, Min 6.6, Avg 12.2 Max 17, Min 6.6, Avg 11.5 Tank level: Kohler Max 20.3, Min 6.1, Avg 13.0 Max 18.8, Min 6.6, Avg 12.5 Tank level: Maxw Max 18.2, Min 8.1, Avg 12.6 Max 17.0, Min 8.7, Avg 12.5 Hydro on when Maxwell at 9 and Hydro on when Maxwell at 9 and Maxwell 1040 1007 off at 16• PRV closed off at 16• PRV closed Hydros on and off based on Both hydros on when Kohler at 9 Maxwell tank level instead of Kohler 1053 1054 and off at 16• PRV closed Kohler 101 Pearl 1045 No flow No flow 20" from Bet 986NET 0.5 m d 0.5 m d 30" from Bet 985NET 5.1 m d 5.1 m d Sunshine Hydro V70008 Off Off Note: There are new, bigger pumps at Iris and Cherryvale as of spring 2010, which will affect how closely model data matches SCADA data. No pressures were compared. Page C-34 I I I . Steady state, max hour PEAKING FACTORS FROM VOLUME II: Between 2000 and 2009: 99th percentile hourly factor 2.7; max hour of 44.8 MGD. Basically the same as max day operation, just a different peaking factor. Looks like peak hour occurs at 7 am. 7-24-07 7 am, modeled for steady state max day, can be used for max hour scenarios. Amount used in Boulder on 7-24-07 between 7 and 8 am was 44.5 MGD. Page C-35 I V_ Extended Period Simulation, Max month PEAKING FACTORS FROM VOLUME II: Between 2000 and 2009: 95th percentile peak month factor 2.0 Maximum month for 2006-2009 (looking at average use per day) was July 2008: 993,900 gallons for the month and 32.1 MGD average. Set demand multiplier to 2.05. The model is set u with a typi summer operation as follows: Max Month Typical O eration from SCADA Model 63'd 151 2 pumps on - -8 an d Average 8.2 an d Betasso 3214NET Remaining production -24.1 MGD Average 23.9 m d 1 (new) pump on and off based on On when Gunb > 15 and off when Cher vale 90100 Gunb tank level < 9 Iris 90090 No flow No flow Initial level -9. Max 20.7, min Initial level -9. Max 18.5, min 4.6, Tank level: Boot 10.8 av 16.5 av 11.6 Initial level -15. Max 20.7, min Initial level -15. Max 24, min 15, Tank level: Chaut 13.6, av 17.1 av 21.8 Initial level -8. Max 12, min 7.9, Initial level -8. Max 13.2, min 4.3, Tank level: Devils av 10 av 9.6 Initial level -11. Max 18.5, min Initial level -11. Max 18.9, min Tank Level: Gunb 7. 1, av 12.7 8.3, av 13.4 Initial level -17. Max 19.9, min Initial level -17. Max 17.4, min Tank level: Kohler 7.1, av 15.4 7.9, av 12.8 Initial level -17. Max 19.3, min Initial level -17. Max 18.2, min Tank level: Maxw 8.5 av 15.3 8.5 av 13.6 Maxw hydro on; PRV setting 23 Flow varies from 2.9 mgd to 10.3 Maxwell (1040, 1007 or when Maxw level < 8 and setting 5 mgd 1047 90000 when Maxw level > 18. Kohler hydros on; PRV setting it Flow varies from 5.5 mgd to 12.4 Kohler (1053, 1054, V1051, when Kohl level < 8 and setting 6 mgd 90130 when Kohl level > 17 Setting 65 when Chaut level > 17 Flow varies from 0 to 4.5 mgd 101 Pearl 1045 and closed when Chaut level < 17 20" from Bet 986NET -6 m d Average 6.1 m d 30" from Bet 985NET Remaining Bet flow - 18 m d Average 17.8 m d Sunshine Hydro On On Note: There are new, bigger pumps at Iris and Cherryvale as of spring 2010, which will affect how closely model data matches SCADA data. No pressures were compared. Note: This scenario is still being tweaked to get tank levels to match more closely. Page C-36 To: MWH Date: From: COB Subject: City of Bolder Water Utility Master Plan Changes to Model Setup since May 25, 2010 delivery Operating scenarios Note: The Steady State, Max day scenario had the wrong pump curves at Cherryvale; those have been adjusted. The Extended Period Simulation, Max month scenario was adjusted. July 2008 demand average (from Water Treatment demand spreadsheets) was 32.1 MGD and the Infowater demand multiplier remained at 2.05. Actual July 2008 production average according to SCADA data was 30.9 MGD. For much of July 2008 there was only 1 pump on at 63rd so comparison between SCADA to model results is very loose. I could not get tank levels to match any closer with SCADA data. The model is set u with a typi summer operation as follows: Max Month Typical O eration from SCADA Model At 32.1 MGD, there would likely be Average 7.2 mgd 63rd 151 2 pumps on at 63rd - -7-8 m d. At 32.1 MGD, there would likely be Average 24.9 mgd Betasso 3214NET -24.1-25.1 MGD at Betasso. 1 (new) pump on and off based on 1 pump on when Gunb > 16 and Cher vale 90100 Gunb tank level off when < 9 Iris 90090 No flow No flow Initial level -13.3. Max 20.1, min Initial level -13.3. Max 19.4, min Tank level: Boot 10.5 av 16.2 7.4 av 14.1 Initial level -15.9. Max 20.9, min Initial level -15.9. Max 22.2, min Tank level: Chaut 12.6, av 16.8 15.9, av 19.5 Initial level -10.5. Max 12.1, min Initial level -10.5. Max 10.5, min Tank level: Devils 7.4 av 9.8 4.8 av 7.7 Initial level -8.8. Max 17.4, min Initial level -8.8. Max 16.9, min Tank Level: Gunb 6.7, av 12.8 7.4, av 12.2 Initial level -14. Max 19.9, min Initial level -14. Max 15.9, min Tank level: Kohler 7.1 av 14.7 10.8 av 14.1 Initial level -17. Max 19.1, min Initial level -17. Max 17, min 7.3, Tank level: Maxw 8.5, av 15.0 av 12.1 Maxw hydro on; total plant flow PRV setting 20 when Booton level varies from 2.4 (but usu. not lower > 19 and setting 1 when Booton Maxwell (1040, 1007 or than 4.8) to 11.4, average 8.4 level < S. Flow varies from 2.9 1047 90000 would be higher here m d to 9.7 m d av 5.6 Kohler hydros on; total plant flow PRV setting 10 when Booton level Kohler (1053, 1054, V1051, varies from 2.8 MGD (but usu. not > 19 and setting 1 when Booton 90130 lower than 5.5 to 8.8 MGD. level < 8. Flow varies from 5.6 Page C-37 average 6. would be hi her here m d to 10.1 m d, av 6.7 Varies from 0 to 3.2, average 0.9. One valve open at setting 80 for 101 Pearl (V1045, V1023, (would be much higher here entire simulation. Flow varies from 90260 because higher flow from Bet. 5.3 to 6.9 m d 20" from Bet 986NET -6 m d Average 5.2 m d 30" from Bet 985NET Remaining Bet flow - 18 m d Average 19.7 m d Sunshine Hydro On On Note: There are new, bigger pumps at Iris and Cherryvale as of spring 2010, which will affect how closely model data matches SCADA data. No pressures were compared. Page C-38 IDSE Report for a Modeling SSS Page 1 of 11 1. GENERAL INFORMATION Sections or fields marked with an * are required A. PWS Information* B. Date Submitted* Dec 29, 2008 PWS ID 000107152 PWS Name BOULDER CITY OF PWS Address 1094 BETASSO RD State: Colorado Zip/Postal Code: 80302 City BOULDER Population Served 168,000 Enter numbers only System Type CWS Source Water Type Surface/GWUDI Buy/Sell Wholesale C. PWS Operations Residual Disinfectant Type: (x Chlorine F_ Chloramines F_ Other Number of Disinfected Surface 4 GWUDI Ground Purchased Sources: D. Contact Person* Contact Name: KEN CLARK Title: REGULATORY COMPLIANCE SPECIALIST Phone : (303) 413-7404 Ext. Fax: (303) 530-1137 E-mail: clarkke@bouldercolorado.gov II. SSS AND STAGE 2 DBPR REQUIREMENTS* A. Number of Required Stage 2 DBPR Compliance Monitoring Sites: 8 Total 3 Highest TTHM 3 Highest HAA5 2 Stage 1 DBPR B. IDSE Schedule C. Stage 2 DBPR Compliance Monitoring Frequency Select Schedule _71 Schedule 1 During peak historical month (1 monitoring period) Every 90 days (4 monitoring periods) D. Number of Required SSS Samples Page C-39 Total IDSE Report for a Modeling SSS Page 2of11 III. MODELING INFORMATION Skip this section ifyou submitted a modeling study plan with an approved model calibration and your information has not changed, or if you are submitting your plan and report at the same time. A. How was demand data assigned to the model? (attach additional sheets if needed) 1. What method was used to assign demands The utility billing data for metered usage was distributed by throughout the system? address in the city's GIS system. Then a proximity routine was run to assign the usage to the closest pipe, excluding the pipes larger than 12 inches in diameter, and then split the usage between the nodes on either end of the pipe. 2. How did you estimate diurnal demand Diurnal demand patterns for each pressure zone were calculated variation? How did you determine total system using a flow balance into and out of each pressure zone using demand? SCADA data. Total system demand was calculated based on water production records from the water treatment plants and the change in total system storage. 3. How many demand categories did you use? 3 - one for each zone. Each zone has a different percentage of residential, industrial, and commercial users and a different diurnal demand curve. 4. How did you address large water users? Only the meter data was used; this captured all classes of users and demand categories in a single process. By using the meter data we were able to accurately assess the average water use. The city of Boulder has limited industrial users and few, less than 10, with high water demands (there are 6 users total with 8" meters; all others have 6" meters or less). It was not necessary to adjust specific user demand curves to make modeled tank levels match SCADA tank levels. B. Describe all calibration activites undertaken* (attach additional sheets if needed) 1. When was the model last calibrated? September 2007 to match actual conditions in June 2006 2. What types of data were used in the SCADA readings for tank levels, pump flows, and system wide calibration? pressures were collected on 15 minute intervals. 3. When was the calibration data collected? June 2006 from meter data and SCADA data 4. What field tests have been performed to No field tests were performed. collect calibration data? Page C-40 IDSE Report for a Modeling SSS Page 3of11 III. MODELING INFORMATION (Continued) 5. How did you determine friction factors Friction factors were carried over from our previous model into (C-factors)? the new model for the large (10" and larger) diameter pipes. Small diameter pipes added to create the full pipe model had C-factors assigned based upon age and material. CIP, DIP, and PVC have different friction factors in the model. 6. Was the calibration completed for the peak Yes - the calibration was completed for the peak month of June month for TTHM formation? If not, was the and verified using SCADA data for tank levels in June 2006. model performance verified for the peak month for TTHM formation? 7. How well do actual tank levels correlate with The June 2006 actual tank levels are predicted well by the predicted tank levels during the peak month for model. All tank levels are within 11% and 1.3 feet of SCADA TTHM formation? values except for one small tank which varies as much as 19% and 2.6 feet, but it begins to self-correct at the end of the 24 Submit a graph of predicted tank levels vs. hours. See attached graphs (Report Attachment pp.1 &2). measured tank levels for the storage facility with Gunbarrel tank (Z1) has the oldest water age in Zone 1, the highest water age in each pressure zone.* Maxwell (Z2N) in Zone 2, and Chautauqua (Z3M) in Zone 3. 8. If you are using a water quality model, what N/A - we are only modeling water age. parameters are modeled? How was the model calibrated? Page C-4 I IDSE Report for a Modeling SSS Page 4of11 III. MODELING INFORMATION (Continued) C. How was the SSS modeling performed?* (attach additional sheets as needed) 1. Was modeling done for the operating conditions Ce Yes C` No during the peak month for TTHM formation?* 2. How were operational controls represented in Logical controls for all pump stations and for all valves in use the model? were set to reflect typical summer operations by using tank level set points. 3. How was water age simulated during the peak The water age simulation was run for 720 hours to ensure full month for TTHM formation (time steps, length of turnover of all tanks and establish repeating stable system simulation, etc)? conditions. Chautauqua Tank (Z3M) had the high average water age. 4. What are the average water age results for your The average water age was determined to be 10-20 hours distribution system? based on the most frequently occurring age in the histogram.The average water age for the final 24 hours is Submit final model output showing 24-hour given in the attached table (Report Attachment pp. 3-19). average residence time throughout the Nodes with zero demand have an age approximately equal to distribution system.* 720 hours and were not considered in the analysis for site selection. The graph of water age at the longest residence Submit graph of water age at the longest residence time storage facility (Chautauqua Tank) is on p. 20 of Report time storage facility in the distribution system Attachment.pdf. showing the prediction for the entire EPS simulation period.* Page C-42 IDSE Report for a Modeling SSS Page 5of11 IV. SSS MONITORING LOCATION SELECTION How were the SSS monitoring locations selected? (attach additional sheets as needed) 1. What model results were used as the basis for The average water age model results from the last 24 hours of selection? the 720 hour simulation were analyzed. Nodes were ranked by age and a histogram of water age ranges was created (see Report Attachment p. 21). 2. What criteria were used in selecting average The average water age was determined to be 10-20 hours based residence time, high TTHM, and high HAAS sites? on the most frequently occurring age in the histogram. The high TTHM and high HAA5 sites were selected with water ages in the range of 33 to 108 hours, which is the oldest 12% of the water ages in the model (excluding zero demand nodes). Sites were selected to ensure geographical representation of the system and include various pressure zones, mixing zones, and extremities of the system. (See table in Report Attachment p. 22) 3. What additional data was used in the analysis, Total Coliform Rule sampling data for chlorine residual was and how was it used? examined for each potential sampling site. High water age locations with measurable residual were selected for high HAA5 sites. High water age locations with lower residual chlorine were selected for high TTHM sites. 4. How did you look at practical considerations like Accessible sampling sites served by the same water main were accessibility of sampling locations? selected as close as possible to the nodes in the model and with equal water age according to the model. 5. How did you verify that your selected sampling Locations were verified using city GIS streets and parcels layers locations corresponded to the selected node in and comparing the addresses to the information in the hydraulic your model? model. Page C-43 IDSE Report for a Modeling SSS Page 6of11 V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS* A. TTHM Results **If you require additional site entry fields, access the 'SSSMReport Section V.A.pdf file located in the Additional Sheets Site ID & Data Type TTHM (mg/L) LRAA Category Stage 1 Site 1 Sample Date 03/10/2008 6/3/08 9/8/08 12/3/07 Sample Result [0.022 0.0505 J0.0432 0.0365 0.0381 Stage 1 Site 2 Sample Date 3/10/08 6/4/08 9/8/08 12/3/07 Sample Result 0.0182 0.0402 0.0408 0.0317 0.0327 Stage 1 Site 3 Sample Date 3/10/08 6/4/08 9/8/08 12/3/07 Sample Result 0.026 0.0389 0.0388 0.0338 0.0344 Stage 1 Site 4 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.034 0.0498 0.0393 0.0417 0.0412 Stage 1 Site 5 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.0412 0.0453 0.046 0.0432 0.0439 Stage 1 Site 6 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.0332 0.0623 0.0466 0.0463 0.0471 Stage 1 Site 7 Sample Date 3/10/08 6/3/08 9/8/08 12/03/07 Sample Result 0.028 0.0443 0.0587 0.0328 0.0410 Stage 1 Site 8 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.0359 0.0495 0.0435 0.0413 0.0426 SSS-1 Sample Date 6/2/08 Entry 1 Sample Result 0.0344 0.0344 SSS-2 Sample Date 6/2/08 Entry 2 Sample Result 0.0384 0.0384 SSS-3 Sample Date F 6/5/08 Average 1 Sample Result 0.0401 EEJ Attach additional sheets as needed for SSS and Stage 1 DBPR results. Page C-44 IDSE Report for a Modeling SSS Page 7of11 V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS* (Continued) B. HAAS Results **If you require additional site entry fields, access the 'SSSMReport Section V.B.pdf' file located in the Additional Sheets Site ID & Data Type HAAS (mg/L) LRAA Category Stage 1 Site 1 Sample Date 03/10/2008 6/3/08 9/8/08 12/3/07 Sample Result 0.0151 0.0321 0.0268 1 ~ 0.0385 E8171- Stage 1 Site 2 Sample Date 3/10/08 6/4/08 9/8/08 12/3/07 Sample Result 0.0148 0.0385 0.0359 0.0346 0.0310 Stage 1 Site 3 Sample Date 3/10/08 6/4/08 9/8/08 12/3/07 Sample Result 0.0214 0.0392 0.0389 0.0376 0.0343 Stage 1 Site 4 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.0197 0.0402 0.0351 0.0274 0.0306 Stage 1 Site 5 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.0242 0.0295 0.0335 0.0287 0.0290 Stage 1 Site 6 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.0186 0.0477 0.0391 0.0341 0.0349 Stage 1 Site 7 Sample Date 3/10/08 6/3/08 9/8/08 12/3/07 Sample Result 0.0232 0.0343 0.050 0.0372 0.0362 Stage 1 Site 8 Sample Date 3/11/08 6/3/08 9/9/08 12/4/07 Sample Result 0.0209 0.0429 0.0347 0.0263 0.0312 SSS-1 Sample Date 6/2/08 Entry 1 Sample Result 0.0248 0.0248 SSS-2 Sample Date F 6/2/08 Entry 2 Sample Result 0.0410 0.0410 SSS-3 Sample Date F 6/5/08 Average 1 Sample Result 0.0278 JF 0EEJ Attach additional sheets as needed for SSS and Stage 1 DBPR results. Page C.-45 IDSE Report for a Modeling SSS Page 8of11 V. SSS AND STAGE 1 DBPR COMPLIANCE MONITORING RESULTS- (Continued) C. Where were your TTHM and HAA5 samples analyzed? In-House Is your in-house laboratory certified? Yes No C: Certified Laboratory Name of certified laboratory: MWH Laboratories D. What method(s) was used to analyze your TTHM and HAA5 samples? TTHM HAA5 F_ EPA 502.2 F_ EPA 552.1 F_ EPA 552.2 F_ EPA 524.2 EPA 551.1 F_ EPA 552.3 (X SM 6251 B FX_ VI. SELECTION OF STAGE 2 DBPR COMPLIANCE MONITORING LOCATIONS Describe the comparison of sampling and modeling results (attach additional sheets as needed): 1. How well did the sampling results correspond to There was significant variation between sampling results the modeling results? and modeling water age results. Please see attached graphs (Report Attachment p. 23). 2. For samples that did not match well with model please see discussion in attachment (Report Attachment pp. results, what follow-up investigations were 24-30). performed? 3. Were additional samples collected? (Include data No additional samples were collected. on table in Section IV) 4. Submit a graph of water age versus time for each The graphs shown (Report Attachment pp. 31-33) are from selected sampling location.* the original model extended period simulation (EPS) run, not the EPS run that was adjusted to more closely match actual system operation. In either scenario, there are often sudden changes in water age at each location due to a tank starting to empty after filling or vice versa, or due to a pump or pressure reducing valve (PRV) station coming on or Page C-46 IDSE Report for a Modeling SSS Page 9of11 VII. JUSTIFICATION OF STAGE 2 DBPR COMPLIANCE MONITORING SITES* Stage2 Compliance Site Type Justification Monitoring Site ID **If you require additional site entry fields, access the 'SSSMReport Section Vll.pdf' file located in the Additional Sheets folder on the CD. Stage 2 Site 1 Highest TTHM SSS-10 High average water age in both modeling scenarios, high TTHM results during monitoring. Located in Zone 3. (Note: SSS-7 was eliminated from further consideration, please see Report Attachment p. 28 for discussion). Stage 2 Site 2 [Highest HAAS SSS-11 Relatively high average water age in both modeling scenarios, high HAA5 results during monitoring. Located in Zone 2. Stage 2 Site 3 Stage 1 DBPR Stage 1 Site 6 Average residence time Stage 1 DBPR site with high HAA5 LRAA, relatively high average water age in adjusted model. Located in Zone 1. Stage 2 Site 4 Highest TTHM SSS-6 Relatively high average water age in original model, high TTHM results during monitoring. Located in Zone 3. Results at this site are explained in detail in the attachment (Report Attachment pp. 26-27). Stage 2 Site 5 Highest TTHM SSS-16 Relatively high average water age in both modeling scenarios, high TTHM results during monitoring. Located in Zone 2. Stage 2 Site 6 Highest HAA5 SSS-8 Relatively high average water age in both modeling scenarios, high HAA5 results during monitoring. Located in Zone 2. Attach additional copies of this sheet if you need more room. Page t-47 IDSE Report for a Modeling SSS Page 10 of 11 VIII. PEAK HISTORICAL MONTH A. Peak Historical Month* JUNE B. Is Your Peak Historical Month the Same as your Peak Month in Your Modeling Study Plan? G Yes C No If no, explain how you selected your new peak historical month (attach additional sheets if needed): IX. PROPOSED STAGE 2 DBPR COMPLIANCE MONITORING SCHEDULE' Caution: If you intent to send a hard copy version of this plan you should not enter period information that expands past the size of the text box on the form. Anything that appears past the right side of the text box will not show upon the printed document. **If you require additional site entry fields, access the 'SSSMReport Section IX.pdf file located in the Additional Sheets folder on the CD. Stage 2 Projected Sampling Date (date or week)i Compliance Monitoring Site ID Period 1 Period 2 Period 3 Period 4 Stage 2 Site 1 F6/2012, wk 1 9/2012, wk 1 12/2012, wk 1 3/2013, wk 1 Stage 2 Site 2 F6/2012, wk 1 201 9/22,W k 1 12/2012, wk 1 3/2013, wk 1 Stage 2 Site 3 F6/2012, wk 1 9/2012, wk 1 12/2012, wk 1 3/2013, wk 1 Stage 2 Site 4 F6/2012, wk 1 9/2012, wk 1 12/2012, wk 1 3/2013, wk 1 1 -1 Stage 2 Site 5 F6/2012, wk 1 9/2012, wk 1 12/2012, wk 1 3/2013, wk 1 Stage 2 Site 6 F6/2012, wk 1 F9/2012, wk 1 12/2012, wk 1 3/2013, wk 1 Stage 2 Site 7 6/2012, wk 1 9/2012, wk 1 12/2012, wk 1 3/2013, wk 1 Stage 2 Site 8 F6/2012, wk 1 9/2012, wk 1 12/2012, wk 1 3/2013, wk 1 F i period= monitoring period. Complete for the number of monitoring periods from Section ll.C. Attach additional copies of this sheet if you need more room. Page C-48 IDSE Report for a Modeling SSS Page 11 of 11 X. DISTRIBUTION SYSTEM SCHEMATIC* Skip this section if you submitted a modeling study plan and your distrbution system schematic was complete and has not changed from your approved modeling plan, or if you are submitting the plan and report at the same time ATTACH a schematic of your distribution system. If your schematic has changed or if you did not show your SSS monitoring locations on the distribution system schematic you submitted with your model study plan (Form 4), you must submit a revised distribution system schematic. XI. ATTACHMENTS Tabular or spreadsheet documentation that your model meets minimum calibration requirements if updated since approved modeling study plan* (Section III). X❑ Additional sheets for explaining model information/results, including required graphs if not submitted as part of an approved modeling study plan* (Section III) Additional sheets for sampling results, if needed (Section V). 