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HomeMy WebLinkAbout8.17.15 WRAB Complete PacketWATER RESOURCES ADVISORY BOARD MEETING MEETING DATE: Monday, 17 August 2015 MEETING TIME: 7:00 p.m. MEETING LOCATION: Municipal Services Center, 5050 E. Pearl St., Boulder, CO 80301 Agenda Highlights: 1. Call to Order (7:00 p.m.) 2. Approval of July 20 Meeting Minutes (7:01 p.m.) 3. *Public Comment (7:05 p.m.) 4. Information Item – Treated Water Distribution Monitoring (7:15 p.m.) 5. Matters From Board (7:45 p.m.) 6. Matters From Staff (7:50 p.m.)  Update on Wastewater Collection System Master Plan and Stormwater Collection System Master Plan 7. Future Schedule (8:20 p.m.) 8. Adjournment (8:30 p.m.) * Public Comment Item Agenda item times are approximate. Information:  Please contact the WRAB Secretary email group at: WRABSecretary@bouldercolorado.gov  Packets are available on-line at: http://www.bouldercolorado.gov – A to Z, Water Resources Advisory Board (WRAB), Next Water Resources Advisory Board Meeting WRAB Minutes 20 July 2015 Page No. 1 CITY OF BOULDER, COLORADO BOARDS AND COMMISSIONS MEETING MINUTES Name of Board / Commission: Water Resources Advisory Board Date of Meeting: 20 July 2015 Contact Information of Person Preparing Minutes: Rene Lopez 303-413-7149 Board Members Present: Vicki Scharnhorst, Lesley Smith, Ed Clancy, Dan Johnson Board Members Absent: Mark Squillace Staff Present: Jeff Arthur, Director of Public Works for Utilities Bret Linenfelser, Water Quality Environmental Services Manager Chris Douville, Wastewater Treatment Manager Michelle Wind, Drinking Water Program Supervisor Christin Shepherd, Civil Engineer 1, Floodways and Greenways Annie Noble, Acting Principal Engineer for Flood and Greenways Douglas Sullivan, Acting Principal Engineer for Water, Wastewater and Stormwater Cole Sigmon, Wastewater Process Optimization Specialist Rene Lopez, Board Secretary Meeting Type: Regular Agenda Item 1 – Call to Order [7:00 p.m.] Agenda Item 2 – Approval of the 27 April, 18 May & 22 June 2015 Meeting Minutes [7:01 p.m.] Motion to approve minutes from 27 April 2015 as presented. Moved by: Johnson Seconded by: Clancy Vote: 3:0 Motion to approve minutes from 18 May 2015 as presented: Remove a typing error on agenda item 4 for approval. Moved by: Johnson Seconded by: Clancy Vote: 3:0 Motion to approve minutes from 22 June 2015 as presented: Remove a typing error on agenda item 4 for approval. Moved by: Smith Seconded by: Clancy Vote: 3:0 Agenda Item 3 – Public Participation and Comment [7:06 p.m.] Public Comment: None Information Item 4 – Pre and Post Fire Watershed Planning [7:06 p.m.] Michelle Wind presented the item to the board. Executive Summary from the Packet Materials: The purpose of this memorandum is to update the Water Resources Advisory Board (WRAB) on the city’s proactive efforts for pre- and post-wildfire planning, specifically related to protecting the city’s water supply resources. Staff is not requesting any WRAB action at this time. WRAB Discussion Included:  Discussions about Phase 1 conclusions, which areas are a higher priority in the watershed.  Comments inquiring about the accuracy of the debris flow analysis with regard to actual debris flows.  Discussions about CU’s mountain research station, in the watershed, and that their involvement might be beneficial.  Comments regarding partnerships with other agencies such as the USGS and State Forest service, and Boulder County. Information Item 5 - [7:37 p.m.] Wastewater Treatment Update Chris Douville and Douglas Sullivan and other utilities staff presented the item to the board. Executive Summary from the Packet Materials: WRAB Minutes 20 July 2015 Page No. 2 This information item provides an update on the wastewater treatment facility (WWTF) and related programs / projects. The memorandum is organized as follows: 1. Summary of facility status and recent performance 2. Nitrogen Upgrades Project 3. Other noteworthy Capital Improvement Project (CIP) efforts WRAB Discussion Included:  Discussion regarding de-nitrification plans and their potential air quality impacts.  Comments regarding “rag” use for the IBM lift station project. Infiltration inflow problems. Working with IBM to source different “rag” materials. Using pumps that can get the “rag” materials to the 75th treatment facility.  Comments regarding the head works screens repaired during the 2013 flood, manufacturer repaired them under warranty.  Comments on infiltration mitigation costs, permit requirements and increased MGD due to sustained high water table, post flood event.  