HomeMy WebLinkAbout5 - Comprehensive Flood and Stormwater master plan update, stormwater drainage and quality key issueCITY OF BOULD~R
WATER RESOURCE ADVISORY BOARD AGENDA ITEM
M~ETING DATE: September 15, 2003
SUBJECT: Staff presentahon and WRAB discussion on the Comprehensive Flood and
Stormwater (CF5) master plan update, stormwater dramage and quality key issues and the role
of the Inde endent Review Panel (II2P) and the Citizen Review Grou (CRG).
REQUESTING DEPARTMENT:
Ned Williams, Director of Public Works for Utihhes
Bob Harberg, Utilities Plannmg and Pro~ect Management Coordinatar
Douglas Sullivan, Utilities Pro~ect Manager
Donna Swtt, SCOrmwater Quahty Coordinator
Jeff Arthur, Develo ment Review Coardmator
BOARD ACTION REQUEST~D: None at this time. Staff is providing WRAB an update on
the Comprehensive Flood and Stormwater (CFS) master plan update, includmg stormwater
drainage and quality key issues and the role of the Independent Review Panel and the Citizen
Review Grou and will re uest the Board's comments and in ut.
FISCAL IMPACT: None at this time. Follow-up work will need to be priorirized and
funded as art of the on- om bud et rocess.
The Comprehensive Flood and Stormwater (CFS) Master Plan is the policy that drives efforts in
flood management, stormwater drainage and stoirnwater quality. The city's current master plan is
referred to as the Comprehensive Drainage Utility Master Plan (CDUMP) and was adopted m
1989. The name of the plan has been changed to reflect the sigruficant effort that also goes mto
Flood Management under the Utilities Division of Pubhc Warks. The intent of this update is to
review various policy alternatives and provrde recommendations for any existmg programs
adjustments
Staff hired URS Consultants to help with the development of the master plan update. They have
completed technical memos concernmg stormwater drainage and stormwater qualrty The
mformation contained in the technical memos was used to identify key issues as discussed in the
attached informahon. These issues were reviewed by the Independent Review Panel (IRP) and
the Citizen Review Gtoup (CRG) at meetmgs in AugusC.
The next step is to identify key issues related to various flood management work including flood
mappmg and regulations and a meetmg with the CRG is scheduled far September 18.
Staff will present this mformation to the WRAB and requests the Board's comments and mput.
Attachment A: Stormwater Dramage Key Issues
Attachment B: Stormwater Quality Key Issues
Attachment C: Informahon Concernmg Review Groups
Attachment A
STORMWATER DRAINAGE
KEY ISSUES
September 9, 2003
Undate the Storm Water Collection Svstem Plan
Background
In 1984 the Storm Water Collection System Master Plan by WRC Engineering Inc was
completed to provide the City of Boulder with a guide to Capital Improvement Pro~ect (CIP)
development. This master plan mcluded three phases of development.
• To review and develop hydrologic data and create a model to analyze the existmg
storm drainage system
• To evaluate the existmg system and identify problems withm the study area and
develop a matrix of alternatives to solve the problems
• To complete preliminary design of selected improvement alternatives
Detenrion was evaluated and it was considered only when undeveloped land was available, and
only when it could reduce the mihal storm flood peaks to the capacity of the existing system The
final list of selected pro~ects did not recommend any detention ponds.
Each of the projects was evaluated based on cost, providmg a higher level of flood protechon,
reduchon of street flow, and the ability to provide stormwater release points for irrigation
ditches. The "selected" projects were then prioritized and added to the CIP list The CIP list
includes all pro~ects selected for Boulder mcluding ma~or drainage improvement projects,
stormwater dramage pro~ects (storm sewers) and water quality pro~ects. The Storm Water
Collectron System Master Plan conhnues to serve as the City's primary guide to allocate
resources for stormwater drainage (storm sewers) purposes
The City has recently created a GIS layer of sub-basins and sub-catchments, contaming pertinent
information that may be used as a basis to update the hydrology and hydraulic modeling.
Information from Other Communities
None of the other commumues contacted have developed a separate storm dramage plan to
define drainage problems and solutions for frequent storm events. Most commumties have only
designed systems for less frequent (100-year) storm events, and developed solutions for more
frequent events on a concurrent basis except for the City and County of Denver which also has a
Stormwater Drainage Plan "Denver Storm Dramage Master Plan." Denver recommends updatmg
their plan every few yeais. They last updated their plan m 1989.They have recently selected
consultants to update several basins
Public Input to Date
This issue was reviewed and discussed as part of the CRG meehng on August 14, 2003. It was
suggested that the City not spend money on remodeling and restudying those areas we know
about; look at known pioblem areas and areas that are gomg to be developed in future
Regional detenhon may have some real benefits, however a city as built out as Boulder,
opportunrties may be limited. The exception might be detention that is integrated with Park
development or expansion of existing private detention. We should be lookmg for other
oppoitunrties to put everyone's money mto places where we can get the most benefits.