0 Additional sheets for selection of Stage 2 DBPR compliance monitoring sites (Section VI). Graph of water age versus time for all Stage 2 DBPR sites selected* (Section VI). Additional sheets for justification of Stage 2 DBPR Compliance Monitoring Sites, if needed (Section VII). REQUIRED if you are a subpart H system serving more than 249,999 people. Additional sheets for explaining how you selected the peak historical month (Section VIII). Additional sheets for proposed compliance monitoring schedule (Section IX). REQUIRED if you are a subpart H system serving more than 249,999 people. Explanation of deviations from approved study plan. XX Distribution system schematic* (Section X). REQUIRED if it has changed from your approved model study plan or if monitoring locations were not shown. Compliance calculation procedures (for Stage 2 Compliance Monitoring Plan). Total Number of Pages in Your Report: 54 Print Form Submit by Email SECTION III.B.7. Submit a graph of predicted tank levels vs. measured tank levels for the storage facility with the highest water age in each pressure zone. Pressure Average Water Age Tank Zone Hours Gunbarrel Z1 1 83.41 Maxwell Z2N 2 35.68 Kohler (Z2S) 2 26 Chautatu ua Z3M 3 174.7 Devils Thumb Z3S 3 110.85 Booton Z3N 3 87.05 Tank GUNBARREL 15 Model Results N N J Scada Data 0 0 d 8 12 16 20 24 Time (hour) Attachment p. I Page C-50 Tank MAXWELL 20 / Model Results N 10 J 5 - - - Scada Data a 0 4 8 12 16 20 24 Time (hour) Tank CHAUTAUQUA 20 Model Results 15 ' 4} } 10 5 Scada Data 0 0 4 8 12 16 20 24 Time (hour) Attachment p. 2 Page C-51 SECTION III.C.4. Submit final model output showing 24-hour average i°esidence time throughout the distribution system. Avg Age - Avg Age - Avg Age - last 24 1 ast 24 last 24 ID hours ID hours ID hours J10666 108.0 A 1764 29.8 J10490 14.5 J1278 92.0 J10262 29.8 J4822 14.5 J1306 90.9 J10980 29.8 J1168 14.5 J2248 86.4 A 1600 29.8 J7258 14.5 J274 84.8 J7148 29.8 J1648 14.4 J1276 84.5 J11032 29.8 J2192 14.4 J2250 80.9 J5616 29.8 J7236 14.4 J2268 79.8 J3226 29.8 J2478 14.4 J2264 79.8 J11046 29.8 J1620 14.3 J2254 79.5 J5606 29.8 J5024 14.3 J2262 79.4 J3224 29.8 J1228 14.3 J2256 78.6 J3228 29.7 J1190 14.3 J1314 77.9 J5604 29.7 J4992 14.2 J6244 76.1 J11592 29.7 J1020 14.2 J2270 74.4 J11802 29.7 J4996 14.2 J1268 74.1 J3298 29.6 J4798 14.2 J6274 73.0 J5322 29.6 A 178 14.2 J2272 72.2 J7054 29.6 J7218 14.1 J6272 72.0 J10974 29.5 J630 14.1 J272 71.9 A 132 29.5 J1652 14.1 J802 71.5 J5264 29.5 J1350 14.1 J770 71.1 J7548 29.4 J638 14.1 J2276 70.8 J5082 29.4 J1622 14.1 J874 69.8 J7986 29.4 J5938 14.1 J312 68.9 J3302 29.4 J16 14.1 J768 67.7 J3110 29.4 J8406 14.1 J1868 67.3 J862 29.4 J1196 14.0 J6284 66.5 J5314 29.3 J1644 14.0 J6260 65.7 J5624 29.3 J1624 14.0 J4876 65.3 J8054 29.3 J8252 14.0 J1150 64.9 J4556 29.3 J5026 14.0 J6354 642 J11006 29.3 J3830 14.0 J1144 62.7 J7130 29.3 J8408 14.0 J784 62.5 J5582 29.3 J710 14.0 J6298 62.5 J6300 29.3 J1954 13.9 J512 62.1 J6394 29.3 J8390 13.9 J6254 62.0 A 1002 29.3 J1626 13.9 J6896 62.0 J5272 29.2 J1634 13.9 J6866 61.9 J5614 29.2 J1702 13.9 J6940 61.8 J5268 29.2 J8168 13.9 J1148 61.5 J3230 29.2 J8376 13.8 J6908 61.1 J5298 29.2 J1646 13.8 J6936 60.8 J11008 29.2 J1654 13.8 J6880 60.6 J2002 29.2 J6050 13.8 J6854 60.0 J5680 292 J4794 13.8 Attachment p. 3 Page C-52 J4872 59.8 J6418 29.1 J8194 13.8 J6886 59.5 J9990 29.1 J1458 13.8 J6884 59.1 J5256 29.1 J8240 13.8 J6944 59.1 J6466 29.0 J4818 13.7 J4602 59.0 A 1772 29.0 J8304 13.7 J6918 58.7 J6460 29.0 J8216 13.7 J40010 58.5 J4194 29.0 J5448 13.7 J1864 58.5 J540 29.0 J5510 13.7 J776 58.1 J11012 29.0 J2030 13.7 J6286 58.1 J11058 28.9 J3674 13.7 J6894 58.0 J11004 28.9 J1048 13.7 J4246 57.2 J3856 28.9 J8178 13.6 J6900 57.2 J 10324 28.9 J1632 13.6 J3504 57.1 J11804 28.9 J8254 13.6 J6890 56.8 J5330 28.9 J9722 13.6 J6332 56.8 J7840 28.9 J9456 13.6 J4244 56.7 J5284 28.9 J8210 13.5 J4266 56.5 J7998 28.9 J9290 13.5 J788 56.5 J10284 28.9 J10448 13.5 J7636 56.2 J8486 28.9 J4432 13.4 J6906 56.1 J11064 28.8 J5046 13.4 J6336 55.7 J10982 28.8 J8190 13.4 J1870 55.5 J11048 28.8 J2476 13.4 J6322 55.1 J10994 28.8 J9376 13.4 J6458 54.8 J5304 28.8 J1456 13.4 J282 54.7 J5328 28.8 J9772 13.3 J6334 54.0 J5550 28.8 J2470 13.3 J2596 53.8 J4170 28.8 J10456 13.3 J212 53.8 J4306 28.7 J1636 13.2 J6338 53.6 J3236 28.7 J7204 13.2 J7500 53.5 J11042 28.7 J1090 13.2 J6324 53.3 J4594 28.7 J9384 13.1 J7632 53.2 J5254 28.7 J5216 13.1 J6320 52.7 111010 28.7 J1356 13.1 J732 52.3 J2518 28.7 J4774 13.1 J4272 52.1 J8002 28.6 J8188 13.1 J6874 52.0 111510 28.6 J8224 13.0 J210 51.9 J7766 28.6 J7468 13.0 J4270 51.7 J4312 28.6 J7586 13.0 J6340 51.7 J5104 28.6 J1486 12.9 J6876 51.6 J6414 28.6 J8274 12.9 J6902 51.5 J5228 28.5 J1952 12.9 J7158 51.3 J5234 28.5 J4496 12.9 J248 51.1 J7990 28.5 J9338 12.9 J2528 51.0 J5286 28.5 J8234 12.8 J6348 50.6 J3222 28.5 J1630 12.8 J4382 50.6 J10286 28.5 J1562 12.8 J2504 50.5 J5600 28.4 J11424 12.8 J6904 50.5 J11156 28.4 J 10442 12.7 J6302 50.2 J3306 28.4 J7552 12.7 Attachment p. 4 Page C-53 J228 50.0 J6392 28.4 J6218 12.7 J236 491 J11812 28.3 J1610 12.7 J6948 49.7 J4132 28.3 J7676 12.7 J6920 49.6 J3090 28.3 J8228 12.7 J4236 49.3 J11112 28.3 J5982 12.7 J7584 49.1 J6602 28.3 J2468 12.7 J7576 49.0 J8028 28.3 J3874 12.7 J8082 49.0 J10256 28.3 J8100 12.7 J178 48.8 J5274 28.3 J7598 12.6 J6930 48.7 J8056 28.3 J4824 12.6 J6352 48.7 J5260 28.2 J8086 12.6 J6346 48.4 J692 28.1 J 10474 12.6 J726 48.2 J7772 281 J11484 12.6 J7572 48.1 J5308 28.1 J7250 12.6 J266 47.9 J5532 28.1 J5960 12.5 J4226 47.9 J3106 28.1 J9804 12.5 J542 47.9 J896 28.1 J8152 12.5 J7574 47.6 J894 28.0 J9382 12.5 J7692 47.3 J694 28.0 J9266 12.5 J2614 47.1 J9634 28.0 J9346 12.5 J6344 47.0 J11072 28.0 J5034 12.5 J2696 47.0 J4004 28.0 J9764 12.4 J174 46.9 J11808 28.0 J2466 12.4 J7694 46.5 J8008 27.9 J7278 12.4 J7492 46.5 J7176 27.9 J4772 12.4 J6326 46.4 J6382 27.8 J8182 12.4 J156 46.4 J5258 27.8 J8218 12.4 J154 46.4 J2062 27.7 J7530 12.4 J5492 46.1 J7954 27.7 J5484 12.3 J216 467 J5222 27.6 J8186 12.3 J7696 46.0 J7652 27.6 J7528 12.3 J2622 46.0 J3334 27.5 J4782 12.3 J4348 46.0 J6470 27.4 J4958 12.3 J4328 45.9 J6406 27.4 J4430 12.3 J4360 45.9 J4130 27.4 J9454 12.3 J6316 45.8 J5192 27.4 J5840 12.2 J6360 45.8 J4006 27.3 J4720 12.2 J7536 45.7 J3280 27.3 J9286 12.1 J214 45.7 J4220 27.3 J626 12.1 J7154 45.7 J3284 27.3 J5954 12.1 J970 45.7 J526 27.3 J4770 12.1 J3046 45.6 J3970 27.3 J8084 12.1 J6328 45.5 J3728 27.3 J8092 12.1 J10748 45.5 J6390 27.3 A 1498 12.0 J202 45.1 J2044 27.3 J1998 12.0 J254 45.0 J8140 27.3 J4722 12.0 J206 45.0 J3296 27.3 J5016 12.0 J3030 44.7 J7136 27.3 J9668 12.0 J6968 44.6 J518 27.3 J8718 12.0 J10952 44.6 J3988 27.2 J4800 12.0 Attachment p. 5 Page C-54 J2904 44.6 J5184 27.1 J9754 12.0 J188 44.5 J5208 27.0 J4834 11.9 J38 44.4 J3290 27.0 J4970 11.9 J7568 44.3 A 1054 27.0 J5388 11.9 J6868 44.3 J3294 27.0 J7672 11.8 J3004 44.2 J3292 27.0 J1358 11.8 J8076 44.2 J7666 27.0 J6550 11.8 J4278 44.1 J7956 27.0 J4942 11.7 J10744 44.1 J4408 26.9 J6790 11.7 J6958 44.0 J4106 26.9 J3718 11.7 J4372 43.9 J10 26.8 J5832 11.7 J264 43.9 J10098 26.7 J7210 11.6 J4354 43.8 J10070 26.7 J6622 11.6 J4506 43.8 J2472 26.7 J6624 11.6 J4352 43.7 J7976 26.7 J9342 11.6 J3656 43.6 J4516 26.6 J7206 11.6 J3080 43.6 J7978 26.6 J9802 11.5 J6476 43.6 J736 26.5 J5002 11.5 J10738 43.6 J4206 26.5 J5028 11.5 J6942 43.5 J7028 26.5 J9458 11.4 J3940 43.4 J9596 26.5 J4784 11.4 J36 43.4 J4010 26.5 J5030 11.4 J4374 43.3 J4002 26.4 J9698 11.4 J4330 43.3 J5206 26.4 J4716 11.4 J7650 43.3 J4008 26.4 J4964 11.4 J224 43.2 J4078 26.4 J9436 11.4 J32 43.2 J3984 26.3 J4792 11.4 J2652 43.1 J6404 26.3 J7214 11.4 J286 43.1 J8448 26.3 J5910 11.4 J5490 43.1 J4514 26.2 J4764 11.3 J4350 42.9 J3980 26.2 J5450 11.3 J 10372 42.6 J10160 26.2 J8112 11.3 J66 42.6 J3968 26.1 J8116 11.2 J3026 42.3 J6368 26.1 J3458 11.2 J70 42.2 J3326 26.1 J4806 11.2 J8078 42.2 J4478 26.1 J4768 11.2 J10780 42.1 J10066 26.1 J11488 11.2 J7562 42.1 J5182 26.1 J4960 11.2 J3902 42.1 J3986 26.1 J8114 11.2 J7540 42.1 J4138 26.0 J9814 11.2 J972 42.0 J10124 26.0 J4816 11.1 J7504 42.0 J7026 26.0 J8716 11.1 J7490 41.9 J2584 25.9 J2282 11.1 J4202 41.9 J2084 25.9 J9396 11.1 J4456 41.8 J10044 25.9 J9810 11.1 J290 41.8 J4882 25.8 J5070 11.0 J10170 41.7 J4848 25.8 J5010 11.0 J10928 41.7 J7670 25.7 J4962 11.0 J2896 41.7 J4126 25.6 J9372 11.0 J204 41.6 J3426 25.6 J252 11.0 Attachment p. 6 Page C-55 J7544 41.6 J846 25.6 J4696 10.9 J170 41.6 J8804 25.6 J4522 10.9 J764 41.6 J7960 25.6 J9370 10.9 J2952 41.5 J3954 25.6 J9340 10.9 J4324 41.5 J10244 25.4 J4922 10.9 J4332 41.4 J1296 25.4 J4814 10.9 J1908 41.4 J4558 25.4 J5400 10.8 J4504 41.4 J3994 25.4 J6032 10.8 J3882 41.4 A 1238 25.3 J368 10.8 J6350 41.3 J7958 25.3 J6030 10.8 J 10402 41.3 J7846 25.3 J1712 10.7 J7502 41.2 J2100 25.3 J3676 10.7 J10926 41.0 J7032 25.3 J10366 10.7 J4598 41.0 J7166 25.3 J9336 10.7 J4280 41.0 J4146 25.3 J10364 10.7 J2950 41.0 J7686 25.3 J6578 10.6 J10788 40.9 J9588 25.2 J5194 10.6 J3024 40.9 J6416 25.2 J7292 10.6 J11120 40.9 J3866 25.2 J2284 10.6 J2958 40.9 J10072 25.1 J4832 10.6 J4346 40.9 J6436 25.1 J636 10.5 J3054 40.8 J9608 25.1 J4826 10.5 J2944 40.8 J3982 25.1 J4788 10.5 J6478 40.7 J4176 25.0 J9690 10.4 J11088 40.7 J10192 25.0 J4842 10.4 J2956 40.6 J7948 25.0 J4846 10.4 J2440 40.6 J10122 25.0 J7202 10.4 J3042 40.6 J3964 25.0 J10630 10.4 J 10848 40.6 J8844 24.9 J6080 10.4 J10776 40.5 J4198 24.9 J5154 10.3 J6448 40.5 J4178 24.8 J9368 10.3 J6870 40.3 J4108 24.8 J256 103 J1124 40.3 J7134 24.8 J5162 10.3 J6950 40.2 J2526 24.6 J9332 10.3 J690 40.1 J922 24.5 J9330 10.2 J10374 40.1 J6434 24.5 J10618 10.2 J2948 40.0 J4152 24.4 J4930 10.2 J7570 40.0 J7946 24.3 J4810 10.2 J11714 40.0 J4564 24.3 J7296 10.2 J4204 40.0 J10008 24.3 J3832 10.2 J7518 40.0 J7086 24.3 J4492 10.2 J5526 39.9 J816 24.2 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7.4 J128 36.2 J1856 20.2 J6010 7.4 J11702 36.2 J4044 20.2 J5176 7.4 J2928 36.2 J650 20.2 J4668 7.4 J11750 36.2 J 10010 20.2 J5000 7.4 J10414 36.2 J8034 20.2 J491 0 7.3 J7174 36.2 J11154 20.1 J10732 7.3 J680 36.2 J11248 20.1 J6602 7.3 J2404 36.2 J4074 20.1 J4706 7.3 J3104 36.1 J6508 20.1 J5818 7.3 J10396 36.1 J7042 20.0 J4890 7.3 J2934 36.1 J1858 20.0 J11430 7.3 J2708 36.1 J6528 20.0 J5420 7.2 J2802 36.0 J2580 19.9 J11452 7.2 J2962 36.0 J4050 19.9 J5178 7.2 J11674 35.9 J9232 19.9 J6616 7.2 J4316 35.9 J7866 19.9 J7282 7.2 J746 35.9 J9228 19.9 J1088 7.2 J10084 35.9 J4046 19.8 J6812 7.2 J2352 35.9 J7798 19.8 J4616 7.1 J11100 35.9 J4852 19.8 J5970 7.1 J7592 35.9 J8950 19.8 J1006 7.1 J10058 35.8 J8990 19.8 J11380 7.1 J672 35.8 J7868 19.8 J7458 7.1 J11660 35.8 J11236 19.8 J7344 7.0 J2560 35.8 J3356 19.7 J11404 7.0 J3920 35.8 J8872 19.7 J4694 7.0 Attachment p. 11 Page C-60 J10624 35.8 J1534 19.7 J5218 7.0 J7526 351 A 1164 19.7 J6614 7.0 J2524 35.7 J7740 19.7 J6792 7.0 J10090 35.7 J9022 19.6 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J5654 34.0 AE J 10224 34.0 2 18.1 J 5830 5.3 Attachment p. 13 Page C-62 J3074 34.0 J6570 18.1 J11406 5.3 J7984 33.9 J1512 18.0 J5346 5.3 J5670 33.9 J7226 18.0 J3752 5.3 J10652 33.9 J1748 18.0 J5922 5.3 J10674 33.9 J8550 18.0 A 1348 5.3 J2816 33.9 J4512 18.0 J5464 5.2 A 1650 33.9 J9150 18.0 A 1290 5.2 J2782 33.9 J8890 18.0 J6626 5.2 J7488 33.9 J426 18.0 J8146 5.2 J10798 33.9 J8558 17.9 J5348 5.2 J700 33.9 J 10544 17.9 J5914 5.2 J1044 33.9 J9144 17.9 J1370 5.1 J2420 33.9 J8922 17.9 J1096 5.1 J2910 33.8 J8930 17.9 J 11352 5.1 J578 33.8 J6576 17.9 J5134 5.1 J2838 33.8 J9148 17.9 J11374 5.0 J5672 33.8 J10480 17.9 J400 5.0 J11050 33.8 J8858 17.9 J6628 5.0 J11648 317 J1780 17.9 J11478 5.0 J10794 33.7 J8934 17.8 J5698 5.0 J142 33.7 J8258 17.8 J6064 4.9 J4390 33.6 J428 17.8 J5918 4.9 J2818 33.6 J9106 17.8 A 1490 4.9 J10804 33.6 J8560 17.8 J7430 4.9 J5540 33.6 J1756 17.7 J8122 4.9 J6442 33.6 J8784 17.7 J10696 4.8 J10724 33.5 J4026 17.7 J11388 4.8 J2738 33.5 J1764 17.7 J6140 4.8 J2902 33.5 J3570 17.7 J1094 4.8 J3194 33.5 J6504 17.7 J11476 4.8 111518 33.5 J8860 17.7 J7440 4.8 J11686 33.4 J474 17.7 J6046 4.8 J592 33.4 J8410 17.6 J6026 4.8 J2794 33.4 J1770 17.6 J6012 4.8 J10246 33.4 J8526 17.6 J3532 4.8 J1974 33.4 J1740 17.6 J11474 4.7 J3098 33.4 J1726 17.6 J6130 4.7 J11612 33.3 J7588 17.6 J3762 4.7 J934 33.3 J4016 17.6 J8124 4.7 A 1516 33.3 J498 17.6 J6758 4.7 J2400 33.3 J7770 17.6 J11376 4.7 J11684 33.3 J5112 17.6 J11262 4.7 J2574 33.3 J7850 17.6 J3530 4.6 J2800 33.3 J1524 17.5 J10734 4.6 J3218 33.3 J9836 17.5 J11300 4.6 J4596 33.2 J11208 17.5 J2050 4.6 J3068 33.2 J3550 17.5 J376 4.6 J534 33.2 J8480 17.5 J7464 4.6 J568 33.2 J7890 17.5 J 3768 4.6 J2850 33.2 J8494 17.5 J8126 4.5 Attachment p. 14 Page C-63 J2146 33.2 J422 17.5 J5704 4.5 J924 33.2 J8562 17.5 J5438 4.5 J3146 33.2 J8842 17.5 J11398 4.5 J2354 33.1 J450 17.5 J10644 4.5 J10290 33.1 J6536 17.5 A 1382 4.5 J5666 33.1 J8880 17.4 J1362 4.5 J2734 33.1 J4018 17.4 J6020 4.5 J3210 33.1 J7252 17.4 J11396 4.4 J10222 33.1 J1814 17.4 J7424 4.4 J2544 33.0 J7734 17.4 J3386 4.4 J2840 33.0 J4486 17.4 J1360 4.4 J2606 33.0 J1508 17.3 J5728 4.4 J2422 33.0 J484 17.3 J3534 4.4 J2142 33.0 J8834 17.3 J6076 4.4 J5116 33.0 J7754 17.3 J6004 4.3 J10670 33.0 J7764 17.3 J8110 4.3 J2610 32.9 J8498 17.3 J5680 4.3 J4222 32.9 J1526 17.3 J7426 4.3 J2148 32.9 J4020 17.2 J6008 4.3 J3178 32.9 J740 17.2 J1592 4.3 J5658 32.9 J486 17.2 J7422 4.3 J2872 32.9 J8598 17.2 J11446 4.3 J5560 32.9 J7858 17.1 J1384 4.3 J5634 32.9 J1476 17.1 J11358 4.3 J4210 32.9 J482 17.1 A 1304 4.3 J2556 32.9 J3578 17.1 J6024 4.2 J2716 32.9 J11186 17.1 J3384 4.2 J7198 32.8 J4718 17.1 J1418 4.2 J2474 32.8 J478 17.0 J5748 4.2 J2796 32.8 J8838 17.0 J6788 4.2 J5558 32.8 J11166 17.0 J1412 4.1 J1984 32.8 J1272 17.0 J6002 4.0 J5630 32.8 J7244 17.0 J11332 4.0 J7760 32.8 J1828 17.0 J7456 4.0 J5528 32.8 J8850 17.0 J5370 4.0 J3304 32.8 J8830 17.0 J5730 4.0 J10274 32.8 J444 16.9 J11340 4.0 J2004 32.8 J476 16.9 J5682 4.0 J5480 32.7 J4510 16.9 J6066 4.0 J3132 32.7 J8786 16.9 J10694 4.0 J2412 32.7 J1528 16.9 J8098 3.9 J2898 32.7 J8604 16.9 J6816 3.9 J9992 32.7 J4840 16.8 J5372 3.9 J2792 32.7 J8772 16.8 J6070 3.9 J2790 32.7 J2508 16.8 J5920 3.9 J2722 32.7 J1776 16.8 J1400 3.9 J150 32.6 J5950 16.8 J6632 3.9 J2844 32.6 J8796 16.8 J5790 3.8 J2124 32.6 J472 16.8 J1590 3.8 J3944 32.6 N8522 16.8 J 7448 3.8 Attachment p. 15 Page C-64 J10254 32.5 J2510 16.7 J6690 3.8 J2846 32.5 J9830 16.7 J6638 3.8 J10184 32.5 J8782 16.7 J6120 3.8 J2350 32.5 J470 16.7 J10708 3.7 J5294 32.5 J1482 16.6 J5724 3.7 J2396 32.5 J7698 16.6 J8096 3.7 A 1818 32.5 J4498 16.6 J6656 3.7 J4538 32.5 J8574 16.6 J10706 3.7 J3128 32.5 J8794 16.5 J6692 3.7 J2140 32.4 J5946 16.5 J6746 3.7 J10796 32.4 J6074 16.5 J1438 3.7 J2388 32.4 J1774 16.5 J6728 3.7 J5512 32.4 J10516 16.5 J 10642 3.6 J2586 32.4 J440 16.5 J6730 3.6 J144 32.4 J8490 16.5 J374 3.6 J3206 32.3 J1024 16.4 J7434 3.6 J4252 32.3 J4838 16.4 J6694 3.6 J1898 32.3 J8568 16.4 J6096 3.6 J2724 32.3 J4482 16.4 J11254 3.6 J3116 32.3 J1256 16.4 J1572 3.6 J2384 32.2 J11184 16.4 J1064 3.6 J11092 32.2 J8364 16.4 J1566 3.6 J5080 32.2 J468 16.4 J380 3.6 J2870 32.2 J7806 16.4 J6110 3.6 J2848 32.2 J8800 16.3 J6098 3.5 J164 32.2 J5042 16.3 J6122 3.5 J10792 32.2 J8836 16.3 J7414 3.5 J3948 32.1 J1480 16.3 J1568 3.5 J2362 32.1 J430 16.3 J11282 3.5 J2654 32.1 J5102 16.3 J11306 3.5 J5536 32.1 J6506 16.3 J5710 3.4 J2778 32.1 J494 16.3 J1564 3.4 J2554 32.1 J4780 16.2 J6778 3.4 J2446 32.1 J466 16.2 J6104 3.4 J11770 32.1 J8316 16.2 J6770 3.4 J10726 32.1 J1688 16.2 J1556 3.4 A 1090 32.1 J462 16.2 J11256 3.4 J6386 32.0 J8344 16.1 J6128 3.4 J2588 32.0 J5014 16.1 J6086 3.3 J10790 32.0 J8404 16.1 J1640 3.3 J2742 31.9 J8232 16.1 J6108 3.3 J10394 31.9 J7828 16.1 J5732 3.3 J698 31.9 J6544 16.1 J6814 3.3 J10856 31.9 J432 16.0 J6754 3.3 J3130 31.9 J7238 16.0 J6810 3.3 J5476 31.8 J8624 16.0 J1558 3.3 J696 31.8 J8566 16.0 J6084 3.2 J6396 31.8 J9334 16.0 J11360 3.2 J5610 31.7 J7638 16.0 J11268 3.2 J4164 31.7 J1258 16.0 J6088 3.2 Attachment p. 16 Page C-65 J2590 31.7 J8318 16.0 J11284 3.2 J8014 311 J8342 16.0 J5834 3.1 J10220 31.7 J10526 16.0 J6090 3.1 J7612 31.7 J8362 16.0 J6848 3.1 J2572 31.7 J8322 16.0 J378 3.1 J3192 31.6 J8356 15.9 J6092 3.1 J2424 31.6 J7826 15.9 J6784 3.1 J2370 31.6 J8520 15.9 J11258 3.1 J5530 31.6 J5100 15.9 J6114 3.1 J3102 31.6 J442 15.9 J5716 3.0 J5594 31.6 J4484 15.9 J 10640 3.0 J146 31.6 J628 15.8 J 10698 3.0 J4580 31.6 J9936 15.8 J11278 2.9 J5278 31.6 J8802 15.8 J396 2.9 J10378 31.5 J1302 15.8 J11308 2.9 J11096 31.5 J6552 15.8 J11276 2.9 J11098 31.5 J8518 15.7 J1922 2.9 J5608 31.5 J1242 15.7 J6598 2.9 J5592 31.5 J7732 15.7 A 1368 2.9 J5622 31.4 J1208 15.7 J1074 2.9 J3158 31.4 J1754 15.7 A 1326 2.8 J4284 31.4 J8206 15.7 J11312 2.8 J10538 31.4 J9442 15.7 J6138 2.8 J7170 31.4 J8202 15.6 J6780 2.8 A 126 31.4 J5048 15.6 J420 2.8 J5618 31.4 J6486 15.6 J6596 2.8 J10752 31.4 J7646 15.6 J11328 2.8 J4304 31.4 J8576 15.6 J5758 2.8 J148 31.3 J7824 15.6 J11314 2.7 J10228 31.3 J446 15.6 J388 2.7 J2558 31.3 J7656 15.6 J8130 2.7 J4474 31.3 J8250 15.6 J11330 2.7 J5590 31.3 J1050 15.6 J5876 2.7 J2592 31.2 J7738 15.6 J11378 2.7 J5588 31.1 J1696 15.6 J6116 2.7 J152 31.1 J6534 15.6 J1618 2.6 J766 31.1 J4836 15.6 J406 2.6 J2536 31.0 J2578 15.6 J1608 2.6 J2740 31.0 J5004 15.6 J11344 2.6 J10236 31.0 J4454 15.5 A 1342 2.6 J5586 31.0 J8208 15.5 J302 2.6 J3220 31.0 J6492 15.5 J382 2.6 J3724 31.0 J4418 15.5 J6094 2.5 J5542 31.0 J2520 15.5 J11346 2.5 J2540 30.9 J9880 15.5 J5772 2.5 J6400 30.9 J448 15.4 J6126 2.5 J2576 30.9 J2190 15.4 J300 2.4 J2598 30.9 J8340 15.4 J410 2.4 J2454 30.8 J10320 15.3 J6100 2.4 J3112 30.8 J4452 15.3 J5766 2.4 Attachment p. 17 Page C-66 J3174 30.8 J9784 15.3 J5770 2.4 J5312 30.8 J1690 15.3 J6712 2.4 J10742 30.8 J8298 15.3 J6112 2.4 J3150 30.8 J5956 15.3 J5720 2.3 J4576 30.7 J2486 15.3 J11272 2.3 J11124 30.7 J452 15.3 J6170 2.3 A 1060 30.7 J8378 15.3 J6216 2.3 J10068 30.7 J8382 15.3 J408 2.3 J2452 30.7 J8360 15.3 J6210 2.3 J2450 30.7 J8308 15.2 J6230 2.3 J 10248 30.7 J18 15.2 J6786 2.2 J2538 30.7 J8302 15.2 J 10636 2.2 J2374 30.7 J 10422 15.2 J1108 2.2 J5478 30.6 J7208 15.2 J6766 2.2 J7654 30.6 J8392 15.2 J5676 2.2 J7832 30.6 J1220 15.1 J5792 2.2 J8006 30.6 J6620 15.1 J6118 2.2 J7178 30.6 J8780 15.1 J1490 2.1 J3138 30.6 J8792 15.1 J6798 2.1 J7052 30.6 J7222 15.1 J10638 2.0 J3118 30.5 J8388 15.1 J6102 2.0 J5320 30.5 J1614 15.0 J1110 2.0 J6388 30.5 J7736 15.0 J404 2.0 J7664 30.5 J20 15.0 J6738 1.9 J5296 30.5 J1200 15.0 J6124 1.9 J4868 30.4 J8350 15.0 J6154 1.9 J5252 30.4 J8386 15.0 J1772 1.9 J3214 30.3 J 10492 14.9 J6232 1.8 J7702 30.3 J2546 14.9 J1790 1.8 J5302 30.3 J9876 14.9 J6180 1.8 J5548 30.2 J9926 14.9 J6178 1.8 J11080 30.2 J4698 14.9 J6214 1.7 J11056 30.2 J8394 14.9 J5756 1.7 J2312 30.2 J1650 14.9 J6776 1.7 J3144 30.2 J4990 14.8 J1114 1.7 J6424 30.2 J8580 14.8 J1800 1.6 J3216 30.1 J6480 14.8 J1788 1.6 J7988 30.1 J1470 14.8 J6152 1.5 J10740 30.1 J8384 14.8 J6774 1.5 J2758 30.0 J7194 14.8 J6184 1.5 J11768 30.0 J2188 14.8 J1098 1.5 J5280 30.0 J5006 14.7 J6188 1.3 J5318 30.0 J480 14.7 J6174 1.2 J3166 30.0 J8846 14.7 J5856 1.1 J7126 29.9 J646 14.7 J6164 1.1 J3234 29.9 J1472 14.6 J6158 1.0 J4862 29.9 J5842 14.6 J6162 0.9 J6612 29.9 J1664 14.6 J6142 0.8 J1354 29.9 J1222 14.6 477 0.6 J11530 29.9 J10436 14.6 530 0.6 Attachment p. 18 Page C-67 J11040 29.9 J8280 14.6 J6236 0.5 J5250 29.9 J11232 14.6 475 0.4 J4288 29.8 J10452 14.5 472 0.3 J11102 29.8 J8402 14.5 J5900 0.2 471, 0.1 Attachment p. 19 Page C-68 SECTION III.C.4. (contd) Submitgraph of water age at the longest residence time storage facility in the distribution system showing the prediction for the entire EPS simulation period. Tank CHAUTAUQUA 200 150 - ; ; 1 W r i Q} Q Y L r~J 50 i f t 0 120 240 360 400 600 720 Time (hau) Attachment p. 20 Page C-69 SECTION IVA. Histogram of water age ranges. Histogram 700 120.00% 600 100.00% 500 80.00% > 400 U (D 60.00% o Frequency g Cumulative % ii 300 40.00% 200 r 100 20.00% 0 0.00% No yo 30 ~o ~,0 00 AZ' (o C,o & No o ~o ~o )o 00 ~o JQ C§Y ` e hp N N Bin Attachment p. 21 Page C-70 SECTION IV.2. What criteria were used in selecting average residence time, high TTHiW, and high HAA5 sites? Average Water Age Results for SSS Monitoring Locations (Hour 697 to 720 of simulation) Water Age Node hrs Preliminary Category ID J5900 0.20 Entry 1 SSS-1 471 0.12 Entry 2 SSS-2 J6498 20.30 Average 1 SSS-3 J9148 17.91 Average 2 SSS-4 J4962 11.00 Average 3 SSS-5 J7562* 42.09* Average 4 SSS-6 J7158 51.30 High TTHM 1 SSS-7 J2622 45.96 High TTHM 2 SSS-8 J770 71.13 High TTHM 3 SSS-9 J2504 50.48 High TTHM 4 SSS-10 J2374 30.66 High TTHM 5 SSS-11 J282 54.68 High TTHM 6 SSS-12 J2708 36.06 High HAAS 1 SSS-13 J5492 46.12 High HAA5 2 SSS-14 J10154 34.66 High HAA5 3 SSS-15 J2920 37.92 High HAA5 4 SSS-16 This sampling site was inadvertently selected using the wrong model output. Its modeled water age does not fall into the average water age of 10-20 hours. Attachment p. 22 Page C-71 SECTION VIA. How well did the sampling results correspond to the modeling results 2 There are two sets of graphs to represent the samples from each water treatment plant. 63rd TTHMs 0.08 rn 0.07 E 0.06 0.05 0.04 0.03 0 10 20 30 40 50 60 Modeled Water Age (hrs) 63rd HAA5s 0.04 J E 0.035 m m 0.03 v a 0.025 x 0.02 0 10 20 30 40 50 60 Modeled Water Age (hrs) Betasso TTHM 0.07 J E 0.06 YI 0.05 m rY 0.04 0.03 0 10 20 30 40 50 60 70 80 Modeled Water Age (hrs) Betasso HAAS 0.07 m 0.06 E 0.05 y 0.04 h Q Q 0.03 x 0.02 0 10 20 30 40 50 60 70 80 Modeled Water Age (hrs) Attachment p. 23 Page C-72 SECTION VI.2. For samples that did not match well with model results, what follow-up investigations were peiformed? There were some significant differences in controls between the model scenario used to select sample sites and the actual operation of the system at the time of sampling. The most significant was lower actual production at the Boulder Reservoir WTP at 63rd Street (63rd). Controls in the model were adjusted to more accurately represent actual system operation at the time of sampling. Sampling and modeling results correlated more closely after adjusting the controls. 63rd TTHM after adjusting model controls 0.08 RZ = 0.9178 rn 0.07 E Y! 0.06 0.05 0.04 0.03 0 10 20 30 40 50 60 70 Modeled Water Age 63rd HAAS after adjusting model controls 0.04 R2 = 0.9581 E 0.035 y 0.03 m Q 0.025 0.02 0 10 20 30 40 50 60 70 Modeled Water Age Attachment p. 24 Page C-73 Betasso TTHM after adjusting model controls 0.07 R2 = 0.474 E 0.06 N ~ 0.05 = 0.04 0.03 0 20 40 60 80 100 120 Modeled Water Age Betasso HAAS after adjusting model controls 0.07 RZ = 0.5884 rn 0.06 E 49 0.05 N - 0.04 0.03 -r 0.02 0 20 40 60 80 100 120 Modeled Water Age Samples in the distribution system were taken 1-2 days after plant effluent was sampled, and some distribution system DBP results were lower than plant effluent DBP results. This may indicate changing water quality, variations in system operational strategies, or data error. There is a large amount of variation in how the system can be operated, so even after adjusting controls to more closely represent actual conditions, there were still some sample points with TTHM results that did not match closely with the model's water age predictions. SCADA data from the sample collection dates were compared to model data to explain why these points did not match more closely. The first point was SSS-5 (circled in blue on the Betasso TTHM graph above). This sample was collected on June 4. TTHM results at this location were lower than expected, because the model predicted a high water age. This location is downstream of the Betasso WTP, and its water age is most directly affected by Chautauqua Tank (Z3M). If Chautauqua is filling, then the SSS-5 area is being fed by water directly from the Betasso WTP and has a low water age. If Chautauqua is emptying then the SSS-5 area is being fed by water from Chautauqua and has a higher water age. During the last 24 hours of the model simulation, Chautauqua is emptying, so SSS-5 has a high water age. But when the sample was pulled, the tank was actually filling, so SSS-5 was receiving younger water from Betasso. Attachment p. 25 Page C-74 Chautauqua Tank Water Level 5/31/08 - 6/5/08 2a.aao~ ~ a~ 16.6667 Sample pulled 6/4 at 14:10 8.3333 COO 12:01:04 AM 8:01:04 Ph1 4-0114 PM 12:01:04 PM 801:04 AM 4:09:64 AM 12:01:04 AM 5'21!2005 ValR00a 5-1!2008 612+2008 6+3'•2008 614!2008 6!6'2008 his4BWSCADAI.GHAUi_ReSERVCiR LEVEL CHAUTAUQUARESERVOIR LEVEL{FEET}( 975393 FEET 20"6735 95.4873 18,6952 May2008 ir.ey - 'W.-- ' Start Date & Time Chart Duration: Change Time User Functions - Scroll Chart au~eioe'-rue"-wae Tnu Fn sx Days: Hours: Minutes + x• z ~a 2 Hoe Ada Pen I < s s ~r s Is Iro F 2 F- F- 'i11 Ira 19 :ea it 24 Hour Nlete Current Pan _ I URDdtO Chart lu r® an 'si a iii 24 7Day Cv79 FUIISacen ~ Ias ~ .z ita Izs.