Discussions regarding flow monitoring data with regards to infiltration inflow data over the next 20 years. Agenda Item 6 – Matters from Board: [8:23 p.m.] 1. Johnson – Kossler Construction Update  Costly and delayed due to rain. Three weeks out. Significant change order to the project. - Ground water issue in Frasier  Issues have leveled out over the last 2 months. 2. Smith – CU student interview request for class project – Smith was interviewed by the student about water resources issues. - Article about Colorado Water Plan and potential Yampa Pumpback project – discussions of who would pay for it if Northern lead or input possible for WRAB?  Project input would be from new users of the system. 2. Clancy - Impacts with construction on 55th, Google campus – causing any sewer problems?  Capacity for collections reviewed by planning and development services  One section of pipe may need to be upsized in area called “Frontier” north or Pearl Pkwy, deferred at this time. Agenda Item 7 - Matters from Staff: [8:27 p.m.] Shepherd  Flood Mitigation Benefit-Cost Analysis Methodology  Discussions regarding data used in FEMA models  HAZUS tool may have been replaced by BCA tool.  Cost Benefit analysis greater than 1.0, higher the cost benefit, better chance of getting funding from FEMA.  Discussions regarding the increase in BCR benefits having to account for the first floor uses of building, how many people it services, nearby critical facilities, and other inputs to rate the benefit.  Discussions about using this model for the City’s assessments, and if this model provides good data.  Tool used primarily for eligibility for FEMA funding Arthur  Summer water usage is lower than projected numbers  Water main breaks  Upcoming City Council items  WRAB recruitment has opened to fill vacancy. WRAB Minutes 20 July 2015 Page No. 3 Agenda Item 8 – Future Schedule [8:56 p.m.] Upcoming meetings will consist of information items such as the following:  August – tour of the MSC facility o 6:00pm tour start time with dinner included; 7:00 meeting time as scheduled.  Next several meetings will have informational items  Flood studies check in’s coming Adjournment [9:00 p.m.] There being no further business to come before the Board at this time, by motion regularly adopted, t he meeting was adjourned at 9:00 p.m. Motion to adjourn by: Clancy Seconded by: Smith Motion Passes 4:0 Date, Time, and Location of Next Meeting: The next WRAB meeting will be Monday, 17 August 2015 at 7:00 p.m., at the City's Municipal Services Center, 5050 East Pearl St., Boulder, CO 80301 APPROVED BY: ATTESTED BY: _______________________________ __________________________________ Board Chair Board Secretary _____________________________ ___________________________________ Date Date An audio recording of the full meeting for which these minutes are a summary, is available on the Water Resources Advisory Board web page. https://bouldercolorado.gov/boards-commissions/water-resources-advisory-board-next-meeting-agenda-and-packet C I T Y O F B O U L D E R WATER RESOURCES ADVISORY BOARD AGENDA ITEM MEETING DATE: August 17, 2015 AGENDA TITLE: Information Item – Treated Water Distribution System Monitoring PRESENTERS: Jeff Arthur, Director of Public Works for Utilities Bret Linenfelser, Water Quality and Environmental Services Manager Michelle Wind, Drinking Water Program Supervisor Suzanne Givler, Water Quality Engineer EXECUTIVE SUMMARY The purpose of this Information Item is to update the Water Resources Advisory Board (WRAB) on the city’s proactive efforts for treated water distribution system water quality monitoring and tools for optimizing water quality in the distribution system. Staff is not requesting any WRAB action at this time, but the item is intended to inform future recommendations including the capital improvements program. BACKGROUND The city’s treated water distribution system begins at the two water treatment facility discharge points and includes: six storage facilities; three pressure zones; five inter-zone connections; multiple pumps and pressure reducing valves; four hydroelectric generators; and 454 miles of water mains. The distribution system is gravity-fed from the Betasso Water Treatment Facility. Water produced at the Boulder Reservoir Water Treatment Facility is pumped into the system. Historically, water quality research and regulations have focused on source water protection and water treatment, but in recent years, emphasis has expanded into the distribution system. Because of the size and complexity of the distribution system, maintaining the physical infrastructure is a continuous task, as is maintaining continuous water