Recommendations
Update the City's Storm Water Collection System Master Plan addressing the followmg issues:
• Current and future land use and associated imperviousness
• Update hydrology/hydrauhc models
• Consider groundwater flows when evaluating existmg capacity
• Peak flows for the minor and ma~or storm events
• Focus on known problem ateas and future development
• Integrate water quality and other multi-ob~ective issues
• Reevaluate detention includmg the possibility of regional detention and existing
detenhon
• Locate (estimate) the water table throughout Yhe city
• Re-evaluate iemaining pro~ects for necessity and communrty ob~ectives
• Reprioritize recommended projects
Maintenance Manaeement
Background
Stormwater and Flood Management masntenance activities are currently tracked using the
Utilities Maintenance Management System (UMMS), a Microsoft Access database. The database
is designed to record mformation related to 1) employees, 2) equipment, 3) parts, 4)
observations, 5) mamtenance activity, 6) work orders, 7) infrastructure and 8) administrahon
UMM5 is currently being integrated with the City's GIS. The GIS captures the majority of all
publicly owned stormwater facilities including storm sewer, manholes, mlets and small diameter
culverts
The system does not currently mtegrate above grade facilrties associated with the major
drainageways. However, these facilities were recently mventoiied as part of the Diainageway
Information Management System (DIMS) and are now available as a GIS layei Maintenance
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responsibility for these facilities is shared with the Urban Draznage and Flood Contiol District
(UDFCD).
In addition, the Call I,og database is a stand alone system that has the ability to assign tasks to a
selected hsL of mdividuals and can accommodate multiple tasks assigned to mulriple persons for
any given problem. Individuals do not currently mclude project management personnel.
Information from Other Communities
Surveyed commuruties generally have an automated system that tracks incommg complamts.
These database systems aie often used for the prioritization of projects as well as the
determmarion of the timmg and development of the best course of action to ehmmate the
problems, track the follow-up, and mspechons Most databases are also connected to a map
(GIS) inventory system.
Public Input to Date
This issue was not discussed at the CRG meeting on August 14, 2003 since it was considered an
mYernal issue to the City's Public Works Department.
Recommendations
Integrate above grade facilities associated with the major drainageways (DIMS) mto UMMS.
Integrate ma~or mamtenance and all mfrastructure upgrades performed by the UDFCD into
UMMS. Include appropriate pro~ect management personnel in the Call Log database
On-Site Detention Reauirements
Background
The Crty has required on-site detenhon for development and redevelopment smce the early
1970s On-site detention storage is required for all developments other than mdividua] smgle-
family lots that are not part of a larger development.
Current detention requirements are based on non-degradation of stormwater quality and peakmg
flows. For example, redevelopment is only required to detain the mcrement of difference
between the exishng developed and new developed conditions.
Information from Other Communities
Most communities interviewed require that redevelopment detam any addrtional runoff volume
generated above the amount generated from the site before redevelopment (same as Boulder).
One community (Fart Collms) requires that redeveloped sites comply wrth current ciiteria if the
site is completely redeveloped. Cuirent critena is deYenhon of the 100-year event, release at the
existing 2-year rate with 40-hrs of detention hme for WQ.
Public Input to Date
This issue was reviewed and discussed as part of the CRG meeting on August 14, 2003. It was
suggested that incentive-based performance standards should be used instead of fixed regulatory
schemes, particularly for retrofitting where every situahon is different. There are concerns of the
tremendous potential for considerable cost to be borne by property owners. Prior to movmg from
a non-degtadahon based approach to an approach that contemplates improvmg starmwalei
quality and detammg addihonal peak flows there needs to be careful consideration of the
associated costs and benefits.
Recommendations
Review each development plan to look for opportunities to increase detenuon in addirion to the
minimum currently required. This could be based on the degree of redevelopment proposed. This
could be part of an incentive plan, where going above and beyond would decrease fees.
Prior to considering addihonal detenrion requirements for redevelopment, carefully assess the
associated costs and benefits Review this issue as part of the update to the Stormwater
Collection System Plan.
Insnection and Maintenance of Existing Detention Facilities
Background
The City has required on-site detenhon for development and redevelopment since the early
1970s. The design of these facilrties is reviewed by City staff at the time of application. The
facilities are mspected and as-built drawmgs are now required to be submitted. All such facilrties
are privately owner and mamtained.
The City is currently entering known detention facilities mto a GIS data base and plans to
perform a condit~on assessment of a random sampling of the facilities to determme if they are
still servmg their intended purpose.
Information from Other Communities
Most local municipahties do not have any requirements or programs for mspecting and
maintammg existing deYent~on facilihes with Yhe excepYion of Fart Collins which conducts
annual mspections and maintenance of 82 city owned detention facilities. Some of these are
regional facilities origmally constructed by the city as a capital improvement projects and other
facilitres are associated with iesidential subdivisions. They also have ovei 500 privately owned
detention facilrties, for which there is no mspection and mamtenance piogram at this rime.