~ 21 + ar '.a - r ReSe[GtWrt =ay The second point was SSS-6 (circled in green on the Betasso TTHM graph above). This sample was collected on June 3. TTHM results at this location were higher than expected, because the model predicted a low water age. This location is downstream of the Betasso WTP in the city's west pressure zone, zone 3. Its water age is affected by zone 3 tank Booton (Z3N). If Booton is filling, then the SSS-6 area is being fed by water directly from Betasso and has a very low water age. If Booton is emptying then the SSS-6 area is being fed by water from Booton and has a higher water age. During the last 24 hours of the model simulation, Booton is filling so this area has a low water age. When the sample was collected, Booton was also filling. So Booton's level did not explain why the sample results at this point did not match the model prediction. Attachment p. 26 Page C-75 Booton Tank Water Level 5/31/08 - 6/5/08 25.D000-1 16.6647 ILI, Sample pulled 613 at 1-t:4 8.333 0.000- 12;M-.04 AM 8:00:04 PM 4:00:04 PM 12:00,04 PM 100:04 MA 4:00:04 AM 12:00:04 AM 5131I2wa 51'31!2068 $11 2068 612r26C8 6!3!2008 6412046 6/5:2008 hist6WSCADAI.BODTN_RESERVOtR LEVEL BOOTON RESERVOIR LEVEL dFEET) (F CV 12.6566 FEET 15.3905 11.53D7 15,4353 May2008 IMF Start Date & Time Chart Duration: Change Time User_ Functions Scroll Chart San Pen Tw vae Tne RI u Days: Hours: Minutes 2 Hoer ndd ven xi za ~Y.a + a i2 OC J+ OS F_ F_ i -is ,T ~e :v to I tt 2 163 :a n5 t® 'ti 24 Haut Dclcle Current Pen tp i9~'.M T"Zt 123 Sa ODDatE Chan 7 Day GuTO Full Screen ~ J 25 :B '.9 ~1E i4B 9D a s Reset CtMrt 30 Day 1 Even though the line feeding SSS-6 is long, almost 200 feet of 1-inch pipe, this location is a busy strip mall, and the sample was collected from a grocery store. Chlorine residual was relatively high. It is the opinion of city staff that this sample was older than predicted by the model, because there was not much water moving to the Maxwell tank (Z2N) downstream from SSS-6. Maxwell tank had been emptying for almost a day and had been low for several days. When Maxwell tank is not filling, demand in the area is significantly reduced, so the water may have aged in transmission pipes. Another possibility is that a pipe may be missing from the model in this area. A model update is currently in progress by city staff. Without these two points, the TTHM graph now looks like: Attachment p. 27 Page C-76 Betasso TTHM after adjusting model controls, after removing 2 outlying points 0.07 R2 = 0.8052 E 0.06 N N 0.05 01 x 0.04 0.03 0 20 40 60 80 100 120 Modeled Water Age After adjusting the model, the average water age changed from 10-20 hours to 30-40 hours. This may be partly due to the reduced demand multiplier to reflect actual usage at the time of sampling. This also reduced the number of nodes with demand. Water quality in the system can vary widely depending on system operation. Chautauqua tank (Z3M) still had the highest average water age after adjustments to match actual operating conditions. Histogram ofwaterage results afteradjusting model foractual operating conditions 800 120.00% 700 100.00% 600 80.00% 500 U 5 400 60.00% Frequency T Cumulative % LL 300 40.00% 200 20.00% 100 0 - - r-1 0.00% 0 0 8 8 8° 8 8 8 2 ON 8 V S 8° aaa X00 Water Age (hrs) Attachment p. 28 Page C-77 Site SSS-7 was eliminated from further consideration. It is a school and there are access issues in the summer. Also Stage 1 Site 5 is very near to SSS-7 and considered by staff to be more representative of this area. The large difference in TTHM sample results between these two sites is probably due to a recent change in operation of nearby Gunbarrel Tank (Z1) at the time of sampling. Even though there is a large amount of variation in how the system can be operated, city staff agree that this model is a good representation of the system operation, because the model controls generally represent the boundaries of typical summer operation. A few examples are given below: Gunbarrel Tank (Z1) 20 $ 15 .r m 10 5 0 200 400 600 800 Hour Model EPS Results SCADA May-June 2008 Attachment p. 29 Page C-78 Kohler Tank (Z2S) 20 $ 15 m 10 5 0 200 400 600 800 Hour Model EPS Results SCADA May-June 2008 Maxwell Tank (Z2N) 20 15 as 10 5 0 200 400 600 800 Hour Model EPS Results SCADA May-June 2008 Attachment p. 30 Page C-79 SECTION VIA. Submit a graph of water age versus time for each selected sampling location. Stage 2 Site 1 140 120 M 100 m 80 a 60 40 20 0 695 700 705 710 715 720 725 Time (hrs) Water Age Average Water Age Stage 2 Site 2 50 40 L 30 a 20 m r 10 0 695 700 705 710 715 720 725 Time (hrs) Water Age = Average Water Age Attachment p. 31 Page C-80 Stage 2 Site 3 25 rr, 20 t 15 as a 10 m r 5 0 695 700 705 710 715 720 725 Time (hrs) Water Age Average Water Age Stage 2 Site 4 140 120 V! 100 m 80 a 60 40 20 0 695 700 705 710 715 720 725 Time (hrs) -s Water Age Average Water Age Stage 2 Site 5 50 40 L 30 a~ a 20 m r 10 0 695 700 705 710 715 720 725 Time (hrs) Water Age . Average Water Age Attachment p. 32 Page C-81 Stage 2 Site 6 60 N 50 L 40 m 30 20 c~ 10 0 695 700 705 710 715 720 725 Time (hrs) Water Age ~-Average Water Age Stage 2 Site 7 100 Vl 80 t 60 a 40 m r 20 0 695 700 705 710 715 720 725 Time (hrs) -s Water Age Average Water Age Stage 2 Site 8 50 40 L t 30 a~ a 20 m r 10 0 695 700 705 710 715 720 725 Time (hrs) Water Age . Average Water Age Attachment p. 33 Page C-82 SECTION VII. Jitstification of Stage 2 DBPR Compliance Monitoring Sites. Average Average Water Water Age (hrs) Age (hrs) Stage 2 TTHM HAAS - - DBPR SSS LRAA TTHM LRAA HAAS Preliminary Scenario Scenario Selected Sites Results Rank Results Rank Category 1 2 Zone Sites SSS-1 0.0344 22 0.0248 24 Entry 1 0.20 0.20 1 SSS-2 0.0384 18 0.041 7 Entry 2 0.12 0.12 3 SSS-3 0.0401 16 0.0278 23 Average 1 20.30 26.46 1 SSS-4 0.0421 8 0.033 15 Average 2 17.90 38.01 2 SSS-5 0.0379 20 0.0402 9 Average 3 11.00 57.46 3 Stage 2 Site 4: SSS-6 0.0487 3 0.0328 16 Average 4 42.10 5.69 3 TTHM SSS-7 0.0729 1 0.0378 10 High TTHM 1 51.30 63.14 1 Eliminated Stage 2 Site 6: SSS-8 0.0417 9 0.0434 3 High TTHM 2 46.00 41.68 2 HAAS SSS-9 0.0414 11 0.0335 14 High TTHM 3 71.10 17.14 3 Stage 2 Site 1: SSS-10 0.0694 2 0.0629 1 High TTHM 4 50.50 111.81 3 TTHM Stage 2 Site 2: SSS-11 0.0408 15 0.044 2 High TTHM 5 30.7 39.72 2 HAA5 SSS-12 0.0378 21 0.0298 20 High TTHM 6 54.7 38.03 2 SSS-13 0.0414 12 0.0431 4 High HAA5 1 36.10 37.54 2 SSS-14 0.0416 10 0.042 5 High HAA5 2 46.1 41.86 2 Stage 2 Site 8: SSS-15 0.0401 17 0.0403 8 High HAA5 3 34.7 37.70 2 HAA5 Stage 2 Site 5: SSS-16 0.0468 5 0.0413 6 High HAA5 4 37.9 41.07 2 TTHM Stage 1 Site 1 0.0381 19 0.0281 22 Avg res1 14.09 31.15 2 Stage 1 Site 2 0.0327 24 0.031 18 Av res2 34.64 37.45 2 Stage 1 Site 3 0.0344 23 0.0343 13 Av res3 10.42 25.71 3 Stage 1 Site 4 0.0412 13 0.0306 19 Avgres4 30.64 50.39 1 Stage 2 Stage 1 Site 7: Site 5 0.0439 6 0.029 21 Av res5 37.37 46.52 1 Stage 1 Stage 2 Stage 1 Site 3: Site 6 0.0471 4 0.0349 12 Avgres6 15.26 44.47 1 Stage 1 Stage 1 Site 7 0.041 14 0.0362 11 Maxres1 72 17.36 3 Stage 1 Site 8 0.0426 7 0.0312 17 Maxres2 15.2 50.95 1 Attachment p. 34 Page C-83 City of Boulder Final Draft Water Utility Master Plan (February 2011) Page D-1 Appendix D: City of Boulder Utilities Finished Water Energy Dissipation Stations Inspection Report mm" CITY OF BOULDER UTILITIES FINISHED WATER ENERGY DISSIPATION STATIONS INSPECTION REPORT Submitted to: Mr. Robert Harberg Utilities Planning and Project Management Coordinator City of Boulder PO Box 791 Boulder, Colorado 80306 C1 ~ Submitted by: Kevin Clark, P.Eng. MWH AMERICAS, INC. 1801 California St. Suite 2900 Denver, Colorado 80202 Project No. 1008566 August 17, 2010 ID MWH BUILDING A BETTER WORLD Page D-1 MWH BUILDING A BETTER WORLD Overview: Mr. Kevin Clark of MWH Americas, Inc. inspected the City of Boulder (City) Utilities' Energy Dissipation Stations on May 3, 2010 as part of the overall treated water facilities assessment as part of the TWMP. The inspection was to assess the overall condition of the facilities for asset management planning and to identify any major replacement costs that might be required within the next 20 years. The facilities inspected consisted of (in order of inspection): • Orodell Hydro Station • 101 Pearl Street PRV Station • Sunshine Hydro Station and Flow Control Facility • Maxwell Pump Station and Hydroelectric Plant • Kohler Pump Station and Hydroelectric Plant The limited time for inspections only allowed for a preliminary condition assessment based on visual judgment, and did not allow for any in depth inspections. Most of the data collected on the facilities was critically augmented with discussions and input from the City staff present at the inspections. Inspection Date: May 3rd, 2010 Orodell Hydro Station !'i" a~ 4 f r 'Ir L ,k iii. ;a~.9~.ga+.v Photo 1 - Orodell Hydro Building The building was in good to excellent shape (Photo 1) and there was some ongoing construction activity in front of the building related to the pipeline rehabilitation work that the City is having completed on the Orodell Supply penstock pipeline, the Betasso Drain line and the Betasso Hydro supply pipeline. 1801 California St. TEL +1 303 291 2222 Suite 2900 FAx +1 303 291 2221 Denver. Colorado 8020 :v~.vmrnwhglobal.com Eoulderlnapection.Docx Page D-2 `cf'i3 MWH BUILDING A BETTER WORLD 7 -"low, ~Photo 2 - Orodell Hydro System Layout An inspection of the equipment, valving and piping was completed along with the City team, on the inside of the Hydro Building (Photo - 2). Critical initial observations are summarized below in Table 1. Table 1 - Orodell Hydro Component Assessment Equipment Item Comments Turbine/ Generator Good condition - maintenance performed regularly every 5 years (last in 2006) Mfctr: Cornell (Francis turbine) - Only run turbine and generator to 70 kW due to; downstream flow restrictions and cavitation issues; Mfctr: Primeline Generator Turbine Isolation Plug Valve Good Condition - Mfctr: WKM - 12" Bypass Upstream Isolation B'Fly Fair Condition - 12" BFV Valve Bypass PRV Valve Fair Condition - vibration problems at high flow and OH crane does not reach location making service difficult (Mfctr: GAI -12") Bypass Downstream Isolation Poor Condition -12" BFV with broken actuator (locked in open B'Fly Valve position but not a critical valve due to low downstream pressure) Downstream Flow Control Valve Good Condition - operated as turbine discharge control valve due to (Pressure Sustaining) vibration problems by limiting flow with back pressure (Mfctr: CLA- VAL 12" Model 100-20) Miscellaneous Valves and Piping Fair - no major issues reported Battery Back-up and Charging Poor - battery back-up system for I&C is outdated and needs System for I&C replacement. Just completed I&C update (good to very good rating) but the battery system upgrade still required (poor rating) 1801 California St. TEL +1303 291 2222 Suite 2900 FAx +1303 291 2221 Denver. Colorado 8020 w.vw.mwhglobal.com DDL lder Inapection.Docx Page D-3 Papa 3 cf 13 MWH BUILDING A BETTER WORLD Table 1 reflects information compiled from meetings and discussions that were held with City staff subsequent to the original inspection. MWH recommends that a master equipment list be updated for each facility with manufacturer details, date of install, date of last service, maintenance interval and any other special information required (i.e. Overhead Crane does not reach and the preferred method of install/disassembly) for each critical component. References: The following electronic files were provided to MWH by the City and were used as references for the inspection. • 1985-1995-Orodell Hydro As-Built Drawings.pdf • 19637_ 19649_Orodell.pdf • Operation-Maintenance Manual.pdf Orodell Onsite Operating Procedures Manual 101 Pearl Street PRV Station The team then travelled to the Pearl Street PRV location and proceeded with inspection of the critical components. The structure was in very good shape (Photo - 3) with the only item noted being on the outside of the building for potential grading improvement and a gravel or concrete pad for the parking/turn around area- . A r 9 r lx i 1 _ 11 ~ r ~ W+- r.e !r 17 ,r}Y ~ ~ r 9~:.{~1 ~ eC wr ash r -.n yrl.. 1 it rW~A! xy..r a r, ~ v,. Photo - 3: 101 Pearl Street PRV Station Building 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 www.mwhglobal.com boulder InBpection.Docx Page D-4 Page T or` 1 3 MWH BUILDING A BETTER WORLD Initial comments from the inspection of the interior systems (Photo - 4) are summarized in Table 2. t 7 r r. r tt Photo - 4: 101 Pearl Street PRV System Layout Table 2 -101 Pearl Street PRV Component Assessment Equipment Item Comments PRV Valves No. 1 & No. 2 Good condition and no reported problems Isolation B'Fly Valves Good condition and no reported problems I&C System Poor - functioning RTU to be replaced with new fiber optic system and tied into fiber optic hub in the facility The overall condition of the facility was rated as GOOD (Rating = 2). Table 2 also reflects additional information compiled from meetings and discussions that were held with City staff subsequent to the original inspection. MWH recommends that a master equipment list be updated for each facility with manufacturer details, date of install, date of last service, maintenance interval and any other special information required for each critical component. References: The following electronic files were provided to MWH by the City and were used as references for the inspections: Field Drawing w As Built Notoations.pdf • 101 Pearl Pressure Reducing Station Drawings.pdf • Construction Submittals.pdf • Submittals 2.pdf 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 8020 w.vw.mwhglobal.com DDL lder InBpection.Docx Page D-5 Papa 5 cf i MWH BUILDING A BETTER WORLD • SURGE RELIEF VALVES.pdf Sunshine Hydro Station and Flow Control Facility The City and MWH team then proceeded to the Sunshine Hydro Facility location to continue the general inspections. The hydro plant building was in very good shape (Photo - 5) with only some stacked rock retaining wall damage that was noted in the corner of the excavated area (Photo - 6) adjacent to the building. ~F. C, irk R low . •z'+.~. , ~ ~ Pal- "a~ ~ - ~ •iI . a s d p rY' Photo - 5: Sunshine Hydro Building WWI KA `~E tee.'. ° . M R u'wi • .45~~ 1801 California St. TEL +1 303 291 2222 Suite 2900 FAx +1303 291 2221 Denver. Colorado 80202 www.rnwhgloba1.com boulder Inapection.Docx Page D-6 Page 6 of 13 MWH BUILDING A BETTER WORLD Photo - 6: Rock Retaining Wall Damage An inspection of the equipment, valving and piping was completed along with the City team, on the hydroelectric components inside of the Hydro Building (Photo - 7). ilk Ire 4 V~►, 0 Photo - 7: Sunshine Hydro System Layout A list of critical initial observations, are summarized below in Table 3. Table 3 - Sunshine Hydro Component Assessment Equipment Item Comments Turbine/ Generator System Good Condition - Francis Turbine (Hangzhou HL110-WJ-50), Induction Generator (Hitachi new install in 1997) Turbine Isolation Ball Valve Good Condition - Model: 20" Grove B-5 CL300 Discharge Isolation B'Fly Valve Good Condition - 20" BFV Surge Relief Valve Good Condition - Model: 10" CLA-VAL 50A-01 B with no problems reported; condition assumed as rarely actuates Surge Relief Isolation B'Fly Good Condition - 10" Keystone BFV Valves Bypass PRV System and Vault Fair Condition but control issues starting to be noticed in fine tuning pressures/flows; control system and PRV Valves with hydraulic (water) actuated cylinders may need major upgrade in next 5 to 10 years I&C System Good Condition but desire to have RTU interface replaced with fiber 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 8020 w.vw.mwhglobal.com boulder InBpection.Docx Page D-7 Page 7 of 13 MWH BUILDING A BETTER WORLD optic system tied into hub at 101 Pearl Photo - 8 and Photo - 9 show the outside and layout of the Sunshine PRV Vault respectively. •y- .z r. 6. A01 z 34 IA. ika, 4 ;M Photo - 8: Sunshine PRV Vault Opp J~ to ` + I t .,I t. 140, Photo - 9: Sunshine PRV Vault Layout 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 mvw.mwhgloba1.com boulder Inapection.Docx Page D-8 Page 8 of 13 MWH BUILDING A BETTER WORLD The overall condition of the facility was rated as GOOD (Rating = 2). Table 3 also reflects additional information compiled from meetings and discussions that were held with City staff subsequent to the original inspection. MWH recommends that a master equipment list be updated for each facility with manufacturer details, date of install, date of last service, maintenance interval and any other special information required for each critical component. References: The following electronic files were provided to MWH by the City and were used as references for the inspections: • 19830-19848-Sunshine Hydro.pdf • PRV Valve Improvements -Construction Drawings.pdf • Sunshine hydroelectric. pdf • Sunshine Hydro Onsite Operating Manual Maxwell Pump Station and Hydroelectric Plant The City and MWH team then proceeded to the Maxwell Hydro and Pump Facility location to continue the general inspections. The hydro-pump plant building was in good shape (Photo - 10) except for a crack in the CMU block facade at the back corner (covered in more depth by structural inspection as part of Tank/Reservoir task). W~ IC . ! _ r~:lj ~a'.~ t~~~diEr::B~L''.'e1~~ fsry.. '~lc~ Photo - 10: Maxwell Pump Station and Hydro 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 www.mwhglobal.com DDL lder Inapection.Docx Page D-9 Page 9 of 13 MWH BUILDING A BETTER WORLD _LL N, rZ Aj. _ A 7+'°' a Photo 11 - Maxwell Hydro Building CMU Crack - -ate ¢ : r~ _ h IL Z e ~ r Photo 12 - Maxwell Hydro-Pump Layout A list of critical initial observations, are summarized in Table 4. 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 ;vww.mwhglobal.com ooulder Inspection Docr Page D-10 Page 10 of 13 MWH BUILDING A BETTER WORLD Table 4 - Maxwell Pump Station and Hydroelectric Plant Component Assessment Equipment Item Comments Pump - Turbine / Generator Good Condition - Replaced runner with generator rebuild in 2004; System Mfctr: Cornell (Francis Turbine) Pump - Turbine Isolation Valve Good Condition -10" Plug Valve Booster Pump / Motor System Good Condition but rarely used - 8 " pump with 1,500 gpm rated capacity but does not perform to full nameplate capacity Turbine Bypass System Fair Condition - 8" PRV with 8" Isolation BFV's upstream and downstream, only minor maintenance since originally installed, some small leakage from PRV noted from previous maintenance shut- down period Altitude Valve & Reservoir Fair Condition - not specifically inspected but no major issues System reported to team; if major overhaul of valves required no direct overhead access unless remove roof or retrofit other lifting system Meters, Miscellaneous Valves and Fair Condition - not specifically inspected but no major issues Piping incl. Yard reported to team; some deterioration in specific pipe segments due to cavitation and/or site specific corrosion/lining deterioration that was noted from previous dismantling during maintenance (to be confirmed/investigated at next scheduled maintenance period) I&C System Good Condition but desire to have Alan Bradley PLC system installed with programming upgrades The overall condition of the facility was rated as GOOD (Rating = 2). Table 4 also reflects additional information compiled from meetings and discussions that were held with City staff subsequent to the original inspection. MWH recommends that a master equipment list be updated for each facility with manufacturer details, date of install, date of last service, maintenance interval and any other special information required for each critical component. References: The following electronic files were provided to MWH by the City and were used as references for the inspection • 16478-16496 Maxwell pump station & hydro.pdf • Maxwell Pump Station and Hydro Facility O&M Manual-Dec 1985.pdf • 9B14-M-1.PDF • Maxwell & Kohler As-Builts.pdf • Maxwell Onsite Operating Procedures Manual 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Colorado 80202 Nww.nrwhgbbal.corr ooulder Inspection Docr Page D-11 Page 11 of 13 MWH BUILDING A BETTER WORLD Kohler Hydro Station and Flow Control Facility The City and MWH team continued the inspection tour by travelling to the Kohler Hydro and Pump Facility location. The hydro-pump plant building was in very good shape (Photo -13) with no visible issues. Mon 141111111111111W., Photo 13 - Kohler Hydro-Pump Station Layout An inspection of the equipment, valving and piping was completed along with the City team, on the hydroelectric components inside of the Hydro - Pump Building (Photo - 14). it r e w Few, 'y ~ W Photo 14 - Kohler Hydro-Pump System Layout A list of critical initial observations, are summarized in Table 5. 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 :v~.vmrnwhglobal.com ooulder Inspection Dxr Page D-12~age i2 ~f i.', MWH BUILDING A BETTER WORLD Table 5 - Kohler Pump Station and Hydroelectric Plant Component Assessment Equipment Item Comments Pump - Turbine System Good Condition - Replaced turbine runner in Unit 1 in 2004 and new bearing for generator and turbine runner for Unit 2 in 2010 (turbine = Cornell and generator = Marathon XRI) Pump - Turbine Isolation Valves Good Condition - 10 " Eccentric Plug Valve Dezurik Series 118 with fitted Water Cylinder Actuators Turbine Bypass System Good Condition - 10" CLA-VAL Model 10OG Meters, Miscellaneous Valves and Fair Condition - not specifically inspected but no major issues Piping incl. Yard reported to team I&C System Fair Condition but requirement for new PLC (Allen Bradley) as original (Westinghouse) is now severely outdated The overall condition of the facility was rated as FAIR (Rating = 3). Table 5 also reflects additional information compiled from meetings and discussions that were held with City staff subsequent to the original inspection. MWH recommends that a master equipment list be updated for each facility with manufacturer details, date of install, date of last service, maintenance interval and any other special information required for each critical component. References: The following electronic files were provided to MWH by the City and were used as references for the inspection: • 16675-16694 - Kohler Pump + Hydro.pdf • Kohler Equip Submits.pdf • Kohler Equip Submits - Drawings.pdf • 2683626843 - Maxwell Kohler. pdf • Kohler Onsite Operating Procedures Manual 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 v, .vmw hglobal.com ooulder Inspection Docx Page D-13 momomm page (February2411) E_1 Utility of Boulder Final Draft Water Master plan City end►x E' tr~sp ppp nc. L CITY OF BOULDER UTILITIES FINISHED WATER RESERVOIRS INSPECTION REPORT Submitted to: Mr. Robert Harberg Utilities Planning and Project Management Coordinator City of Boulder PO Box 791 Boulder, Colorado 80306 C1 ~ Submitted by: Jed W. Iverson, P.E. MWH AMERICAS, INC. 1801 California St. Suite 2900 Denver, Colorado 80202 Project No. 1008566 August 13, 2010 ID MWH BUILDING A BETTER WORLD Page E-1 MWH BUILDING A BETTER WORLD Overview: Mr. Jed Iverson, P.E. of MWH Americas, Inc. inspected the City of Boulder Utilities' finished water reservoirs on May 3rd and May 4t", 2010. The inspection was to assess the overall condition of the reservoirs for asset management planning and to identify any major replacement costs that might be required within the next 20 years. The City maintains six (6) finished water reservoirs and the inspection of each reservoir will be described below. Because of the nature of the condition assessment, all the inspections were allotted 30 - 45 min each. The limited inspections only allowed for a preliminary condition assessment based on visual judgment, and did not allow for any in depth inspections. Inspection Date: May 3rd, 2010 Reservoir: Maxwell Reservoir The as-builts for Maxwell Reservoir show that the reservoir has a plan dimension of 360 feet x 200 feet with a capacity of 9.5 MG. The reservoir is covered with concrete double tees supported by concrete beams and columns. The double tees are covered with insulation and topped with asphalt and gravel. The perimeter of the reservoir sticks above the finished grade approximately 5 feet and slopes in the shorter dimension up to the center at approximately a 1.5% slope. I started my inspection on the Eastern side of the tank, just above the Hydro building. Approximately 100 feet from the Southeast corner there is a longitudinal crack mid height of the exposed wall. This crack extends approximately 30 - 40 feet and is most likely due to horizontal movement of the roof diaphragm, lateral movement of the base of the wall from external soil pressure, or stem wall settlement from soil erosion. This is an item that should be highlighted as needing attention and should be fixed or at least patched in the near future so freeze thaw cycling does not deteriorate the wall further. r Photo 1 - Maxwell - Longitudinal Crack, Southeast Corner 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Coloredo 80202 w.vw.mwhglobal.com Page E-2 ci MWH BUILDING A BETTER WORLD Continuing along the Eastern wall towards the North, the rest of the wall was in good shape with minor horizontal and vertical cracks. This was also the case for the remainder of the exposed wall segments. The vertical cracks were most likely due to thermal expansion and contraction while the horizontal cracks were most likely due to similar conditions as described in Photo 1. As I continued around the reservoir, one note of concern was where the finished grade was sunken in adjacent to the exposed wall. These areas were approximately 10 feet long and up to 2 feet deep and occurred every 20 to 30 feet along the reservoir perimeter. This could be from the soil settling, the surface water eroding the soil, or from soil piping along a reservoir leak. This will need to be fixed and can be detrimental to the structure by allowing water to freeze close to the base of the footer. This can result in uplift of the wall, settlement of the wall, or can allow external pressure from the ice expanding against the existing soil. See Photo 2 for a sample of the sunken areas. ,&L-- ~y, 1 4W. --=~aA,M.:' j' Ir Xlih k ° ~ yyl, Wr ke,` ~ •C;, fI v! y~ Z7: ~yy5a 1a, r Y _=wv r p 1f " t`•« fcr rg• rs~~~ ~r/1'„+.i i ,Jc~`a~ ~ `'emu is ISI. !h: ~i_~a2. .L. ~I': •.J` ri.