delivery to customers, ensuring adequate fire flow, maintaining water pressure, and ensuring optimal water quality. Distribution System Priority Developments In 2006, the National Academy of Sciences (NAS) released a report from a study that had been requested by the EPA on water quality issues associated with public water supply distribution systems. The report identified seven issues most relevant to protecting public health and maintaining the integrity of drinking water system distribution systems: Information Item #4 Page: 1 1. Cross connections and backflow of contaminated water 2. Contamination due to storage facility design, operation, or maintenance 3. Contamination due to main installation, repair, or rehabilitation practices 4. Contaminant intrusion due to pressure conditions and physical gaps in distribution system infrastructure 5. Significance and control of biofilm and microbial growth 6. Nitrification issues that lead to public health effects 7. Accumulation and release of contaminants from distribution system scales and sediments The report also focused on risk characterization and identified optimizing metrics related to physical, hydraulic, and water quality integrity. A subsequent 2010 EPA report identified and prioritized related research and information collection needs, with the goal that completed research would support future drinking water community risk management decisions including guidance, best management practices, regulations, and additional research needs. The American Water Works Association (AWWA) revised ANSI/AWWA Standard G200-09, Distribution Systems Operation and Management, also in 2010. The Water Research Foundation formed a new focus area in 2015 to define attributes and demonstrate benefits of intelligent distribution systems. The EPA is considering how distribution water quality can continue to be addressed during rule revisions as well as via non-regulatory channels, and is considering a Distribution System Rule. Regulations Affecting the Distribution System Federal and state drinking water regulations to date, in general, have focused more on treatment facilities than on distribution systems. Currently, monitoring requirements focused on distribution system water quality include monthly bacterial and disinfectant residual monitoring (TCR), quarterly disinfection byproduct monitoring (DBP), semi-annual lead and copper water quality parameters monitoring, tri-annual lead and copper monitoring, and tri-annual sanitary surveys. Recent updates to the Colorado Primary Drinking Water Regulations, going into effect in April 2016, reflect growing attention to the drinking water distribution system. Distribution system related updates include: adoption of the Revised Total Coliform Rule, which sets a treatment technique requiring systems to conduct assessments and identify corrective actions; more explicit cross connection program requirements; a required chlorine residual of at least 0.2 mg/L in the system in 95 percent of monthly samples (compared to the current requirement of having a detectable level of chlorine residual); and storage tank inspection requirements for at least quarterly inspections and comprehensive inspections at least every five years. The city does not anticipate compliance issues with the updated regulations. ANALYSIS – DISTRIBUTION SYSTEM TOOLS The city has been proactively implementing and upgrading distribution system tools to provide real time monitoring of the quality of the water going to customers’ taps and to optimize system water quality and operation. These tools help the city prepare for future regulations and better understand the extensive system, and are identified in studies above as critical to maintaining Information Item #4 Page: 2 hydraulic integrity and minimizing water residence times in pipes, storage facilities, and premise plumbing. Online Water Quality Monitoring The city’s 2006 Water Supply System Vulnerability Assessment recommended continuous water quality monitoring instrumentation stations in the distribution system as a means of providing real-time warning of potential water quality contamination. Data from these stations can serve as an early warning of water quality issues and can be used to improve system water quality through operational modifications. The city’s Drinking Water Quality Program, in cooperation with the Utilities Engineering group, has installed continuously-monitoring water quality panels at five sites throughout the distribution system which provide up-to-the-minute information about distribution system water quality (Attachment A). Three of the