«l '.!1 L.11• _ 1... _ t~ . a Photo 2 - Maxwell - Typical Sunken Area Adjacent to Exposed Wall At the corners of the reservoir it was clear that the structure was experiencing some movement. A clear separation of the wall segments was visible and a couple of the corners the construction joint was starting to separate up to a 1/4 of an inch. This appeared to be a true movement joint because felt material was visible in the joint. Photo 3 illustrates this separation and should be at a minimum caulked to prevent moisture penetration. 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Coloredo 80202 1. vww.mwhglobal.com of Page E-3 Page 3 26 MWH BUILDING A BETTER WORLD E .1 Photo 3 - Maxwell - Typical Separation at Corner On the North and South wall midpoint between the East and West walls, there was a movement joint at the base of the exposed wall. This movement joint was 1 1/2 inches wide and was showing signs of soil erosion adjacent to the joint. This joint should be repaired as soon as possible to prevent water penetration. Photo 4 illustrates the condition at each side of the tank. Photo 4 - Maxwell - Typical Midpoint Joint at N/S walls 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Coloredo 80202 ,,o.vw.mwhg1oba1.com Page E-4 MWH BUILDING A BETTER WORLD There is an access entry into the reservoir from the Southwest corner, but the layout of the finished grade around the area should be re-evaluated. The ground slopes toward the entry and seems like there is potential for snow and ice to build up in this area as well as the potential for water to erode and undermine the foundation. The steel enclosure is in good shape, but the coating could use some touch up and the joints should be re-sealed. See Photo 5 for a view of the access from the side. The photo shows one side of the access area and the opposite side is similar to the view shown. sy~ :.~I 'yam,{,~~F r( f r ~ r• r ; y Y~ tot s (r r 1, l 'ff 'k*~ t i ORO" r IL Al 4 Photo 5 - Maxwell - Access Entry at Ground SW Corner 1801 California St. TEL +1303 291 2222 Suite 2900 Fvc +1303 291 2221 Denver. Coloredo 80202 www.mwhglobal.com Page E-5 Page 5 of 26 MWH BUILDING A BETTER WORLD Next, the roof was inspected and the built up asphalt and gravel portion was determined to be past its service life. The tar is visibly cracked and there are numerous soft spots. The soft spots are where water has seeped into the insulation between the concrete double tees and the asphalt. The current design of protecting the concrete double tees with a built up roof is not a recommended practice and lends its self to trapping moisture. This has the potential to corrode the shear tabs of the concrete double tees and can be seen to be already happening at the Chautauqua reservoir. We accessed the tank at the Southwest Corner, but was not able to get good pictures of the double tee shear tabs. It is apparent though that the roof is retaining moisture and eventually the roof diaphragm system will fail if it hasn't already. MWH suggests installing a different roof system, one that will allow the area above the concrete double tees to breathe and still shed water and snow. Photo 6 is a typical example of the condition of the roof. roe Cis / • t.: ~ _ ti . - Photo 6 - Maxwell - Typical Roof Condition Besides the roof, the other items that were inspected were the ladders, vents, and hatches. All were in working condition, but the coating on the vents and hatches will need to be re-coated in the near future. I did go into the reservoir through the Southwest hatch, but did not go past the landing platform. The reservoir was in service at the time of inspection and only part of the lining system was visible. For what I could see, the lining system was intact and in somewhat of a working condition, but I was not able to verify the condition of the lining system. 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Coloredo 80202 w.vw.mwhglobal.com Page E-6 MWH BUILDING A BETTER WORLD Following the inspection of the reservoir, I was asked to quickly look over the Hydro Building adjacent to the reservoir. The Hydro building is a single story CMU building with a concrete slab on grade. In the back of the Hydro building there is a pump area that is a half story lower than the main floor. At this back area, the outside corner is seeing some cracking in the CMU block. It was difficult to determine the cause of the CMU cracking, see Photo 7. When we looked at the same area from the inside, I noticed the wall was concrete. It appears the wall is concrete and the CMU block outside is just a veneer. I could not verify the construction because design drawings were not available for the Hydro building, but the cracking does not seem to be affecting the stability of the building. Further investigation into the cause of the CMU block cracking is needed to determine the right course of action to repair the CMU block. The rest of the building appeared to be in good condition. =1 •~11 `fir#~p Photo 7 - Maxwell - Hydro Building CMU Crack 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Coloredo 80202 www.mwhglobal.com Page E-7 Page 7 of 26 MWH BUILDING A BETTER WORLD Summary: It is difficult to rate the whole structure by performing such a quick inspection of the reservoir, but there are definitely components of the structure that need attention. The following list describes the external items that need attention and should be maintained on a regular basis. • Longitudinal crack close to the Southeast corner of the reservoir should be inspected further for the potential causes of the crack and a repair procedure should be developed before the winter season • Eroded soil areas along the perimeter of the reservoir should be inspected further for the cause of the erosion and a repair procedure should be implemented. Suggest replacing the grass/soil adjacent to the structure with free draining gravel to help with erosion. • Construction and movement joints at the corners and at the midpoint of the North and South walls of the reservoir should be sealed from external weather before the winter season • The layout surrounding the reservoir ground access area should be investigated and a re-grading solution should be developed and implemented. The steel enclosure should be re-coated and the joints re-sealed. The roof at a minimum should be recoated or a new roof system should be developed to minimize trapping moisture against the concrete double tees. • All coated surfaces should be analyzed to determine the current condition is adequate to prevent corrosion for external elements. Form the current visual inspection, there are many areas that need to be re-coated. The CMU Crack at the Hydro building should be inspected further to determine the cause and a repair procedure should be developed and implemented prior to further deterioration. References: The following electronic files were provided to MWH by the City and were used as references for the following inspection 3051-3052 Maxwell Reservoir plan & const..pdf 06515_06516-196 8-BV4196.02. pdf • 06517_06529-BV09C . pdf • Maxwell-Reservoir Property_1966.pdf 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Coloredo 80202 wmAi.mwhglobal.com Page E-8 Page 8 of 26 MWH OVILDING A BETTER WORLD Inspection Date: May 3~d, 2010 Reservoir: Kohler Reservoir The as-builts for Kohler Reservoir show that the reservoir has a plan dimension of 330 feet x 230 feet with a capacity of 9.4 MG. The reservoir is very similar to the Maxwell reservoir but is covered with a metal deck roof supported by metal purlins. At the time of the inspection, I was not able to gain access to the inside of the reservoir, so I was not able to visually determine the condition of the roof structure or the reservoir. The metal roof is galvanized steel that has been coated with what appears to be a latex based paint. The roof was originally fastened to the purlins with hex headed screw fasteners and the paint coating was applied over the fasteners. The roof has two major peaks with a pitch of approximately 6H : 1V. In the middle of the two peaks, the metal deck runs into a metal gutter that carries water to the North and South sides of the reservoir. The reservoir sticks above ground, at the low point, approximately 4 feet with metal decking covering the concrete wall portion that is above grade. Because I was not able to get into the reservoir, the inspection consisted of a visual observation of the condition of the roof, soil adjacent to the structure, and the portion of the concrete exterior wall that was not covered by metal deck. The first area I looked at was the general condition of the roof. The coating on the metal deck has failed and there are large cracks in the paint coating. Photo 8 shows a typical condition of the paint coating and how the screw fasteners have now been exposed to the elements. Further investigation into the condition of the support structure will need to be completed to make a decision on whether to re-coat the metal roof or to replace the system entirely. Photo 8 - Kohler - Typical Roof Coating Condition 1801 California St. TEL +1303 291 2222 Suite 2900 Fax +1303 291 2221 Denver. Coloredo 80202 v.v~w.mUhglobal.com Page E-9 MWH BUILDING A BETTER WORLD At the corners of the reservoir it was apparent that the concrete was experiencing some movement. Below the metal deck paneling at the corners, one could see large gaps up to 1 1/2 inches wide. These areas should be sealed and protected from water penetration. Photo 9 shows one of the worst corners. `~i, Photo 9 - Kohler - Wost Case Corner Condition Besides the corner separation, there was also separation at other movement joints. The separation wasn't as bad as at the corner shown, but was approximately 1 inch wide. Photo 10 shows a typical movement joint. These joints should be sealed as soon as practical to prevent water penetration and the possibility of further damage from freeze thaw conditions. fis aid u° r Zt- I .''1 y yY' ~r F 4 Photo 10 - Kohler - Typical Movement Joint 1801 California St. TEL +1303 291 2222 Suite 2900 -AX +1303 291 2221 Denver. Colorado 80202 ,P.vw.mwhglobal.com .7ULider IlSi;eG'!Ufl. DocX Page E-1 0 Par,U 10 Oi 26 MWH BUILDING A BETTER WORLD In the middle of the two peaks the metal deck terminates at a gutter. The gutter runs the length of the structure and slopes to the exterior. The gutter is also galvanized metal that has been coated in paint, but most of the paint coating has been worn off. At a minimum this gutter should be re-coated and fully inspected to determine if there are any localized areas of corrosion. Photo 11 shows the current condition of the gutter. It was also unclear if the ends of the metal deck were open to the reservoir. If so, this could lead to animals nesting or crawling into the reservoir. It might be necessary to seal the ends with closure strips, but further investigation would be necessary. ~l a Photo 11 - Kohler - Gutter Condition As the roof was being inspected, I was also inspecting the lower portion of the concrete stem wall. For the most part, the portion that was exposed was in good condition with only small hairline cracks. Another item of concern is the vegetation surrounding the reservoir. Almost the entire perimeter had some sort of bush or vegetation growing next to the structure. This was really a problem on the West side where there were even a couple of trees observed to be right next to the reservoir. Photo 12 shows the worst case where trees and bushes are growing adjacent to the concrete stem wall. It is imperative that this vegetation be removed, along with some soil, and replaced with free draining material. There was also evidence of some sink holes and soil erosion 1801 California St. TEL +1303 291 2222 Suite 2900 -AX +1303 291 2221 Denver. Colorado 80202 v, .vmmwhglobal.com ooulder Inspection Dxx Page E-11 - - MWH BUILDING A BETTER WORLD adjacent to the wall. Further investigation into why there are sink holes should be performed and a repair solution should be created and implemented. It's important that the ground slopes away from the structure so that water doesn't further erode the soil around the structure. If too much of the soil erodes, frozen water can act on the footing and cause damage to the supporting concrete wall. I I . e S Y rr t ~r Mi.l -Tlz t~r~lf7S `y~~ 1 i ,f L- ty r r .4 ly8f -41 T ivy A z" Photo 12 - Kohler - Worst Case Vegetation Adjacent to Structure As I walked around the reservoir, there were a couple of minor items that should be maintained on a regular basis. On the East side of the building where the exposed piping enters the reservoir, it was apparent that the piping needs to be re-coated. The existing coating system has failed and is peeling off. There are also localized areas where the vertical paneling around the reservoir has been damaged by vandalism. The metal decking in these areas has been smashed in, but is still intact. This will need to be fixed or at least re-coated, but is a minor issue. I also briefly looked at the Hydro facility to gauge its condition. The building was a single story CMU building with a concrete slab on grade. Both the inside of the building and exterior looked in good shape and does not need maintenance at this time. There were a few small shrinkage cracks in the CMU wall, but nothing of concern. 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 :vww.mwhglobal.com Eoulder Iwpection Docr Page E-12 Page 12 of 26 MWH BUILDING A BETTER WORLD Summary: It is difficult to rate the whole structure by performing such a quick inspection of the reservoir, but there are definitely components of the structure that need attention. The following list describes the external items that need attention and should be maintained on a regular basis. • The roof coating system has failed and should be repaired or the entire roof should be replaced. Further investigation is needed to determine the condition of the metal decking as well as the roof steel support framing members. It might be necessary to replace the entire roof system. • Joints in the concrete walls that have opened up due to wall movements should be sealed and protected from external weather. This is necessary to prevent future erosion problems. • Coating system on the gutter between roofs has failed and the condition of the gutter should be evaluated to determine if it should be replaced or re-coated. • Vegetation around the reservoir should be removed and the top layer of soil replaced with free draining material. The finished grade along the reservoir should also be regarded to allow drainage away from the reservoir. References: The following electronic files were provided to MWH by the City and were used as references for the following inspection 02488-02489-BV9A. pdf 02712-02716-South Storage Reservoir.pdf • 33420-33423 Kohller Reservoir.pdf • KOHLER_RES.pdf • 1 C17-1962-Drawing Kohler Reservoir Easements.pdf 1801 California St. TEL +1303 291 2222 Suite 2900 -AX +1303 291 2221 Denver. Colorado 80202 :vwmrnwhglobal.corn ooulder Inspection Docr Page E-13 Face 13 cf 2u MWH OVILOING A BETTER WORLD Inspection Date: May 4th, 2010 Reservoir: Devils Thumb Reservoir The as-builts for Devils Thumb Reservoir show that the reservoir has a plan dimension radius of 102 feet and a capacity of 5.0 MG. The reservoir is an above grade steel tank that sits on a concrete slab-on-grade with a thickened edge. The tank is roughly 20 feet tall with the roof sloping from the center to the outside edge. Along the perimeter of the tank is a metal rain guard that is approximately 12 feet above the ground and protrudes 1 to 1 1/2 feet. Adjacent to the tank is a buried vault where the influent/effluent piping is located. The tank was constructed where the existing ground slopes, so on one side of the tank the existing ground is level with the base of the tank and on the opposite side the existing ground is above the top of the tank. To provide access to the tank, there is an 8 foot wide access path around the perimeter of the tank. At the time of the inspection I was not able to gain access to the inside of the reservoir, so I was only able to inspect the exterior portion of the tank. The inspection started at the drive way entrance next to the valve vault and what I will refer to as 6 o'clock as looking at the tank from above. The inspection started at the tank access hatch and went counter clockwise around the tank. From the access hatch to the 5 o'clock position, it is apparent that people come up to this location to throw rocks at the tank. In this area there are spray paint markings and multiple small rock pits on the side of the tank. Many of these rock pits have chipped away the tank coating and localized corrosion has stated to occur. Photo 13 shows one of the worse rock pit areas, but many of the smaller pits are in a similar condition. If these are left un-repaired, the corrosion process will continue to erode the steel and eventually cause the tank to leak. It is recommended that these pits be cleaned and recoated on a regular basis. Photo 13 - Devils Thumb - Typical Rock Pits 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 ,,,.vw.mwhglobal.com Eoulder Inspection Docr Page E-14 °i MWH BUILDING A BETTER WORLD The remainder of the tank vertical surface is in relatively good condition with only localized areas of rock pits. The next noticeable area that needs attention is the finished grade around the backside of the tank. At the 2 o'clock point, there was a large low spot with water in the access path. This area does not pose an immediate problem to the foundation, but it is apparent that the area is retaining surface water. This was not the only location where standing water was occurring. From the 1 o'clock position to the 9 o'clock position, water was trapped in the drainage swell. The standing water in the drainage swell was also not posing a problem to the foundation. Photo 14 shows the first area where there is the largest volume of water being retained. It is recommended that the access path surrounding the tank be re-graded to allow proper surface drainage. y j- -i `iyry4r L 7-7 r -y '0 At Photo 14 - Devils Thumb - Standing Water in Access Path Because the surrounding grade on the back side of the tank is as tall as the tank, this allowed me to climb up the hill side and perform a visual inspection of the roof from a distance. The first thing that I noticed is that vandals have thrown small rocks on top of the tank. I was not able see if these rocks were leaving similar rock pits, but It can be assumed that the rocks are damaging the roof coating. Besides the rock pits, it is very evident that there is something structurally wrong with the roof. There are many depressions, low spots, and areas where the steel is dented in. It is also apparent that the roof has deflected to the point of holding water. These problems can be seen in Photo 15. Further investigation is needed to determine the cause of the low spots in the tank, the rocks need to be removed, the damaged roof sections need to be repaired, and the coating system needs to be touched up. If the tank is to be replaced, it might be necessary to replace with a pre-stressed concrete tank, or installing a fence to prevent people from throwing rocks on the tank. 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 ;vww.mwhglobal.com ooulder Inspection Docr Page E-15 Page 15 of 26 MWH BUILDING A BETTER WORLD t` i >j M1J Photo 15 - Devils Thumb - Roof Damage Next I inspected the concrete foundation and the adjacent finished grade. Along the hill side of the tank, there were a couple of areas where the concrete was starting to erode. This can be seen in Photo 16. It is recommended to either protect these areas from further erosion or to repair the area with a topping mortar. Pt 44 ♦ s IV- 7 k yf•~ ii- f I r ~1r, t F f ~r G r ~cj ,vtyr~ kFr-.~ ~ fir, J ~ ~ ` , r Photo 16 - Devils Thumb - Concrete Foundation Erosion 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 .vww.rnwhg1obal.corr Eoulder Iwspectior Docr Page E-16 Page 16 of 26 MWH BUILDING A BETTER WORLD It is also apparent that vegetation is starting to grow adjacent to the concrete footing. To prevent future damage to the concrete, the vegetation and soil should be removed and replaced with a weed barrier and free draining gravel. After the inspection, the City mentioned a couple of other items that need attention. First is the rain guard that in circles the perimeter of the tank. For some reason the rain guard surrounding the tank was installed so that there is a trough around the structure. This holds water when it rains and has the potential to corrode the steel faster. The City mentioned that they thought this was installed upside down and that the water should have been allowed to freely flow off the rain guard. More research would be needed to determine if this should be re-installed in the opposite direction. The second issue is that the internal coating still contains lead. The exterior coating had been previously removed and re-coated with a non-lead based coating system, but the inside has not. This lead based coating should be removed as soon as practical as this presents a potential health hazard if the coating system fails. Summary: It is difficult to rate the whole structure by performing a quick inspection of the reservoir, but there are definitely components of the structure that need attention. The following list describes the known items that need attention and should be maintained on a regular basis. • Rock pits surrounding the tank should be cleaned and re-coated on an annual basis. • Finished Grade around the back side of the tank should be re-graded to allow proper drainage of the site. • Rocks need to be removed from the roof. • Further investigation into why the tank roof is dented and deformed is needed to identify if the possibility of the roof collapsing or failing in the near future exists. • Concrete foundation needs to be protected or repaired. • Vegetation next to the tank needs to be removed. • Rain guard might need to be installed facing the opposite direction, further investigation is needed. • Internal coating needs to be removed and re-coated because it contains lead. References: The following electronic files were provided to MWH by the City and were used as references for the following inspection • 06481_06483x-BV16.pdf 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202,n.v~w.mU~hglobal.com ooulder Inspection Dxx = - Page E-17 - MWH BUILDING A BETTER WORLD Inspection Date: May 4th, 2010 Reservoir: Chautauqua Reservoir The as-builts for Chautauqua Reservoir show that the reservoir plan is in the shape of a trapezoid. The base is approximately 250 feet with a top dimension of approximately 180 feet and edges with a length of approximately 260 feet each. The capacity is listed as 8.0 MG. The reservoir is covered with concrete double tees supported by concrete beams and columns. The double tees are covered with insulation and topped with asphalt and gravel. The perimeter of the reservoir sticks above the finished grade approximately 3 feet and the roof gradually slopes to multiple drains throughout the top deck. Around the tank perimeter there is an access path and the grade is sloping away from the wall. The natural weeds and grasses have grown up to the concrete stem wall, but there were no major problems with the vegetation. There were only a couple of areas where the grasses and weeds were getting tall. Regardless, the area adjacent to the reservoir should be cleared of this vegetation and replaced with weed barrier and free draining rock. The perimeter wall was in good condition. Only at a couple locations were there shrinkage cracks. A typical shrinkage crack can be seen in Photo 17. These cracks are not a serious problem, but should be "V" grooved and sealed to prevent further deterioration. d ' . Photo 17 - Chautauqua - Typical Wall Shrinkage Crack 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 www.mwhglobal.com ooulder Inspection Docr Page E-18 Page 18 of 2b MWH BUILDING A BETTER WORLD The worst exterior problem of the reservoir is the built up roof. It has failed and is past its service life. The asphalt is cracking and the insulation below the asphalt is holding water and is most likely deteriorated. Around the drains, the built up roofing was soft and one can tell that it is retaining water below the asphalt. A typical drain can be seen in Photo 18. It is apparent that the asphalt surface is deteriorated and needs to be replaced. -f~ 115C ' nom! f r ~ n'aT?Ar 4 ,ti r: + a~ t xF r % ~k w .t v}s 6-,1 ;.4 ~`r M1' y J 4 r'~::t (r.• ire ~ v} 1 + ~ ; ar ?',z s t ~ ,,,^yL.~b~ Syr'"~'-. r:+ J J Y ti "E 1 4,k ~ yt~fru 7 .v' ~ r*" S ~ - 'ri ~ ,;{J'st f [ f`'~ r lr~~ f '~~a!'~r }J -1 ifs 1, t.~~ .i Photo 18 - Chautauqua - Typical Drain Condition Other appurtenances that were looked at were the vent piping and the access hatches. Both were in working condition, but the coating on the vent piping has failed. Photo 19 shows a typical vent pipe with the condition of the coating. The existing coating should be removed and re-coated to prevent further erosion of the steel pipe. .a S Photo 19 - Chautauqua - Typical Roof Vent 1801 California St. TEL +1303 291 2222 Suite 2900 rax +1303 291 2221 Denver. Colorado 80202 vww.rnwhg1obaI.com Eoulder Inspection Docr Page E-19 Page 19 or` 26 MWH BUILDING A BETTER WORLD Halfway through the inspection, I did get an opportunity to go into the main access hatch. The access is where the metal stair goes to the bottom of the reservoir. At the time of the inspection the water level was low and this gave me the opportunity to get a look at some of the concrete liner and the underside of the concrete double tees. It was apparent that the concrete liner was corroding and that the reservoir was leaking at the concrete liner joints. In some areas it looked as if in previous repairs, they tried to prevent the liner from moving by attaching metal plates across the joints. The plates that were visible looked in good condition, but it was apparent that the joints were leaking. Photo 20 shows the deteriorating concrete liner, areas where the joints are leaking, and how the concrete double tees sit on the exterior wall in this location. F ` i Photo 20 - Chautauqua - Concrete Liner at Access Hatch One item of major concern is the condition of the shear tabs of the double tees. I happened to look up at the joints of the double tees and noticed the shear tab that holds the double tees together was corroded and non functioning. This is one tab out of many, but it can be concluded that more tabs are in a similar condition. If this is the case, the roof diaphragm no longer functions in the manor it was designed. Any lateral loads will not be carried properly by the double tees to the shear walls and the external stability of the reservoir can be in jeopardy. Photo 21 shows the corroded concrete double tee shear tab that was in the reservoir access area. Further investigation into the condition of the roof shear tabs is necessary to determine the adequacy of the roof system. 1801 California St. TEL +1303 291 2222 Suite 2900 -AX +1303 291 2221 Denver. Colorado 80202 ,P.vw.mwhglobal.com EE )Lilder IlSi;eG'!Ufl.Dxx Fare 2i 26 Page E-20 MWH BUILDING A BETTER WORLD Photo 21 - Chautauqua - Typical Roof Shear Tab After the inspection of the reservoir, I briefly inspected the PRV. The PRV is located adjacent to the Reservoir and is mainly a cast-in-place concrete building. The concrete that was visible was in good condition and I saw no major problems with the structure. Summary: It is difficult to rate the whole structure by performing such a quick inspection of the reservoir, but there are definitely components of the structure that need attention. The following list describes the items that need attention and should be maintained on a regular basis. • Perimeter wall shrinkage cracks should be "V" grooved and sealed to prevent future erosion. • Built up roof system has failed and needs replacing. Suggest considering a separate roof system that isolates the roof from the concrete double tees. • Roof vents need to be re-coated • Further investigation of the internal concrete lining should be conducted to determine the condition and remaining service life. The leaking joints can lead to problems along the perimeter of the structure including settlement issues and possible contamination of the reservoir. • Further investigation of the double tee shear tabs is needed to determine if the roof can perform as originally designed. New tabs might be needed, or the entire roof might need to be replaced. 1801 California St. TEL +1303 291 2222 Suite 2900 -Ax +1303 291 2221 Denver. Colorado 80202 v, .vmmwhglobal.com Eoulder Inspection Dxr = Page E-21 - - MWH BUILDING A BETTER WORLD References: The following electronic files were provided to MWH by the City and were used as references for the following inspection 00131.pdf • 00132.pdf • 00135.pdf 03042.pdf • 22213_22219-Chautauqua Res Improv.pdf Inspection Date: May 4th, 2010 Reservoir: Booton Reservoir The as-builts for Booton Reservoir show that the reservoir is actually a tank within a tank. The external tank is 173 foot in diameter and the internal tank is 68 feet in diameter with a capacity of 0.6 MG. Both tanks are pre-stressed concrete tanks that are completely below grade. At the time of the inspection, access into the above grade hatch was not possible so the only aspect of the reservoir that was inspected was the PRV vault. The PRV vault is located down the hillside from the reservoir and is cast-in- place concrete. The condition of the PRV was in good shape and no further comments are necessary. Summary: • The reservoir was not accessible for inspections therefore the condition of the buried tanks are unknown. These tanks were constructed within the last 20 years and the City staff has indicated that they have had no problems, so it is assumed that the tanks are in good condition. Regular inspections should be performed to verify the tanks are performing as designed. References: The following electronic files were provided to MWH by the City and were used as references for the following inspection • 28200_28214-NoTerminalWaterTank.pdf 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 :vww.mwhglobal.com ooulder Inspection Docr Page E-22 Page 22 of 26 MWH BUILDING A BETTER WORLD Inspection Date: May 4th, 2010 Reservoir: Gunbarrel Reservoir The as-builts for Gunbarrel Reservoir show that the reservoir is an above ground steel tank with a plan diameter of 130 feet and a capacity of 2 MG. The tank is approximately 20 feet tall with a roof that overhangs the side walls by 4 feet. Below the overhang is a partial soffit that goes from the tank wall to the midpoint of the overhang. Surrounding the tank and the adjacent land is a security fence. This fence and regular maintenance seems to have kept the tank in great condition. For being built in the 70's, the tank visually looks in good condition. The inspection started at the access ladder and went counter clockwise around the tank. The exterior surface of the tank was in good condition with only a few minor surface problems. As I walked around the tank, it was apparent that there was a little more damage on the West side of the tank. Considering it was really windy at the time of the Inspection, it can be concluded that the wind might have a tendency to blow rocks against the tank. All rock pits were relatively small with only small amounts of corrosion starting to occur. A typical rock pit can be seen in Photo 22. It is recommended to clean these pits and re-coat on an annual basis. Photo 22 - Gunbarrel - Typical Rock Pit As I was inspecting the exterior surface, I was also inspecting the concrete slab-on- grade with thickened edge. The foundation slab looked in good condition and there were only a few locations where the vegetation was growing over the slab and next to 1801 California St. TEL +1303 291 2222 Suite 2900 -AX +1303 291 2221 Denver. Colorado 80202 :vwmrnwhglobal.corn Eoulder Inspection Docr Page E-23 Page 2 3 cf 2u MWH BUILDING A BETTER WORLD the tank wall. This vegetation should be cut back on a regular basis. I would ultimately recommend removing the soil and vegetation next to the slab and replacing with weed barrier and free draining rock. There was no evidence of the finished grade being too high or low and it appeared that the surface water was draining away from the tank. An example of where the vegetation was growing over the slab can be seen in Photo 23. o= r,rv a~tP" a a A`~i31,.2y..;ic i c. $a I s !per ~ w S w~ all. TP, -e•:. .s "~'f[a ,714. 22 w, s A-k Photo 23 - Gunbarrel - Example of Vegetation Overgrowth Another area of concern is at the soffit. It is apparent that birds are nesting in between the soffit and the roof overhang. Photo 24 illustrates a typical area of the soffit where there are bird nests and bird excrement down the exterior surface. This is not an ideal 1801 California St. TEL +1303 291 2222 Suite 2900 FAx +1303 291 2221 Denver. Colorado 80202 ,,,.vw.mwhglobal.com ooulder Inspection Dxx Page E-24 - °i MWH BUILDING A BETTER WORLD condition for the coating system and can overtime break down the coating. It is recommended to remove the nests in the fall, clean the surface, recoat where necessary, and then install wire mess between the soffit and roof overhang. a1 1, t Photo 24 - Gunbarrel - Typical Soffit Condition Other than those items listed, the tank exterior was in good condition. Due to the short inspection timeframe, I did not get an opportunity to inspect the roof or the inside of the tank. After inspecting the tank, the City did mention that the inside of the tank needed to be re-coated. This should be put on a long term maintenance schedule. One oddity of the reservoir is that there is an external box with what looks like a corrosion protection system. The City did not know what it was and if it was working. More research should be conducted to fully understand the function of the box and if it is working. If this is integral to the protection of the tank, it would be good to know how it works and if it's working. This might need to be replaced and maintained on a regular basis. 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 ;vww.mwhglobal.com Eoulder Iwpection Dxr Page E-25 Page 25 of 26 MWH BUILDING A BETTER WORLD Summary: It is difficult to rate the whole structure by performing such a quick inspection of the reservoir, but there are definitely components of the structure that need attention. The following list describes the items that need attention and should be maintained on a regular basis. • Rock pits should be cleaned and re-coated on an annual basis • Vegetation should be kept from growing over the slab-on-grade and ultimately the adjacent soil should be removed and replaced with weed barrier and free draining rock • The bird nests and excrement should be removed from behind the soffit and along the tank. After cleaning the area, bird screens or wire mesh should be installed between the soffit and the roof overhang to keep birds from nesting behind the soffit. • Investigate the purpose of the external box that might contain a corrosion protection device. References: The following electronic files were provided to MWH by the City and were used as references for the following inspection • 4457-4469 Gunbarrel Tank- General layout & details pdf • 06470_06472_B&V Docs_Gunbarrel_Tank.pdf This concludes the partial inspection of the City of Boulder's Finished Water Reservoirs. Additional information can be obtained from MWH by request. 1801 California St. TEL +1303 291 2222 Suite 2900 FAX +1303 291 2221 Denver. Colorado 80202 .vww.rnwhg1obal.corr Eoulder Iwspection Docr Page E-26 Page 26 of 26 momomm Page (February2411) F"1 Utility of Boulder Final Draft Water Master plan City F~ . Apper►d~x MWH MEMORANDUM 8MVIJNG A BETTER WOULD TO: Memo to File DATE: January 30, 2011 FROM: MWH Business Solutions Group REFERENCE: 1008566 - WUMP SUBJECT: Asset Management Update for BRWTF and Stranded Facilities 1.0 Introduction As part of the City of Boulder's 2010 Water Utility Master Plan, MWH performed an asset management update for the City. The objective of this task was to help the City better estimate the overall renewal and replacement Capital Improvement Program (CIP) and maintenance budgets. In this effort, MWH worked with the City via workshops, desktop analysis, and field observations to evaluate, refine, and update the condition scores and replacement cost estimates of facility assets at the Boulder Reservoir (63rd St.) Water Treatment Facility (BRWTF) and stranded facilities. The stranded facilities considered in this analysis included: • 101 Pearl and Sunshine PRV facilities • Sunshine, Orodell, Maxwell and Kohler hydroelectric facilities • Gunbarrel, Maxwell, Booton, Devils Thumb, Kohler, and Chautauqua reservoirs Primary activities included: • Asset Data Review and Gap Filling: The City's asset data for the facilities mentioned above were reviewed and analyzed for completeness for condition-based planning purposes. Analyses of the asset base included completeness and distributions of key parameters such as asset use, size, material, age, and condition. Data gaps were addressed using City and MWH staff knowledge, as well as professional judgment. • Asset Condition Scoring: Condition scores were developed with City staff for each asset through workshops, desktop analysis, and field observation using industry best practices. • Renewal Cost Forecasting and Budget Scenario Analysis: Long term (50-year) cost forecasts were developed for the City's facility assets. The results of these long-term forecasts enable the City to determine budget levels needed for the long-term renewal and replacement of its assets. F-1 Key potential benefits to the City from this effort include the following: • Having a consistent, high level estimate of the current condition and potential long- term reinvestment needs associated with its BRWTF and stranded facilities. • A documented outline of a clear, defensible, and repeatable methodology for assessing asset condition, and enabling condition-based prioritization and financial forecasting across the City's infrastructure asset base. • The initial condition scores, unit costs, and forecasts developed as part of this effort provide the foundation for future analyses and ongoing refinements of the City's financial needs as additional information is collected, and/or as management priorities change over time. • Early awareness of potential gaps between current asset renewal budgets and expected long-term financial needs to adequately manage the condition and probable failure of assets will enable the City to develop sound long-term financial strategies to address potential budget shortfalls. This proactive and comprehensive understanding of the City's condition profile will allow the City to address its current and expected future asset needs through careful planning and management of its inspection, maintenance, and asset repair and replacement activities. Finding highlights from this analysis include: • Data for the BRWTF were more complete than for the stranded assets. However, further review of project and facility documents helped to fill gaps. In a few instances, some gaps in original cost and installation date remain; however, the renewal forecast workbooks have been structured to allow this information to be provided by the City at a later date and most related updates to occur automatically. • The condition scores for BRWTF assets were generally good. However, the condition of some dams and treated water reservoir tank roofs, piping, and valve vaults was generally worse. • The City may want to start planning how to address the significant cost of renewal to the BRWTF ($128M) that will be required in the 2045-2055 period, hydroelectric facilities ($10M) that occurs over 2024-2049, and reservoirs ($118M) during the mid-2050's. As part of the scope of this effort to be consistent with the Pilot, this asset management effort is built off of the output format, condition fractions, and cost factors developed during the Pilot. It took an additional step to develop a more robust analysis tool for the City utilize for consequence-based asset analysis for capital improvements planning into the future, which will serve as an important foundation for a more strategic risk based analysis down the road. Conclusions and Recommendations are included at the end of this memorandum in Section 5.0. 2.0 Methodology The condition scoring and renewal forecasting for the BRWTF and stranded assets are outlined below. They are critical elements of effective asset maintenance and renewal planning. This project did not aim to explore the important risk (including consequence of failure) elements of each asset, although this is recommended in the near future. However, condition scores were created and updated for these assets. It will be important for the City to evolve to a risk based approach to best enhance their asset management to build justification of asset renewal priorities and related decisions and strategies. F-2 The overall approach for developing condition scores and renewal forecasts is illustrated in Figure 1 below: Figure 1. Overall Approach to Condition Scoring and Subsequent Renewal Forecasting These steps involve the following: • Compile & Analyze Existing Asset Data: Available asset data were compiled from the City's existing databases. Where necessary, data gaps were filled with estimated values based on discussions with City staff and analysis of related readily available information. Spreadsheets capturing this information were updated and enhanced for condition scoring and renewal forecasting purposes. • Develop Asset Condition (Probability of Failure) Scores: Asset condition or probability of failure (POF) scores, based on available information and workforce knowledge, were assigned to each individual asset. An industry standard scale of 1 through 5 was used, with "1" representing very good condition, and "5" representing very poor condition (See Table 1 below). • Capital Improvements Calculations & Analysis: The asset data were utilized to generate the asset renewal forecasts and create a foundation for the analysis of capital improvement needs. • Develop Inspection and Renewal Forecasts: Useful lives were carried forward based on the probability of failure and are used to forecast the annual cost of renewal of assets. Probability of failure scores for the City's assets at these facilities were estimated in accordance with industry best practices outlined in the International Infrastructure Management Manual (IIMM). Information related to asset condition, including use, age, material, existing F-3 condition scoring information, and existing City staff knowledge was utilized in making this condition assessment. The data gathering and analysis was performed offsite, as well as in interactive workshops with City staff. Figure 2 shows the probability of failure scoring process applied in this project. Information was sought, provided, captured, and evaluated from staff knowledge, available data and records, and asset attributes to develop the initial probability of failure score for the City's linear assets. Operations Staff Available Knowledge Condition Data Asset Age Asset Attributes Initial Probability of Failure Score Figure 2. Summary I>f ,:ilure Scaring Process Table 1 presents the condition scoring system used in the condition analysis of assets to aid in the development of the probability of failure score. This rating system is an industry standard for asset management and comes from the International Infrastructure Management Manual. TaNa 1: Asset Condition/Probability of Failure Scoring Descriptions Condition Renewal Score Scoring Definition Required Very Good. Sound physical condition. Asset likely to perform adequately without major work 0% for 25 years or more for structures and for 10 years or more for mechanical and electrical assets. Good. Acceptable physical condition. Minimal short-term failure risk, but potential for deterioration in medium- to long-term (10 years plus for structures and 5 to 10 years for 10% mechanical and electrical assets). Only minor work required, if any. Fair. Significant deterioration evident for structures and deterioration beginning to be reflected in performance and higher attendance for maintenance for mechanical and electrical assets. Failure unlikely within next 2 years, but further deterioration likely and major replacement likely within 10 20% years for structures and within 5 years for mechanical and electrical assets. Minor components or isolated sections of the asset need replacement or repair now, but asset still functions safely at adequate level of service. Work required, but asset is still serviceable. Poor. Failure likely in short-term. Likely need to replace most, or all, or asset within 2 years. No immediate risk to health or safety, but work required within 2 years to ensure asset remains safe. 40% Substantial work required in short-term, asset barely serviceable. Very Poor. Failed or near failure. Immediate need to replace most, or all, of asset. Component effective life exceeded and excessive maintenance costs incurred. A high risk of breakdown with serious impact on performance. Health and safety hazards exist which present a possible risk to 90% public safety, or asset cannot be serviced/operated without risk to personnel. Major work or replacement required urgently. Source: Adapted from the International Infrastructure Management Manual, Version 3.0, 2006 F-4 Beyond a condition analysis of assets to determine their probability of failure, risk scoring is an important next step of enhancing asset management at the City. Risk-based planning determines budgets needs based on current versus planned target risk levels for the asset base. Priorities for investment renewals are based on risk levels, and success can be measured by the risks managed or reduced at the end of the year. Risk-based planning drives the strategy implemented for each asset. In light of limited resources, a more proactive strategy (e.g., condition assessment, predictive maintenance, or routine maintenance) could be implemented for higher risk assets, while a "run to failure" strategy may be most appropriate for lower risk assets. This strategy allows for staff and financial resources to be directed most cost- effectively. As can be seen from Figure 3, the probability of failure scoring of assets is an important component of the risk score. Additionally, the consequence of failure is the second component to develop risk scores. Consequence was not analyzed as part of this project, but it is important for the City to consider performing such an analysis to strive for an enhanced asset renewal forecast that is risk-based to attain the benefits of having risk perspectives described above. By combining the product of these two components, a risk score can be generated for the City's assets. HIGH _:7C-'_-D~MCu] ~~';~=AML Strategy: Strategy: Probability Reactive Mix of react ve and of Asset Strategies proactive strategies - Fai[um (operate to failure) dependent on owner (1 to 5) preference and site specific issues Strategy: Proactive condition andlor performance LOW monitoring RISK ZONE Low LOW Consequence of Asset Failure HIGH (II to 3) Figure 3: Risk-Based Strategies for Various Asset Risk Levels When analyzing the assets for consequence of failure, the general approach starts with a screening for the economic impacts of an asset failure (looking at repair cost factors based on size, depth, and traffic issues) to arrive at an initial consequence of failure score (on a scale of 1 to 3) at the systems level. Scores for the City's assets are assigned to develop a relative ranking based on the economic, social, and/or environmental (triple bottom line) impacts. It is noteworthy that City staff may want to revisit the condition/probability of failure scores developed during this project on a regular basis, particularly for special facilities and key customers which are likely to change over time. This will help the City keep its Renewal Forecast updated and as accurate as possible for the condition basis. F-5 As part of the condition scoring process, City and MWH staff performed field investigations to develop or confirm some of the workshop- and desktop-based condition analyses. MWH used structural and hydroelectrical discipline engineers to perform these field inspections for the hydroelectric facilities and the storage reservoirs. Also as part of these inspections, engineering information provided by the City was reviewed and a brief summary of findings and condition were noted. The approach to these field observations are further detailed in Section 5.2 of this Master Plan document. 