panels are located at finished water reservoirs, and two of these three can monitor water from three different depths in the reservoir to ensure water quality is consistent throughout. The remaining two panels are at pump stations and can monitor water from either the suction or discharge side of the stations. To ensure accurate data collection, city staff performs monthly calibration, maintenance, and troubleshooting for the online instrumentation. To help save costs, the panels have been installed in coordination with other facility site improvement projects. The panels monitor for turbidity, chlorine, pH, conductivity, and temperature, and output data to the water treatment and distribution supervisory control and data acquisition (SCADA) system. These parameters are standard for monitoring general water quality as they can detect bacterial growth, sudden chlorine demand, potential corrosion, or sediment in the system. These parameters are also consistent with other monitoring in the distribution system and at the water treatment facilities. Data from the water quality instrumentation trigger alarms and emails to staff if the values fall outside of standard operating ranges, which are more restrictive than regulatory limits. For example, if the chlorine residual in water leaving a finished water reservoir is below target levels, Water Treatment operators will be automatically notified and can change reservoir fluctuation levels, or Utilities Maintenance staff may go flush the area to freshen residual chlorine. Occasionally, turbidity spikes in the water going through a pump station have been attributed to main breaks in the system. BlueBox Early Notification System The city’s Vulnerability Assessment recommends adding more distribution system monitoring stations as an early notification system for accidental or intentional contamination. However, data from the existing sites has not always been dependable, despite a strong preventative maintenance program. Maintaining instruments at remote locations can be difficult due to power outages, heating/cooling system outages, drift in the readings, plumbing, and other issues. In addition, contaminants may be introduced to the system through a backflow incident, main break, or accidental or intentional contamination, and some known waterborne contaminants Information Item #4 Page: 3 have the potential to change water quality parameters so slightly that standard alarms may not trigger. To improve dependability, increase the ability to differentiate between real and false alarms, and detect unusual combinations of water quality parameters that may not be detected by individual parameter changes, the city implemented a BlueBox Event Detection system in 2012 (Attachment B). This system analyzes data from water quality stations and builds a baseline multi-dimensional database, or ‘fingerprint,’ for each station from historical data. Anytime a data set falls within the fingerprint, operation is normal. If the combination of data points falls outside the fingerprint because it has not been seen before, or if it has been previously user- categorized as abnormal, the software sends a notification or an alarm. The system can also remember common events such as a turbidity spike after a pump comes online and will not send alarms in these situations. Distribution System Hydraulic Model and Live Modeling City staff built and maintains a full pipe distribution system hydraulic model using Innovyze Infowater software that matches the city’s GIS water main layer. The model includes friction factors based on age and material, fire hydrants, seasonal diurnal use curves from actual SCADA data, demands from actual meter and billing data, pump and hydroelectric turbine curves, operational controls, elevations assigned from GIS contour layers, and seasonal operational scenarios. The city’s Infowater hydraulic model is well calibrated and an excellent representation of system hydraulics. The model is regularly used for planning to simulate demands from new development, facility outages or upgrades, water age, and fire flows. The model is also used to evaluate ongoing operations and system impacts, and model simulations can be steady state or extended period. A steady state simulation is essentially a snapshot of the system under a specific water demand condition, while an extended period simulation looks at system demand fluctuations and operational changes over a user-defined time period (Attachment C). The city is one of the first utilities in the U.S. to also implement real-time hydraulic modeling which connects the hydraulic model