3.0 Data Analysis Facility asset data was collected and analyzed for the BRWTF and the stranded facilities. This section provides an overview of these efforts. 3.1 Source Collection Existing spreadsheets (e.g., Microsoft Excel workbooks) containing asset data for the BRWTF and stranded facilities were examined for completeness and relevancy. These initial files included: • "BRWTP - 2008.xls" • "Hydroelectric Facilities - 2008.xls" • "Treated Water Storage Tanks - 2008_Data updated 2010.x1s" Data gaps were filled from facility document references, City staff and MWH knowledge, and field observation. General examples of documents consulted include: • Facility reports • Facility drawings • Facility data spreadsheets and updates A few specific examples include: • "BRWTP_Rec_dwgs.pdf' • "Water Storage Tanks_Hydro_PRV_Stations_2010R01.xls" • "1985-1995-Orodell Hydro As-Built Drawings.pdf' • "Hydro Facility Information.pdf" • "Storage Tank Capacity Graphs.xls" • "Kohler Roof Inspection Report 2007.pdf' Key data of each type of facility (BRWTF, Hydroelectric, and Treated Water Reservoir Storage Tanks) were summarized on an output tab in each asset management workbook in a format based on the City's existing and preferred asset management format of the Betasso Water Treatment Facility (BWTF) asset management pilot project. 3.2 Asset Management Workbook Preparation Initial facility data spreadsheets to be used in the asset management probability of failure and renewal forecasting analyses were provided to MWH by the City to examine and identify pertinent gap filling needs after consulting existing facility documentation. Several updated versions were provided by the City to roll-into these spreadsheets and the analysis. When MWH reviewed and analyzed these spreadsheets, the following observations were made: • Data gaps existed, and MWH worked with City staff as necessary to fill them. F-6 • Some manual breakouts of data and other manipulation were needed to tailor the functionality of the workbooks to the application of probability of failure and renewal forecasting analyses. • BRWTF data was more complete and updated than the stranded facilities. The stranded facilities required significant gap filling. • Significant overlap of line items in the hydroelectric workbook existed; line item assets needed to be distinguished from other 1319XX Improvements" projects to make sure they were broken out from the improvement line items to eliminate overlap in probability of failure scoring and renewal forecasting analysis. This was done by eliminating improvement line items from the analysis. • Condition scores of the stranded facilities developed during workshop analyses with City staff were verified during field observations with engineers of specialized disciplines. 3.3 Asset Management Workbook Organization and Functionality Facility data workbooks of the BRWTF and stranded facility assets have been adapted into new spreadsheet files for the purposes of probability of failure scoring and renewal forecasting. The names of these workbooks are: • BRTWF = "BRWTF_AM_2010_v1-24-3.xlsx" • Hydroelectric facilities = (`Hydro&PRV_AM_2010_v1-24.xlsx" • Treated Water Reservoir Tanks= "WaterStorage_AM_2010_v1-24.xlsx" All three workbooks function in a similar manner. Screenshots of each workbook are included below: rln A - a . _I_ ir 11 11rr_ a @ Formulae Data Rw¢w Ycrv acobat iW _ rt Y 3 I.- I'- Po9c LYo ?rial - m - A a ° = as I+~^ raP rea „eneral - NOrRIEII Bad " fJ - cagy - ] F, .rJ Palle tl t 11 '~T = - .f.r]tL-enter- - . m o wrJ', Ona ere at Good Neural _ tr',stil Delete F„ '16 aG JFu nd mn ci - _ - F-aft, -a57aolt. - - ~`-c'- Fllx-<xkd- SecurM1y war g utoma.ir cpaaxe of IinY.. Fa. Le.n tlis:el.o F rz.. z C14 f e t L [ - _ n I 1 rc _ 5l Il u - 0 DRAFT DOCUMENT C d' P etions I n.r mo e r comae: © M W H IF- 8 + 1C a City of Bou der e E.Sm.3.a....~.e ."ll T a1 I, .1 TOral F_sti ei Prnienr CCOZrs 131r. I@L. 2d%i BRWTP .C o~a nal R urea zelo zmo zol6 zoro - -al ✓FoU'~. ~m,.t Ieual ume,n u z e use a Leoar am r.: 1 y a atn ¢ at4e F.,: r aerrn~~ 1 ~uo. IP:r>Irr, b ,ISr eu a. - mllxa m . n 3 a0 ra r (..IOE yrJ. 10 2 A R 50 I e aPL 6 11 .1 Tdr5 -11 F< JFr..ltl. Fb, Rv Yf-.~rcJF x pt 11 n 1, M "1 1 1- 1 1; 1h 1, -'I ( Z_.]_ C P 19 1 210 38~S6J01 ! 3g _ I 8990Y5 F 1155454 y 14551 11 1 8 rwod V 22 2 K b 411 2(511W PI ILL4 b 389A3i'. b 1028959 3 IRE:. f390arI s - - - V 201 72 1. a'. 47. i'Ll 'C A 1 91 Ii 5 b ]58 I 1_ EPEi_~4_ - 2f 1 -9] 1] 50 20SO~ILS -F__ y_9?6J i _2.50E61F 2]$OE6 F IyR_- 201 A(S P.. `m 4r3 11 1 -1 lake V:uln 25 1 9] 4 50 20501 I LS o.'n le: i 54,910 11 1:53A'' 3 b59 0 Fac Re.cedl - r Raaay f t rN.otle !i < rl Figure 4a. Screenshot of BRWTF Asset Management Workib,- F-7 :~J Home Insist OsSe U'.. F-I,, Datz Revixw View avobat F} - I'T X vuc = _ aad z A-lum - d' 411e1 ID A e - _ _.?,-I : ep tat „m.i41 Normal Copy ~ ,Fill - ~nx s r u :8 '~na eood rn ral Inoert De etx F mx a .a~ ,f Fermat aalnler _ Fo rrol a e„eu. - ~Cxil- a _eerl- D c15 f= _ _ J 7 L- DRAFT DOCUMENT C. diito l FFactlnn „tT., r, Ir,r.real La © Mw" n s' ~ z o1 _ ~ r „nF I ~ nn t . BUSIf~ n j/ I Oi _ 1, 55 1. 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Screenshot of Hydroelectric Facilities Asset Management Workbook J Home Inszrt Sx -4yovt Fom Ulas Datz Revizw Uew Scobat _ _ !t X ~lolur[' Sh', ton nr cl nzs Hiad 105 E U QQ Fenrt- „J r..D~r artom + vx1Y r 4x I J 4 J Drn, Dr F az - lar9 n=Oneniat on S-e : Hxcl fazl:6 d -le - oSe zl0 4'9n i0 R^ta:. E; Tit'.e ASh - Griot Drinl ...1 Pene n r, J Rx9+y~p ,.al_r, Fir Srez -.n. Hoge yy SecmllY WarninY zr amo.i p to of linl.: na: tern diarelcd F r:., X =13 1G P C C F F H I I K I- I:I ICI n F - 1 DRAFT DOCUMENT 2 Pzojw4 LRZt FaUws IMnrel EYwrel 4 [orwlnonFracmns«mali:oe, c. I°rr.. © MWH _ri z °o. coASasoronae c mi mz 15x wb. BUSINESS SOLU'i I( B 1 0~ G dit W.IIBi t5': fl ~ III _ a ee IL 1N 1 ` 12 s • A < 3 jp e ° City of Boi der C.- city Water storage Tanks (Reservoirs) Qr . rn ~,e., r..rtr 9a..o R>nL.e, {.a .a,o . rr.,r r R Lo .,<e A 2 6~ 2 65 2~ , nD r d ,tl>~I 1 -,1, r - ~A,GreGr _ _ ,.Y dF Breda - ~ 5n5 2t3~ 1 r<5 a a,x=o s In➢u v.m radKDa t v:..,~r. a 6. t e :u bs x nand C-V 22 ~o -IL 201° 0 0 CI.Si 4 5~'03J $ 5].983 F rle R.cords 1814 UI actor: cs fmcrearoerae'waUa be D[ndtoa c0 u =L tone R!sev>r M'melaaears Elmt oal=I 21 2 .0 10 a38 2010 0 0:-I i 11104 S 85639 6 845889 F Ily R.0olds 19]4 nb tneC<tFaecnro.........m Fia.. - I G~nb.rrelRxsxrvoir Loatino;lnelioi 25 23 36 2W5 0 m I=x i 09.61] S ',38.266 £ 3.8.:65 F cards 1999 ProivtiiKTl GUn>ave r:atrr 6foi=o. iar.: F' L TaH. 15 n x . - [2 rdr 268 201A . 9 89120 E ass £t4 d 9)3811 F - 1.6. CCE:k:eselr P 1 r• . r r - - - ~ r-F'O~ltLa..• s[prM1--R OuWul Vierv ;'"Watnitma¢0.ertewalfmttrfll F SOrr GraVh fadi 11 r =i. reated Water Reser\;,: agr Tanks gement Workbook F-8 A general overview of the description and instructions for the sheets in these workbooks is provided in Table 2. Table 2: Description of Tabs Contained in the Asset Management Workbooks Tab: Tab Description/instruction: Reference Info--> Cover sheet for tabs containing reference information. Revisions Lo Documents the revisions of the workbook. Key to indicate what highlights and other markups Legend indicate. Information regarding condition assessment and asset Assess Info valuation. Client Data Data set provided b the City. Manipulated data set for examination during Condition CondAssesmnt Workshop Data Scoring Workshop June 17, 2010 Data Entry--> Cover sheet for tabs containing data entry cells. Current data set for asset management purposes. Serves as the reference tab for data in other tabs. Data should only be revised in this tab, and the revised version of the workbook saved as a new version. Make sure that numeric values are recognized as such by ensuring that the cell type is "General" or "Number" via Data Ent Tab the HomelNumber menu in Excel. Data Output--> Cover sheet for tabs containing output of the analysis. Data output view designed to match that of the pilot project. Suggest interface for review and examination of Output View data b the City. BRWTF Renewal Forecast Data used in preparing the renewal forecast for the site. 50-year renewal forecast for capital improvements for 50 r Graph the site. For treatment plants, an annual breakdown of costs by Discipline Graph discipline Civil, Mechanical, Electrical). Facility Graph A breakdown of costs b facility for the asset set. All three workbooks contain an "Output View" tab that is the preferred view of the City of the asset data and similar to the BWTF pilot project. A screenshot of this tab is shown in Figure 4 for the facilities considered in this project and in Figure 5 for the BWTF. F-9 .ti . • . 1n e,.. - r~~ e.e .ooa ,...,e J.a. M'~ x.«.... Ql tf~ "r..,. . , 9 _ r ~ S Jia J.. , _ ti J 9..~ .r.n. . ''-~fok!~fd ~.a,R. r... .ef• N ~ -f ' vre r.vxr. [mdhbn F..vbw vow za s'< rs. ! w stTS,~. t.11 13SY 11A 10 T, Wti wy.. ..may... % a, w - ..+hs: - r9 4 } 1fr f ~ f FY•c rx. N'. ,q0 Srw-... wM1n u• _ _W 3 c+.b K. L° iYf S1 rr..+, ---tb,: F f ••1 f Ju.•y f .X !u c+.a va. Ate ,ON 13 rr ma 4wc OEL f r~ vY of i W -r.•nsw. 0- f 'A f e A r1P.t4 muK.ar ,pO p'f.+ne+=,.u.t .w v~.5 wv++:ir h : .f.Irf 1 1 : Pet R xvK..p Yb n•+cSVfWrsv ne "ar: 10 R0,4RI 9.MFR iW tlwFFH-1,OMf./.n. l.a~r1 45 • ! R,1 R, a .w.. we,..1 6+ 13 u J4+ h M11 1 1 _ _ IfR R1 n.1ia ld Rrw•. m,r.+! !R +.•m;'•,u M 5 W'!v': A :x9 f Cf 1 R `A 1P➢0 i1 u 52 rrc~.Ywn 01 510 SA .r f Ibi!-k.•O Y.P'CO.m vrs.V b1N ~ 4~i7 lY~• Figure 5. The Output View of the Asset Management Workbooks of This Project Emulates the View From the BWTF Asset Management Pilot Project Seen Here Detail regarding the "Output View" tab is included in Table 3. Note that nearly all columns in the Output View tab pull automatically from other tabs within the same workbook. The purpose of this is to maintain the consistency, completeness, manipulative flexibility, and versioning of the data. Except for the project cost factors at the top of the "Output View" tab, data should only be modified on the "Data Entry" tab. Table 3: General Descriptiansilnstructions of the Columns in the Output Vie-w Tab for the Asset Management Workbooks Column on the Output View Tab: Column Descri tionlinstruction: Facility Facility name of the asset group. Automatically references the data tab, so only modify this on the data tab, not the Output View tab. Item Concise description of the asset. Automatically references the data tab, so only modify this on the data tab, not the Output View tab- Original Sort Order Top-to-bottom organization of the data. Utilize this to restore order of the data after sorting. Automatically references the data tab, so only modify this on the data tab, not the Output View tab_ Condition Ranking Probability of Failure ranking for the asset. Automatically references the data tab, so only modify this on the data tab, not the Output View tab. Original Useful Life (OUL) Typical useful life of the asset beginning at its installation. Automatically references the data tab, so only modify this on the data tab, not the Output View tab. F-10 Remaining Useful Life (RUL) OUL minus the difference of the present year and the Year of Installation. Evaluated Remaining Useful Life (EvRUL) RUL adjusted for condition via a condition factor. Year Due Expected year of end of life (expiration) of the asset. Based on the RUL. Quantity (Qty) Quantity number (based on units) of the asset in use at the facility. Automatically references the data tab, so only modify this on the data tab, not the Output View tab. Unit Unit of the quantity of the asset. Automatically references the data tab, so only modify this on the data tab, not the Output View tab. Internal, External, Simple, or Complex Expresses whether the replacement of the asset can typically be performed by City staff ("Internal"), or whether an external contractor or vendor ("External") is required to do the work. A "Simple" designation is used to classify replacement work of minor cost; an asset is labeled as "Complex" if the replacement work is expected to be more complicated and thus more costly. 2010 Direct Cost Asset replacement cost excluding Project Cost Factors. Automatically references the data tab, so only modify this on the data tab, not the Output View tab. 2010 Total Project Cost Asset replacement cost including Project Cost Factors. 2010 Total Replacement Value Asset replacement cost including Project Cost Factors, adjusted for concrete structural assets to better reflect actual costs. 2010 Cost Basis Asset cost reference. Year Installed Date asset was installed and began operation. Basis for RUL calculations. Comments Remarks pertinent to asset management regarding the asset. Several assumptions exist for the probability of failure scoring and renewal forecasting analyses. These include: • Assets considered in these analyses include those with any of the following characteristics: o One year or greater expected useful life o Greater than $5000 expected replacement value o Are key to safety o Need significant routine inspection or maintenance o Are key to regulatory monitoring • BRWTF was the only facility for which analysis was performed at the discipline level (e.g., Civil, Mechanical, Electrical), at the City's direction. This level of analysis is not as relevant for the stranded facilities at this time because of their simpler composition. • Facility data and information, including costs, provided by the City is assumed to be correct and up-to-date. F-11 • Simple and Complex costs are calculated using the existing 2008 cost factor basis. • The 2010 Condition Rating takes the place of the 2008 Condition Rating. • Stranded facilities and their assets were scored as a two, unless knowledge or observation justified a different score. • The methodology and appearance of the renewal forecast data was to be as similar as possible, excluding improvements viewed as necessary or preferred by the City, to the BWTF asset management pilot project workbook ("Betasso WTP - 2009 12-8- 09.xls") and report ("Betasso_WTP_AM_Pilot_Summary_Draft_Aug09.pdf"). • Probable costs were based on AACE International (Association for the Advancement of Cost Engineering) guidelines for a Class 4 estimate. 4.0 Results 50-year repair and renewal forecasts were prepared for the BRWTF, hydroelectric and PRV facilities, and treated water reservoirs. The results of these forecasts are presented below. 4.1 BRWTF Repair and renewal costs were estimated using the methodology described in Section 2. Figures 6 through 8 present the results, reflecting a forecasted 50-year investment need of $190M, or $3.8M annually, as shown in Figure 6. BRWTF 50-Year Renewal Forecast MWH BUSINESS SOLLMONS City of Bou,der 580,000.D00 S70 000.000 $bU,UUU.000 $ SI1,000JK0 540.000.000 SAD,0UIUKK1 520,000.000 % Average: $S.Wperyear S 10 000.000 n a o n n n n n n n n o o n n : n ci n n n n n n n ri ci n n c r. n n n n n n n n n ri si n n n n n n r', n N N N N N N +J N N N N N N N 1 N N +I fl N N N N N N N N N N N N +1 N N N f-I l +I N N +9 PI N fJ N +I N N N +1 Figure G: 5RV,/TF 50-Year Renewal Forecast As can be seen from the Civil, Mechanical, Electrical breakdown of the forecast in Figure 7, costs in some years are projected to exceed the annual average. These are analyzed below: F-12 2027-2030: Approximately $24M in mechanical needs are expected in these years. This is largely due to equipment reaching its expected useful life in areas such as the DAF building, Filter Building/High Service Pump Station, Raw Water Pump Station, Administrative/Chemical Building, and miscellaneous mechanical needs across the site. 2037: Instrumentation and control renewal at the Filter Building/High Service Pump Station, general power electrical assets across the campus, and the 30' magnetic flow meter are the main contributors to this $5.8M need. 2039-2040: $10.5M is needed among these two years as the PLC-4B and instrumentation and control in the DAF Building reaches the end of their lifespan, and the High Service Pump Station in the basement of the Filter Building and the filter surface water washers in the Filter building expire. 2042: In the Administrative/Chemical Building, miscellaneous electrical assets will reach the end of their useful life, as well as the motor control center in the Filter Building/High Service Pump Station, to be the largest portions of the $5.6 investment needs for 2042. 2046: Nearly $27M of miscellaneous electrical infrastructure is expected to reach the end of its useful life across the treatment plant at Administration Building, Filter Building, Raw Water Pump Station, and throughout the campus grounds. 2047: This year, a half million dollar transformer comes due along with the high service pumps at the Filter Building at a price of $43M. 2050: Most of this cost is due to the 48" raw water line at the BRWTF expiring at a cost of $8M. 2051: Much of the civil infrastructure is expected to reach its useful life and require repair or replacement at most of the buildings on the site and across the site grounds. Additionally, the pipes onsite reach the end of their useful lives. The combination of these infrastructure components reaching their useful lives results in a price tag of $75M. 2055: The 42" raw water DIP extension, carbonic acid feed system, the 30" wastewater line at the filter building, and a variety of piping across the campus are set to expire at a cost of about $9M. F-13 BRWTFRenewal Forecast By Discipline QMWHv uTL'ys 570009 nqQ S 5. 3,000 000 ;3n,nMl,nnU s deamal ■ Mixhanical ■rrvl 5311.[I[N1.000 SEOAK) OQU $mom o0o Figure 7: BRWTF Renewal Forecast By Discipline In Figure 8, big ticket items for the General Site Work category across the BRWTF campus that will require renewal for the next 50 years include significant portions of its mechanical, electrical, and civil components. In the Filter Building, most of the $57M includes replacement and renewal of the majority of its components as they become due. The amounts hovering around $25M each for the Administrative/Chemical Building and the DAF Building are comprised of the majority of the these building's components (including lab equipment) coming due. 4P, BRWTF Renewal Forecast By Facility Q 5!n,mm.[rcnr SGq,n6 MD 5sn,utK1,[rcro 5.10,HOMO SAO OLK118111 ■ Flect nGdl ■ MAfh,3fiL31 Sw.010,01n1 510,000.000 1 ~ . S lllll1 ~p\ ~"3yS' 'IVC- S,G' r4\: - `C' 60g1 Ca SDF S`F ac~ o5d` 91~s c` t~+a° Lhys~ lell 1~ 4` 9,5 4o Qo V6 5` 33 Figure 8: BRWTF Renewal Forecast By Facility/Process F-14 4.2 Hydroelectric and PRV Facilities Figures 9 and 10 present renewal estimates for hydroelectric and PRV facilities. With the City, the decision was made that the analysis of these facilities would consider the facility and its assets at a higher level only and not drill down to a civil/mechanical/electrical analysis because the systems are generally less complex than a water treatment facility. These estimates total to about $11 M over 50 years, or a $200,000 average annual expenditure, as shown in Figure 9. Hydro & PRV 50-Year Renewal Forecast MWH COSINESS SOLUnONS C:ty of B-,. S4,000.000 S 1. SU0.UV0 51 pnn,noo S2,SU0.UW S 2,0WN', 51504.630 $1 f][NI,[N NI j r A.erage: $0.ZM per year $SOO.D00 v co v w c o v w c+ c ~ c+ o y w e Figure 9: Hydroelectric and PRV Facilities 50-Year Renewal Forecast Projected costs well above the annual average occur in the following years as analyzed below. • 2024: About two-thirds of these costs amounting to $1.3M is attributable to the turbine bypass valve at the Orodell facility. The turbine bypass valve at Kohler and the turbine/generator at Maxwell are significant costs as well at approximately $200,000 each. The difference in cost between the Orodell valve and the Kohler valve are that the Orodell valve has been rated as a "complex" project by the City, which is defined as needing help of a significant level external to the City to complete the project, thus adding additional cost. 2027: An investment need of $350,000 is identified for this year to renew Kohler's turbine/generator. 2029: Over half of the $600,000 slated for this year would be to renew Orodell's turbine/generator. 2030: The replacement cost of Sunshine's turbine generator amounts to $3.3M. Sunshine's turbine/generator is Boulder's most expensive one and would be a "complex" project. 2043: Structural work at Sunshine will amount to $300k and includes its retaining walls. F-15 2045: The altitude valves for the reservoir tank at Maxwell and the PRV valves at the 101 Pearl PRV Station will amount to $2.5M this year. • 2049: The costs of approximately $1.4M are attributable to the expiration of the Sunshine PRV vault. Hydro & PRV Renewal Forecast By Facility r"WH ($300k/yr. Avg.) 555~:.~,t~~s s tsoo,aao i1.UW,UW Si'W,UW i f,11INJ.UlN1 $I,StN),gW OM'OW S J.snn.0M S 1.UW.UW 5;00.60a ■ dl c~ a` a Ile rJ ~~Sr ¢y? O~ L Figure 10: Hydroelectric and PRV Facilities Renewal Forecast By Facility As shown in these figures, average repair and renewal costs for hydroelectric and PRV facilities are estimated at $0.2M per year, largely due to extensive repair or renewal needs throughout the Maxwell, Orodell, and Sunshine hydroelectric facilities. F-16 4.2 Treated Water Storage Facilities Figures 11 and 12 present repair and replacement estimates for the various treated water storage facilities. With the City, it was decided that the analysis of these facilities would consider the facility and its assets at a higher level only and not drill down to a civil/mechanical/electrical analysis because the systems are generally less complex than a water treatment facility. As shown in these figures, average repair and renewal costs for treated water storage facilities are estimated at $3.6M per year, or about $180M over 50 years. ~X✓ Water Storage 50-Year Renewal Forecast ® MwH TT 9L_i~JE555CLJTIDYS yu6 SSU.JLO.VOU - S80JCO 000 570.N.O.000 SO0.000.000 5:at,xn,oen S.u,xo.oeo s r.:n II.Ouu 52n.'lrn.n0(1 Av ra c: 3.6M Per ca, - ■ ■ ■ 1 _ ■ _ 4 o a v e _ u _ _ t, _ _ _ c, i v C-5 - Figure 11: Water Storage 50-Year Renewal Forecast Figure 11 shows spikes well above the annual average in the years discussed below: ■ 2016: The $8.9M renewal needs in 2016 mainly represent the roof structure at the Kohler reservoir. Kohler has a corrugated metal roof supported on a system of concrete, steel beams, and concrete columns. • 2046: Electrical and coating needs at Gunbarrel reservoir, electrical work at Booton reservoir, and sitework and electrical needs at Devil's Thumb reservoir comprise the $10M of improvements forecasted for 2046. 2047: Sitework, including yardpiping and related valves and vaults, is expected to expire at the Maxwell reservoir at a cost of $12M. • 2054: Replacement of the concrete tank at Maxwell reservoir represents a 2054 cost projected at $79M and $3M for electrical work at Chautauqua. The current condition rating of the tank is a "4", representing that at least 40% renewal of the tank is required presently. Maxwell's tank will need to be evaluated as to whether repair will serve as a suitable substitute for full replacement, especially in the area of the tank that is pushing out away from the rest of the tank. The evaluation required should be a complete structural evaluation and include evaluation of the structural components of the tank that can only F-17 be viewed from the inside where presently unviewable damage may or may not be present. If the structural evaluation pushes the condition rating to a "5", representing 90% renewal required, the tank will need to be repaired or replaced much sooner, likely the year of 2017 at a cost around $26.5M. Depending on the evaluated structural condition, repairs may potentially be possible to extend the life 15 to 20 years from the time of repair if it makes sense to buy time for other assets to be addressed instead of Maxwell's tank during this time. If the tank can be pulled offline for awhile, repairing the concrete lining on the bottom may be of great help to prevent seepage and also prolong the life of the tank. • 2056: Maxwell reservoir is projected to need approximately $9.1 M of miscellaneous mechanical renewal in 2056. • 2057: Booton reservoir's concrete tank and concrete valve vault are set to expire in 2057 at an estimated cost of $22M. Sitework at Kohler, which includes yardpiping and related vaults, is also expected to cost about $4.5M. 50-Year Water Storage Renewal Forecast By Facility MWH . . sioc.aaa,c:m . 580.000.000 560.0M ow 140.000,1ao sza.oao,ON- iyd+ p\ Jb1 J, O` 14•x9 van at'° Figure 12: Water Storage Renewal Forecast By Facility The high amounts shown in Figure 12 are largely attributed to Maxwell reservoir's renewal needs throughout the facility, including repair or replacement of its tank and its sitework, partially which may be required to stabilize the integrity of the tank. The majority of the costs at Booton are attributable to renewal of its tank. 4.4 Overall Results for BRWTF and the Stranded Facilities Based on the analysis performed on the presently available data provided, approximately $7.6M per year or $381 M over 50 years should be budgeted to ensure the sustainable repair and renewal of the BRWTF and stranded facilities: F-18 Table 4: Summary of BRWTF and Stranded Facilities Renewal Needs Asset Group Forecasted Need ($M/50yr.) Forecasted Need ($M/yr.) BRWTF 190 3.8 Hydroelectric/PRV 11 0.2 Storage Reservoirs 180 3.6 Totals 381 7.6 4.5 Valuation Analysis The City calculates asset value using an accounting or straight-line approach: Asset Value = Estimated Replacement Cost (new) - Depreciation Here, depreciation is calculated in a straight-line fashion based on the age and expected useful life for the asset. For example, a 5-year-old blower with a replacement cost of $20,000 and an expected useful life of 10 years would be valued at $10,000: (Replacement Cost - of life consumed)*Replacement Cost = Current Asset Value, or $20,000 - (5years/10years)*$20,000 = $10,000 This is the methodology built into both the Betasso WTP asset management pilot project and the three asset management workbooks (BRWTF, hydroelectric, tanks) developed as part of this Master Plan. In the future, the City may want to consider a more condition-based valuation methodology that takes the condition scores developed in this Master Plan into account and let that influence the expected useful life or the shape of the deterioration curve to make it more reflective of reality rather than a straight-line depreciation. For example, the blower described above may still have a condition score of 2 (good or assumed 10% useful life consumed) after five years. The resulting valuation would take this condition into account when calculating the asset value and expected useful life: Replacement Cost - (condition score fraction)* Replacement Cost = Current Asset Value, or $20,000 - (10%)"$20,000 = $18,000 Contrast this with a blower that is poorly maintained, and has a condition score or 5 (very poor, or assumed 90% useful life consumed): $20,000 - (90%)"$20,000 = $2,000 Thus, condition scores can be used to better understand the current value of the City's assets. 5.0 Conclusions and Recommendations With this project, the City has taken important first steps in enhancing its approach to asset management for the BRWTF and stranded facilities. Several of these achievements pertaining to these facilities are listed below: • Gap filling and reconciliation of the City's asset dataset, including updating of cost factors, the breakout detail and analysis of grouped improvements (i.e., "19XX Improvements") and breakout of valves from piping and yard piping from other sitework, refinement of the Hydro/PRV useful lives, and completion of asset original and/or replacement costs. This will help to add further refinement the forecasts. F-19 • Assigning initial consequence of failure scores an important first step to being able to develop risk scores and develop a risk-based renewal forecast that is more strategic. • Developing long term (50-year) renewal forecasts. • Constructing asset management workbooks for three facility categories. Based on this analysis of the BRWTF and stranded facilities, potential near-term enhancements to the City's existing asset management approach to consider include: • Migrating asset data into one database driven application for more robust asset management capabilities. • Establishing a data framework to have a clear asset hierarchy and asset registry. • Incorporating the consequence of failure analysis to enhance the condition-based analysis of this task to strive for an enhanced, risk-based asset renewal forecast. • Establishing business processes to enable and support ongoing enhanced asset management, regular updating of condition scores, and an overall asset management strategy. • Develop an ongoing, programmatic approach to asset management to drive asset strategy throughout the organization and realize benefits associated with more defensible renewal budgets and utility performance. A quality asset management program will have both planning and implementation components, build on existing efforts, staff knowledge, and tools, and reach across water, wastewater, stormwater and flood management vertical (i.e, facilities) and horizontal (i.e., pipes) assets. F-2o Table 4: Summary of BRWTF and Stranded Facilities Renewal Needs Asset Group Forecasted Need ($M/50yr.) Forecasted Need ($M/yr.) BRWTF 190 3.8 Hydroelectric/PRV 11 0.2 Storage Reservoirs 180 3.6 Totals 381 7.6 4.5 Valuation Analysis The City calculates asset value using an accounting or straight-line approach: Asset Value = Estimated Replacement Cost (new) - Depreciation Here, depreciation is calculated in a straight-line fashion based on the age and expected useful life for the asset. For example, a 5-year-old blower with a replacement cost of $20,000 and an expected useful life of 10 years would be valued at $10,000: (Replacement Cost - of life consumed)*Replacement Cost = Current Asset Value, or $20,000 - (5years/10years)*$20,000 = $10,000 This is the methodology built into both the Betasso WTP asset management pilot project and the three asset management workbooks (BRWTF, hydroelectric, tanks) developed as part of this Master Plan. In the future, the City may want to consider a more condition-based valuation methodology that takes the condition scores developed in this Master Plan into account and let that influence the expected useful life or the shape of the deterioration curve to make it more reflective of reality rather than a straight-line depreciation. For example, the blower described above may still have a condition score of 2 (good or assumed 10% useful life consumed) after five years. The resulting valuation would take this condition into account when calculating the asset value and expected useful life: Replacement Cost - (condition score fraction)* Replacement Cost = Current Asset Value, or $20,000 - (10%)"$20,000 = $18,000 Contrast this with a blower that is poorly maintained, and has a condition score or 5 (very poor, or assumed 90% useful life consumed): $20,000 - (90%)"$20,000 = $2,000 Thus, condition scores can be used to better understand the current value of the City's assets. 5.0 Conclusions and Recommendations With this project, the City has taken important first steps in enhancing its approach to asset management for the BRWTF and stranded facilities. Several of these achievements pertaining to these facilities are listed below: • Gap filling and reconciliation of the City's asset dataset, including updating of cost factors, the breakout detail and analysis of grouped improvements (i.e., "19XX Improvements") and breakout of valves from piping and yard piping from other sitework, refinement of the Hydro/PRV useful lives, and completion of asset original and/or replacement costs. This will help to add further refinement the forecasts. • Assigning initial consequence of failure scores an important first step to being able to develop risk scores and develop a risk-based renewal forecast that is more strategic. • Developing long term (50-year) renewal forecasts. • Constructing asset management workbooks for three facility categories. Based on this analysis of the BRWTF and stranded facilities, potential near-term enhancements to the City's existing asset management approach to consider include: • Migrating asset data into one database driven application for more robust asset management capabilities. • Establishing a data framework to have a clear asset hierarchy and asset registry. • Incorporating the consequence of failure analysis to enhance the condition-based analysis of this task to strive for an enhanced, risk-based asset renewal forecast. • Establishing business processes to enable and support ongoing enhanced asset management, regular updating of condition scores, and an overall asset management strategy. • Develop an ongoing, programmatic approach to asset management to drive asset strategy throughout the organization and realize benefits associated with more defensible renewal budgets and utility performance. A quality asset management program will have both planning and implementation components, build on existing efforts, staff knowledge, and tools, and reach across water, wastewater, stormwater and flood management vertical (i.e, facilities) and horizontal (i.e., pipes) assets. wWW.mwhgIobal. com 4 JkJ*A ~ r _ Appendix A: Scope of Work Water Utility Master Plan The Water Utility Master Plan (WMP) scope of work (SOW) and deliverable milestones have been organized around the draft WMP outline presented in MWH's proposal dated November 13, 2009 and subsequently discussed with City staff at the scope refinement meeting held on January S, 2010. The WMP volumes and sections referenced in the following SOW are taken from the outline which is included as Attachment 1 to this SOW. Task 1: Prepare Volume 1- Executive Summary The purpose of this task is to provide an executive summary of the information included in Volumes 2 through 6 of the Water Utility Master Plan (WMP). The executive summary will summarize the following information: • Planning information (Volume 2) • Water system overview (Volume 2) • Water Quality Strategic Plan (WASP) (Volume 3) • Source Water Master Plan (SWMP) (Volume 4) • Treated Water Master Plan (TWMP) (Volume 5) • Water Utility Capital Improvements Plan (Volume 6) Summary information for the WASP and SWMP will be taken from these recently completed documents (2009) while summary information for the TWMP will be taken from the update of this document being prepared as part of this SOW. Additionally, the executive summary will include a small section providing an introduction and document purpose statement as well as a section summarizing community and staff involvement in the development of the plan. Preparation of Volume 1 will occur after completion of Volumes 2 through 6. Task 2: Prepare Volume 2 - General Planning Information The purpose of this task is to provide a single volume of the general planning information that supports the three planning components of the overall WMP (WASP, SWMP, and TWMP). The general planning information includes the following items and subsections: • System History • System Overview/Inventory of physical facilities. • Summary of pertinent codes, ordinances, and policies 1 • Planning approach and assumptions • Definition of Study Area • Population and Employment Data • Land Use Data • Water Use Data MWH will develop these subsections in accordance with the following task descriptions. A draft version of Volume 2-General Planning Information will be completed prior to Workshop No. 1 to allow for review and discussion during this workshop (See Task 7.2 - Workshops). 2.1 System History Working with staff and using the system history from the previous master plans and the Water Quality Strategic Plan, MWH will update the history of Boulder's water system and planning objectives. 2.2 Overview/Physical System Inventory MWH will prepare an update of the inventory of the existing water facilities, particularly the treatment and distribution facilities. This will include a review of the dams and major source water pipelines from the Source Water Master Plan (SWMP), treatment facilities, pumping, hydroelectric, pressure regulating, storage, transmission and distribution. The inventory will consist of a summary of design data for major process units and equipment, at a basic level and in a consistent spreadsheet format, for general use in the planning and public review processes. A list and brief description of private water systems connected to the city's system will be prepared for reference, based on information provided by the city. 2.3 Code, Ordinances, and Policies Using the summary presented in previous and related master plans and any more recent policy information provided by the city, MWH will provide an updated summary of the city's pertinent ordinances, codes, service standards and policies from the city code, the Boulder Valley Comprehensive Plan, the City of Boulder Design and Construction Standards, the Utilities' Division Guiding Principles and other relevant documents provided by the city. 2.4 Planning Approach and Assumptions MWH will develop a summary of the planning approach and assumptions that are relevant and common to all three of the planning components based on review of the existing planning documents along with input from City staff. Additionally, MWH will summarize the process that will be used to develop the consolidated CIP. 2 2.5 Definition of Study Area The study area definition will be based on the GIS database information indicating water utility planning area boundaries. MWH will develop a description figure of the planning area. 2.6 Population and Employment/Land Use These sections will be based upon existing land use and population projections from the city's planning department as documented and presented in the recent wastewater utility master plan. Based on the city's 2009 Community Data Report, the population and employment projections included in the wastewater utility master plan were prepared in conjunction with Denver Regional Council of Governors (DRCOG) such that no additional review/development of information is needed. 2.7 Water Use The city will provide MWH with historical water usage rates for single family residential, multi- family residential, business, and "other" categories. Unless other figures are provided by staff, MWH will estimate future annual unit demands by reviewing projections in the Source Water Master Plan. Peak hour, peak day, and peak month demand factors will be based on review of previous TWMP factors and recent historic data. It is anticipated that ultimate determination of appropriate factors will require input from City staff. MWH will produce a summary of the projected average daily demands, peak day demands and peak hourly demand for the system in the years 2010 (current), 2015, 2020 and 2030. It is assumed that the land use and population distribution information and digital maps to be used in this task from the wastewater utility master plan are existing and up to date. This GIS data will be provided to MWH. MWH will apply the developed water usage rates for each land use category to the existing land use maps to show how water use would vary spatially for 2010 (current), 2015, 2020, and 2030. Task 3: Prepare Volume 3 - Water Quality Strategic Plan The purpose of this task is to prepare the existing WASP for incorporation as Volume 3 of the WMP. Based on discussions with City staff, this task will consist solely of providing new cover sheets for the document indicating it as Volume 3 of the WMP. Task 4: Prepare Volume 4 - Source Water Master Plan The purpose of this task is to prepare the existing SWMP for incorporation as Volume 4 of the WMP. Based on discussions with City staff, this task will consist solely of providing new cover sheets for the document indicating it as Volume 4 of the WMP. 3 Task 5: Prepare Volume 5 -Treated Water Master Plan The purpose of this task is to prepare an update to the existing TWMP for incorporation as Volume 5 of the WMP. The updated TWMP will consist of the following items and subsections: • Treated Water System Description • Water Quality • Water Quality Regulations and Goals • Summary of Recent Treatment Facility Studies Conclusions and Recommendations • Water Treatment Plant Evaluation • Residuals Management Plan • Distribution System Evaluation • Asset Management • Issues • Common Recommendations • Water Treatment Plant Recommendations • Distribution System Recommendations MWH will develop these items and report subsections in accordance with the following task descriptions.. A draft version of Volume 5 - Treated Water Master Plan will be completed prior to Workshop No. 2 to allow for review and discussion during this workshop (See Task 7.2 - Workshops). 5.1 Treated Water System Description MWH will update the existing TWMP treated water system description with improvements and system changes that have occurred in the intervening period to bring the description up to date. Improvement and system change information will be provided to MWH by the City in the form of annual reports, design reports, and staff survey information. 5.2Water Quality, Regulations, and Treated Water Goals Information generated from this task will consist of a water quality summary, a comparison of historical treatment facility performance with water quality standards and City established treatment goals, and an update of drinking water regulatory requirements. The city will provide MWH with a spreadsheet of raw and finished water quality data for each water treatment facility. The city will also provide a spreadsheet of available distribution system water quality data. MWH will summarize the raw and treated water quality data using percentiles and will compare that information to the city's existing treatment and operational 4 performance criteria. For parameters that are not meeting the city's goals or water quality standards, and for parameters of concern (e.g., TOC, DBPs, taste & odor), MWH will perform additional analysis to determine seasonal or other trends in the water quality data. The water quality summary and comparison to the performance criteria will be presented to staff for discussion and finalization in the first consensus building workshop. MWH will also provide an update of relevant drinking water regulations and system service standards. The water quality summary and comparison to performance criteria along with a bulleted list of findings will be provided to staff. It is assumed that city staff will provide water quality data in spreadsheet format, organized in terms of the performance criteria; for ease of analysis by MWH. 5.3 Summary of Recent Treatment Facility Studies Conclusions and Recommendations MWH will review recent treatment facility studies, including information in the Vulnerability Assessment related to the Boulder Reservoir and Betasso WTPs, and will summarize relevant and appropriate conclusions and recommendations made to carry forward into the treatment plant evaluation section. Improvement recommendations from the vulnerability assessments will only be generalized in any of the WMP documents. 5.4 Water Treatment Plant Evaluations MWH will evaluate the performance and needs of the Betasso and Boulder Reservoir Water Treatment facilities. Evaluation will consist of the following: • Assessment of physical condition and reliability of the facilities based on previous condition assessment information, limited scope on-site inspections, and interviews with City staff • Summarize and confirm the hydraulic capacity of the plants, based on information provided by city staff • Determine the treatment capacity of the plants under current and proposed required treatment standards • Determine methods to optimize hydraulic and treatment capabilities including the limiting unit process. • Evaluate chemical and energy consumption patterns for efficiency and cost effectiveness. This analysis will be limited to major process consumers. • Review Betasso residuals management study prepared by Carollo Engineers and make residuals management recommendations based on updated TWMP demand projections. 5 • Review staffing, 0&M procedures and concerns and maintenance programs. The information for this analysis will be provided by the city in the form of documentation and feedback from staff interviews. These staff interviews will be conducted by MWH and be in addition to feedback provided in the workshops. • Identify facility upgrades and operational procedures needed to assure continued water quality compliance with drinking water regulations and service standards including relevant and appropriate recommendations from previous studies summarized in Task 5.3. • Identify potential future water quality issues based on treatment facility capacity, historical performance, and projected future flow conditions 5.5 Additional Investigations MWH will perform additional investigations, studies, and engineering services at the direction of the City's Project Manager to refine or further develop concepts, issues, or solutions identified in the master planning work. The work will be scoped and budgeted not to exceed the fee amount allocated forthis task in Appendix C of the Agreement. 5.6 Distribution System Evaluations MWH will evaluate the condition and reliability of the existing treated water distribution system including pumping, storage, hydroelectric, pressure regulating, transmission, distribution, and monitoring and control. Evaluation of the condition of the distribution system below grade piping, valves, and appurtenances ("horizontal" assets) will be based on existing condition assessment information provided by the City. MWH will also incorporate relevant and appropriate conclusions or recommended distribution system projects from the Vulnerability Assessment into the distribution system evaluation. A small number of stranded facility "vertical" assets within the system will be evaluated through detailed facility inspections as described in Task 5.6.10. A large component of the distribution system evaluation will be accomplished using the existing distribution system model. MWH will confirm calibration of the distribution system hydraulic model, by reviewing previous calibration results but assumes that no significant recalibration efforts will be required. The distribution system evaluations will include the following subtasks: 5.6.1 Operations and Maintenance Data Review This subtask will include a review of staffing, operations and maintenance (O&M) procedures and concerns and maintenance programs. The information for this analysis will be provided by the city in the form of documentation and feedback from staff interviews. These staff interviews will be conducted by MWH and be in addition to feedback provided in the 6 workshops. MWH will review relevant data provided by the city and evaluate operation and maintenance indicators such as main breaks, flushing, customer complaint calls. 