with SCADA data from the distribution system and provides boundary conditions for each simulation (Attachment D). The live model can run in forecast or forensic mode. In forecast mode, the model uses real-time distribution system data to set the initial model conditions and projects the coming hours of system performance using current production and demand data. The model can automatically run every hour, simulating current and near future conditions in the system based on standard operating controls, and notifying staff should any modeled data fall outside of target operating ranges. The hourly runs can be adjusted to evaluate water age and pressure results from different operating scenarios such as valve closures or targeted tank fluctuation (Attachment E). In forensic mode, the model recreates a past operating scenario from a start date selected by the user. There are no operating controls in a forensic model and the model runs exactly according to SCADA data. For example, if the Cherryvale pump was shut off by operators at hour 8, it will Information Item #4 Page: 4 be shut off at hour 8 of the scenario. Forensic mode is especially useful for performing a field calibration when the system is under stress (peak day or fire flow) (Attachment F). In both modes, model results are compared to verification points from the system, which include pressures, flow rates, and reservoir levels. As the real-time hydraulic model continues to move ahead, it will be invaluable for further studies such as analysis of water age under different operating scenarios and optimization of pumping schedules that will yield the lowest operating cost while satisfying system performance requirements. Storage Tank Monitoring The water distribution system has six storage tanks with a total of 38 million gallons of water storage. Tanks are fluctuated as part of standard day-to-day operations. To monitor conditions inside the storage tanks, staff installed temperature probes at varying depths in all six tanks. The data is pulled twice a year and analyzed to determine if stratification is occurring in any of the tanks. Temperature stratification is typically an indication of a lack of mixing, which can lead to pockets of old water with low or no chlorine residuals. The city has three pressure zones: zone 3 is the furthest west with its eastern boundary roughly along Broadway; zone 1 is the furthest east with its western boundary roughly along Foothills Parkway; and zone 2 encompasses the large area between zone 1 and 3. At Devil’s Thumb storage tank, located in zone 3, temperature data indicated temperature stratification was occurring primarily during summer months. To address stratification, a passive mixing system was installed. Staff continues to monitor the temperature and will be evaluating the improvements from the mixing system. Similar mixing systems were previously installed at the two other zone 3 tanks, Booton and Chautauqua, to address similar stratification issues, and data from both tanks has indicated good mixing (Attachment G). Temperature data from the Gunbarrel Tank, located in zone 1, has shown some stratification and continues to be monitored. Neither zone 2 tank, Maxwell or Kohler, has shown signs of temperature stratification. Partnership for Safe Water for the Distribution System The City of Boulder became a charter member in the Partnership for Safe Water Distribution System Optimization Program in 2011. The Partnership for Safe Water began in 1995 with its program to optimize water treatment plant performance and added the Distribution System Optimization Program in 2011. The goal of the Partnership is to implement prevention programs where legislation or regulation does not yet exist. The Partnership program provides tools to assess treatment plants and distribution systems and benchmark their performance in relation to other utilities in their region and across the nation. There are four phases to the Partnership: Phase I – commitment; Phase II – baseline data collection and annual reporting; Phase III – self assessment; and, Phase IV – optimized system (optional). The Phase III self assessment is a self-paced, significant effort that allows the utility to examine the capabilities of the existing system’s operation and administration and resultant Information Item #4 Page: 5 identification of those factors that limit performance. Once the utility has performed this self examination, it develops a plan for implementation of improvements. The Phase III completion report summarizes the self-assessment results and is reviewed by a team from the Partnership Program Effectiveness Assessment Committee (a group of trained utility professional peers) to make sure the process is productive, effective, and unbiased. The city’s Water Treatment staff achieved Water Treatment Phase III for both treatment facilities in 2011. In 2015, Drinking Water Program staff will start the Distribution System Phase III self assessment, a significant multi-group effort. The program analyzes the following distribution system metrics:  disinfectant residual  pressure management  main break frequency  cross connection control / backflow  disinfection by-product control  energy management  external corrosion  flushing  maintaining valves / hydrants / blowoffs  internal corrosion control  pipeline installation / replacement / rehabilitation  post precipitation control  security, emergency management  storage facility operation and management  water age and the hydraulic model  water loss control  water quality sampling and response  asset inventory  pipeline materials  pumping facilities  valves and hydrants  application of operational concepts  administrative factors  an action implementation plan NEXT STEPS Surveillance and Response System (SRS) Surveillance and Response Systems (SRS) are software systems that incorporate inputs from several components which may include online water quality monitoring and event detection systems, sampling, enhanced security (such as security cameras), customer complaints, public health information, and work order management systems. These data are used as an early warning system of contamination in the distribution system. SRSs are relatively new systems that have been developed in mostly large scale utilities. A recent Water Research Foundation study found that SRS drivers include security concerns, grant availability, customer demands for information, internal distribution system water quality and security initiatives, and specific events degrading water quality. SRS benefits to utilities include improved operations and reduced operations costs, improved levels of service, demonstration of due diligence to public and regulators, reduced repair/replacement costs, improved coordination across utility divisions, improved interagency cooperation, and improved documentation of procedures. Barriers to SRS implementation are significant cost, increased complexity, achieving buy-in, and public perception. Information Item #4 Page: 6 Under current conditions, if the distribution system experiences a potential water quality event, Drinking Water Program staff may check all of the above components individually. Streamlining information flow through an SRS system would significantly improve incident identification and response time. Identification and response time will improve when the city Utility Maintenance Management System software is upgraded in coming years. A full scale SRS implementation is not planned at this time, but an achievable and desirable goal is to incorporate components in steps in coming years. ATTACHMENTS: A – Iris Pump Station Online Water Quality Monitoring Panel B – BlueBox Event Detection System Screenshot C – Infowater Hydraulic Model – 30 Day Simulation – Water Age Example D – SCADA Data Linked By Live Hydraulic Model E – Running Operational Simulations to Prepare for Facility Outage - Example F – Verifying Model Calibration Using Stressed Field Condition G – Finished Water Tank Stratification Study Example Information Item #4 Page: 7 ATTACHMENT A IRIS PUMP STATION ONLINE WATER QUALITY MONITORING PANEL Attachment A: Iris Pump Station Online Water Quality Monitoring Panel ATTACHMENT B BLUEBOX EVENT DETECTION SYSTEM SCREENSHOT Attachment B: Bluebox Event Detection System Screenshot ATTACHMENT C INFOWATER HYDRAULIC MODEL – 30 DAY SIMULATION - WATER AGE EXAMPLE Attachment C: Infowater Hydraulic Model - 30 Day Stimulation ATTACHMENT D SCADA DATA LINKED BY LIVE HYDRAULIC MODEL Red circles indicate water system assets with data feeds Attachment D: SCADA Data Linked by Live Hydraulic Model ATTACHMENT E RUNNING OPERATIONAL SIMULATIONS TO PREPARE FOR FACILITY OUTAGE - EXAMPLE Attachment E: Operational Simulations for Facility Outage - Example ATTACHMENT F VERIFYING MODEL CALIBRATION USING STRESSED FIELD CONDITION Model results vs actual system data Attachment F: Verifying Model Calibration ATTACHMENT G FINISHED WATER TANK STRATIFICATION STUDY EXAMPLE Onset Hobo Water Temperature Data Logger Temperature Probe Data – indicating temperature differences between the top and bottom probes Tideflex valves installed Devil’s Thumb Tank in May 2014 Attachment G: Finished Water Tank Stratification Study Example