5.6.2 Hydraulic Capacity Evaluation MWH will use the distribution system hydraulic model to evaluate the system capacity based upon the new demand conditions and planned service area growth patterns. The model will be used to determine improvements required to meet the new demand conditions. 5.6.3 Fire Flow Analysis MWH will use the distribution system model to analyze the system for adequate fire flow capacity. 5.6.4 System Storage Analysis MWH will use the distribution model to evaluate system storage in all pressure zones for rehabilitation needs and additional storage requirements, particularly in zone 1. 5.6.5 Additional Pressure Zone Analysis MWH will work with city staff to determine the need for additional pressure zones within zones 2 and 3, and define those sub-zone boundaries, if they are necessary, by establishing pressure criteria for the system. MWH will use the distribution model to review the existing pressure zone boundaries and operating conditions, define and simulate potential additional pressure zones, and recommend improvements. Planning level costs will be developed for any recommended improvements. 5.6.6 Water Quality Analysis MWH will use the distribution system model to evaluate up to five operational scenarios and facility improvements to optimize water quality and maintain consistent chlorine residual throughout the distribution system and minimize detention time in the system. 5.6.7 System Component Failure Analysis MWH will review previous reports regarding system component failure analysis and provide input to the City regarding component failure mitigation strategies. MWH will model up to five alternative distribution system operating scenarios selected by the City to analyze failure operations and mitigation strategies. Additionally, MWH will review the City's established reliability criteria to determine if they can be met under the future demand scenarios. 5.6.8 Distribution System Modeling Workshop 7 MWH will conduct a one-day workshop with city staff and MWH modeling and distribution experts, to run model simulations of and refine proposed distribution system improvements identified in this task. 5.6.9 System Monitoring Evaluation MWH will review the existing SCADA system for potential improvements. This task will consist of reviewing SCADA screens and monitoring points, control philosophies, current and anticipated regulatory requirements, and industry trends. There will be a focus on potential operational efficiency/cost-savings through increasing automation and monitoring within the system, and MWH will provide general recommendations for future SCADA system hardware and software upgrades to meet the city's goals. 5.6.10 Stranded Facility Inspections MWH will perform facility inspections for condition assessment of the following stranded facilities: • 101 Pearl PRV facility • Sunshine, Orodell, Maxwell and Kohler hydroelectric facilities • Gunbarrel, Maxwell, Booton, Devils Thumb, Kohler, and Chautauqua reservoirs MWH anticipates using structural and hydroelectric discipline engineers to perform these inspections. MWH has assumed that the inspections will consist of a one day site visit for the hydroelectric facilities and a one day site visit for the storage reservoirs. The inspections will also consist of review of engineering information provided by the city for each of the facilities, and preparation of a brief summary of findings along with a filled out condition assessment form consistent with current city practice and asset management recommendations developed as a part of Task 5.7. 5.7 BRWTP and Stranded Facilities Asset Management Update MWH will evaluate, refine, and update the replacement cost estimates of facility assets (e.g., equipment, structures) at the Boulder Reservoir Water Treatment Plant (BRWTP) and stranded facilities identified in subtask 5.6.9 above to allow the City to better estimate the overall renewal and replacement Capital Improvement Program (CIP) and maintenance budgets. Additionally, MWH will make recommendations to improve the City's overall asset management program. The following subtasks and sub-activities are included in this task: • Analysis of Asset Valuation Methodologies • Asset Data Review, Analysis, and Replacement Cost Calculations 8 o Data Compilation and Gap Filling o Asset Condition Workshop o Asset Expected Remaining Life and Replacement Cost Estimates • Document Asset Valuation Findings in a draft technical memorandum with final document contents incorporated in the TWMP All work will be consistent with the approach and techniques used for developing the Betasso WTP asset management system that has been provided to MWH by the City except as specifically noted below. 5.7.2 Analysis of Asset Valuation Methodologies The purpose of this subtask is to define the asset hierarchy and valuation approach to be used in determination of the facility asset values. MWH will perform the following activities: • Compilation and review of available asset data; • Identification and compilation of asset categories; and • Document existing City standards of value, valuation approaches, and calculation options. The initial review of Boulder Reservoir WTP asset types will employ readily available data to produce an inventory of Boulder Reservoir WTP's asset base. Boulder Reservoir WTP's CMMS, spreadsheets, financial system, historical data and other sources will be used to construct the inventory. The assets will be mapped into asset categories. Typical asset categories include system (ex: WTP), sub-system (ex: process area) and assets (ex: structural, mechanical, and electrical assets). Deliverables for this subtask include • Asset Hierarchy • Asset Valuation Approach 5.7.3 Asset Data Review, Analysis, and Replacement Cost Calculations This subtask will perform a detailed assessment and valuation of the Boulder Reservoir WTP asset base. MWH activities to deliver this scope are expected to include the following: Activity 1: Data Compilation and "gap filling" MWH will perform an asset data assessment related to the Boulder Reservoir WTP and stranded facility assets. This effort will determine the quality, quantity, accuracy, accessibility and reliability of asset information including primary asset attributes (location, material, size, 9 capacity and installed date) and secondary asset attributes (condition, failure history, cost history, maintenance history) held in City databases or spreadsheets. MWH will perform this assessment through workshops and discussions with City staff as well as a review of readily available information sources. MWH will compile the available asset data, assess key data gaps as related to the condition scoring efforts, and propose potential solutions to the City to fill the data gaps as part of the condition scoring efforts, where appropriate. This task is not intended to include field work (e.g., asset inspections or condition tests), otherthan that conducted as part of tasks 5.4 and 5.6.10, or extensive data gathering from raw paper or electronic sources (e.g., through examination of record drawings or individual work order reports). The review of existing data sources will be for the most part limited to digital data which are readily extractable into a usable format for analysis within the systems such as the CMMS, financial system, cost database, etc. Activity 2: Asset Condition Workshop MWH will develop probability of failure scores for the major asset and asset group as developed in Task 2 through an examination of the available data and through workshops with City staff. MWH will hold up to a total of two (2) workshops with experienced City operations, field, and technical staff to determine the existing condition, probability of failure, and historical / expected failure modes of Boulder Reservoir WTP plant assets. These workshops are anticipated to last approximately three hours each. MWH will compile the results from these workshops and review the available data sources related to asset probability of failure. Where specific field-based data on asset condition and performance are not available (e.g., age, material, capacity, horse power), an initial condition score will be assigned based on City staff knowledge, available work order information, and known or assumed age and manufacturer data. Where assumptions are made to develop condition scores (e.g., filling data gaps related to asset age or capacity), these assumptions will be documented. Activity 3: Asset Expected Remaining Life and Replacement Cost Estimates Asset expected remaining life and replacement costs will be estimated from data from Activities 1 and 2 above, original and current construction costs estimates per asset type, experiences of City staff, MWH experience on other similar projects, and in accordance with the guidelines of the AACE for Class 4 estimate. Deliverables for this subtask include: • Updated Asset Inventory Spreadsheet/Database • Asset Condition Score • Asset Expected Remaining useful life and Replacement Cost 10 5.7.4 BRWTP Site Plan Yard Piping and Conduit Asset Management Drawing Development MWH will update existing 2D drawings of yard piping and conduit duct banks for the Boulder Reservoir WTP site using existing WTP site plan drawings as developed for the Near and Mid- Term Improvement projects with incorporation of additional piping and conduit duct bank information of record provided by the City. It is anticipated that only minor additions of piping and conduit duct banks will be required to fully update the existing site plan yard piping and conduit duct bank drawings. After additions of yard piping and conduit duct banks are complete, MWH will develop the asset management drawing by incorporation of the following: 1. Addition of callouts for the pipe material/size/fluid information as required. 2. Addition of asset tags for each segment per pipe. A segment will be defined as pipe length between a change in alignment/direction/size or between structures (i.e. manhole or vault) or appurtenances (valves, tees, etc.). MWH has assumed that dividing the site plan into four yard piping/conduit drawings will provide an appropriate scale for the asset management drawings. 5.7.5 Valuation Documentation MWH will prepare a draft Technical Memorandum for review by City staff. MWH will also provide updated asset spreadsheet/database with revised cost and cost basis for each asset along with the BRWTP asset management drawings developed in subtask 5.7.3 above. Final versions of the draft memorandum, updated asset spreadsheets, and BRWTP asset management drawings will be incorporated into the TWMP. Deliverables for this task include: • Technical Memorandum on cost estimate methodology, assumptions, and calculations • Updated Asset Inventory Spreadsheet/Database 5.8 Development and Summary of TWMP Recommendations and Conclusions From the work completed during tasks 5.1 through 5.7, MWH will develop a summary of recommended deficiency corrections and improvements for the existing treatment and distribution systems including a comparison of results to existing water quality, pressure, quantity, and reliability service standards. MWH will also develop budgetary costs for these items that will be incorporated into the CIP prioritization process included in Task 6. Task 6: Prepare Volume 6 - Water Utility Capital Improvements Plan The purpose of this task is to prepare a consolidated prioritized capital improvements plan (CIP) from the CIP recommendations included in the WASP, SWMP, and TWMP for presentation in 11 Volume 6- Water Utility Capital Improvements Plan of the WMP. Development of the consolidated CIP will consist of the following items and subsections: • Consolidated CIP Development Approach • Budgeting Process and Current Fiscal Constraints • Categorization and Prioritization of Projects • Water Utility Capital Improvements Plan MWH will develop these items and report subsections in accordance with the following task descriptions. A draft version of Volume 6 - Treated Water Master Plan will be completed prior to Workshop No. 3 to allow for review and discussion during this workshop (See Task 7.2 - Workshops). 6.1 Consolidated CIP Development Approach MWH will summarize the approach used to develop the consolidated prioritized water utility CIP. 6.2 Budgeting Process and Current Fiscal Constraints MWH will summarize the City's budgeting process and current fiscal constraints from information provided by the City. 6.3 Categorization and Prioritization of Projects As part of this task, MWH will prepare a consolidated list of capital improvements from the WASP, SWMP, and TWMP for review at Workshop No. 2 (See Task 7.2 - Workshops). With input from City staff and stakeholders obtained from Workshop No. 2, CIP prioritization criteria and weighting factors will be developed and the consolidated list of recommended improvements will be broken down into the following categories: • 'Fiscally Constrained' Minimum, Essential Required System Needs: Identify existing deficiencies and replacements for capital facilities needed to continue to provide existing service defined by the service standards and regulations. This is a prioritized, refocused service plan within existing budget targets. • Action Plan for Growth Related System Needs: Capital facilities necessitated by new residential or nonresidential growth. This includes funding needed to provide community wide improvements to meet the needs of new growth. These improvements are desirable, or necessary, if we intend to bring the systems up to the level needed to provide our service standard to development proposed in long term planning and zoning. 12 • Vision Plan for Water System Enhancements: Capital facilities needed to provide increased level of service desired by the community. This 'Vision Plan' level of operational and capital improvement that is discretionary along with alternative proposals to fund them. The consolidated list broken down into these three general categories will then be used in Workshop No. 3 (See Task 7.2 - Workshops) with City staff to prioritize and rank each CIP project using the Criterium Decision Plus model developed for this project. 6.4 Water Utility Capital Improvements Plan MWH will summarize the results of Task 6.3 and Workshop No. 3 to develop the final recommended consolidated Water Utility CIP for inclusion in the WMP. Task 7: Consensus Building Workshops and Staff Survey MWH will conduct a series of three one-day workshops throughout the WMP development process to support the preparation of a system-wide operational and capital improvement program and budget based upon the needed improvements and priorities. These workshops will be designed to gather feedback from city staff; confirm the methodology, criteria and weightings for evaluation of capital improvement projects; and develop and prioritize the system-wide operational and capital improvement program. Additionally, MWH will review the results of the Water Utility survey that was recently conducted in cooperation with AWWA and follow up with staff as appropriate to solicit additional feedback and input regarding business processes, needs, and potential efficiency improvements to be included in the WMP. These two processes are expected to maximize stakeholder input, promote staff acceptance of the final WMP, and increase the transparency of the decision-making process. 7.1 Workshop Preparation MWH project staff will prepare technical information and documentation required to support the consensus building workshops. As part of this task, MWH will prepare and test the Criterium Decision Plus model for use in Workshop #3. 7.2 Workshops Workshop #1 will gather input from City staff on the draft version of Volume 2 - General Planning Information as well as the WMP CIP prioritization methodology. The technical input to Workshop #2 will consist of the draft TWMP update and a proposed list of projects (not prioritized) to be included in the CIP. Workshop #2 will confirm the project list and establish the evaluation criteria and weightings to be used in the prioritization process. The 13 information generated in Workshop #2 will be used to prepare the 1st Draft WMP for review by city water utility staff. Workshop #3 will focus on prioritization of projects in the CIP list. MWH will use the Criterium Decision Plus software to initially rank projects with respect to the city's evaluation criteria and weightings. The results will be analyzed during the workshop, sensitivity analyses performed, and criteria or weightings revised in order to achieve consensus of the project prioritization. Comments from Workshop # 3 will be incorporated into the 2nd Draft WMP. 7.3 Workshop Follow-up MWH will document the results of each workshop and conduct follow-up activities identified in the workshops to address city concerns. 7.4 Staff Survey Review and Follow-Up MWH will review the results of the Water Utility survey that was recently conducted in cooperation with AWWA. The results will be analyzed with respect to developing additional recommendations on Water Utility business processes, needs, and potential efficiency improvements. MWH will follow up with individual staff and/or prepare a focused follow up questionnaire for areas that may need further feedback, as determined by the city project manager with input from MWH. Responses will be kept anonymous to city staff. MWH will present the information back the city in Workshop No. 2. The review analysis and additional survey feedback will be used in the development of capital and operational improvement recommendations in the "non-prioritized" project list developed as a part of Task 6.3 that will form the basis of the consolidated CIP. Task 8: Public Process The City of Boulder is committed to public involvement and community acceptance of this Water Utility Master Plan. The public process will: • Inform the public of Master Plan Update and their opportunity to participate using public notices in the newspapers and other media. • Allow the forum for public participation in this master plan and educate interested customers in the master plan development process and uses. • Identify issues of concern to the public for inclusion in the master plan. • Lead to approval of the plan by the Water Resources Advisory Board, the Planning Board and to final adoption of the plan by the City Council. To accomplish this task, city staff may have to form a focus group and hold a public meeting to present the master planning process and solicit further input from the public through a Focus 14 Group. If this is required, MWH assumes city staff will identify an initial group of stakeholders to form the Focus Group and will coordinate agendas and meeting logistics. MWH will tailor relevant deliverables and summaries from Tasks 1 - 7 such that they can be easily modified by City staff for presentation to the Focus Group if necessary. MWH will attend and guide a public presentation at the Water Resources Advisory Board meeting. MWH will make one presentation of the revised Draft WMP, as required, to each of the Water Resources Advisory Board, the Planning Board and the City Council to facilitate adoption of the plan. Task 9: Project Administration 9.1 Project Management Meetings The MWH project manager will conduct regular conference calls with the city project manager to discuss progress, budget and schedule issues. As appropriate, the MWH project manager will also use project meetings to discuss these issues with the city project manager. The action items from these calls/meetings will be documented and used to improve project performance. 9.2 Project Administration MWH will prepare a project execution plan, monthly invoicing, project close-out, and conduct general project administration activities in support of this project. 9.3 QA QC MWH will perform internal quality assurance/quality control reviews and checks on draf and final deliverable to the City. Depending on the actual project schedule, draft deliverable reviews may be performed concurrently with City reviews. Additional Scope of Work Assumptions and Clarifications 1. The Water Utility Master Plan must be reviewed, revised as necessary, accepted and adopted by the City Council. The following project milestone table indicates the assumed deliverable breakdown and review schedule for the components of the WMP. Proposed Milestone Date Notice to Proceed 1-Mar Completed Report Outline 15-Mar Draft Volume 2 (General Planning Information) 15-Apr Asset Management Workshop #1 15-Apr Volumes 3 (WASP) and 4 (SWMP) Completed 30-Apr Consensus Building Workshop #1 (Planning Info review, CIP 30-Apr 15 prioritization methodology) Asset Management Workshop #2 30-May Distribution System Modeling Workshop 15-Jun Draft Asset Management TM 30-Jun Draft Volume 5 (TWMP) and Draft List of Capital Improvements 30-Jul Volume 2 Completed 30-Jul Consensus Building Workshop #2 (TWMP review, CIP prioritization criteria & weighting) 15-Aug Volume 5 (TWMP) Completed 15-Sep 1st Draft Volumes 1 (Executive Summary) and 6 (CIP) 15-Sep Consensus Building Workshop #3 (CIP Prioritization) 1-Oct Final Draft WMP (all volumes) 1-Nov Water Resources Advisory Board Review Jan -Feb 2011 Planning Board Review Mar 2011 Adoption of WMP by City Council Apr 2011 2. MWH assumes that all city comments and public process input received during the document review process will be reviewed and consolidated by the city project manager prior to review and response/incorporation by MWH. 3. Cost opinions included in this scope of work will be conceptual level engineer's opinion of cost. MWH will prepare the opinions and will not utilize an outside contractor. The conceptual level cost opinions to be developed under this scope of work will be prepared in accordance with the cost estimate classes defined by the Association for the Advancement of Cost Engineering (AACE) and will be "Class 4" for asset replacement cost estimates or "Class 5" level for CIP related estimates. 16 Attachment 1 Proposed Outline for Boulder Water Utility Master Plan Volume 1 Water Utility Master Plan Executive Summary 1.1 Purpose 1.2 Planning Information 1.3 Water System Overview 1.4 Water Quality Strategic Plan Summary 1.5 Source Water Master Plan Summary 1.6 Treated Water Master Plan Summary 1.7 Community and Staff Involvement 1.8 Development of Water Utility Capital Improvements Plan Volume 2 General Planning Information 2.1 Water System History Update 2.2 Water System Overview 2.3 Codes, Ordinances, and Policies 2.4 Planning Approach and Assumptions 2.5 Study Area 2.6 Population and Employment 2.7 Land Use 2.8 Water Use Volume 3 Water Quality Strategic Plan 3.1 Introduction 3.2 The Boulder Creek Watershed 3.3 Water Quality Trends and Challenges 3.4 Boulder's Water Quality Goals 3.5 Strategic Plan Recommendations and Performance Measures 3.6 Investment Program 3.7 Next Steps Volume 4 Source Water Master Plan 4.1 Introduction 4.2 Purpose and Scope 4.3 Management of Boulder's Water Supply 4.4 Raw Water Supply System Assets 4.5 Water Use, Availability, and Quality 4.6 Issues 4.7 Recommendations Volume 5 Treated Water Master Plan Update 5.1 Treated Water System 5.2 Water Quality 5.3 Water Quality Regulations and Goals 5.4 Relevant Recent Studies and Conclusions 5.5 Water Treatment Plant Evaluation 5.6 Distribution System Evaluation 5.7 Staffing, Operation and Maintenance Page 1 of 2 5.8 Issues 5.9 Common Recommendations 5.10 Water Treatment Plant Recommendations 5.11 Distribution System Recommendations Volume 6 Water Utility Capital Improvements Plan 6.1 Consolidated CIP Development Approach 6.2 Budgeting Process and Current Fiscal Constraints 6.3 Categorization and Prioritization of Projects 6.4 Water Utility Capital Improvements Plan Page 2 of 2