The City Overland, Kansas has required annual inspections and cei1ifications of private detention
fac~lities smce the late 1980s. The inspection must be stamped by a professional engineer and
must certify thaC that outlet structure is funchomng and that the detenCion facility contmues to
provide its design storage.
Kmg County takes ownership of detention facilihes associated with residential subdivisions and
they inspecdmaintam these facilihes once every 2-3 yeais of ovei 1000 fac~lrties. They also
inspect new detention facilities associates with iesidential subdivision durmg the 2-year bond
period once each quarter. The frequency is greater because this is the hme period when erosion
causes the greatest problems with the detention facility. In 2003 the work program calls for a
total of 550 mspections and follow-up. In addihon they mspect approximately 800 private
(commercial/industrial/multi-family/government) facilities on a 2-3 yeaz rotatmg basis. If they
find a problem they send a letter notifymg the propeity owner of non-compliance and that
correction is needed. They provide an incentive discount on the uhhty bill if the facilrty is in
compliance, however they do not think lhis mcentive is large enough. As a result they will begin
taking enforcement action next yeaz.
Public Input to Date
This issue was reviewed and discussed as part of the CRG meetmg on August 14, 2003.
Although no consensus was reached, it was suggested that the City should mventory and
periodically inspect these facilities but not necessarily assume maintenance iesponsibility. The
City should consider requ~rmg the owners of existing water quality and detention ponds to be
made fmancially responsible for returning their facilrties to their origmal design conditions and
maintatmng them to keep them funchonmg m accordance wrth their origmal design.
Recommendations
Require property owners to submit an inspection report stamped by a registered professional
engineer to the city once every 5 years certifying the detention facility is funchoning as
origmally designed or a plan for improvements. Otherwise impose a fine if they are not
comphant.
Pros
Assure that detention facilities are serving their intended purpose
Cons
Cost to private property owners for inspection report
Cost to City for enforcement and review
Maintam the inventory of detenhon facilihes. Reassess the ophon of the crty assuming on-gomg
inspection and maintenance of detention facilities in 5 years. Revisit this when the Stormwatei
Collection System Master Plan is updated.
Priorrtize this work with other Stormwater and Flood Management Utilrty work progiams
Requirements for Groundwater Extraction and Release
Background
Groundwater and sump systems create nuisance drainage in the public rights-of-way and can
create hazards As such, the Crty of Boulder is refming requirements for gioundwater extracrion
and release prior to, durmg and after constiuction
The city currently requires an analysis of groundwater condihons contributmg to site runoff
mcluding water table mformation as part of a Stormwater Report and Plan. There is also a
groundwater discharge permitYmg system in place to supplement state regulations.
The areas we need help on are what we should allow and how that impacts our infrastructure
needs. Should we be prohibiting subsurface improvements in some areas and if so what are the
impacts? Do we need to update our drainage system master plan to account for groundwater
discharge and if so, how does this impact our prioritizahon? How are other cities dealing wrth
this issue? The water table information we get in soils reports isn't all that precise. How do we
be proactive rather than reactrve (as we are now) in dealmg with groundwater issues when we
may not have rehable data on discharga needs until a structure is up and runnmg?
Information from Other Communities
Most communities do not have a requirement to control groundwater discharge after
construction. Generally, commumties require a Soils Report as part of development along with a
Stormwater Polluhon Prevention Plan. However, except far the City of Fort Colhns, Colorado,
none of the communities interviewed require the identification of groundwater levels and/or a
development plan to control groundwater But, cities like Portland require a mitigarion plan if
high groundwater is suspected For disposal of groundwater they have different groundwater
discharge criteria for each area (mfiltration conditions) within their~urisdiction.
Public Input to Date
This issue was reviewed and discussed as part of the CRG meeting on August 14, 2003.
Comments mcluded supports for groundwater mitigation requirements. Sewers have dewatered
wells m North Boulder. It is especially important that city have good inspection of check dams.
Another commenter didn't suppart performance-based standards or regulations that would
require everyone to test the groundwater table. Although this may be appropriate for certain
zones of the city; there are other areas where it would not be of concern.
Ground water involvement looks like a real nightmare at this time. Why not focus on things we
can effectively do now? IY appears from all the checking wiCb other communities thaY no other
commumty has tackled this issue and there is a good reason for this.
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Recommendations
Identify problem areas and require moie precise water table mformation that considers seasonal
fluctuations. If the City believes or knows of a problem area, then a miugahon plan should be
required prior to the permittmg. If groundwater is not expected but is encountered durmg
construchon then a mRigaYion plan should be raquired prior to issuing the certificate of
occupancy. Evaluate the imphcarions of groundwater contammation and levels from
underground storage tank data and further explore existmg available soils informarion.
Pros
Better assures that groundwater pumpmg and discharge will not create problem
condiCions
Cons
Cost to private property owners for mitigation plan
Cost to City for review and enforcement
Consider groundwater discharge as part of the update to the Stormwater Collection System Plan.
Identify problem areas and issues includmg the affect of groundwater dewatering on local water
wells Develop mitigation options for specific problem areas based on estimates of additional
groundwater flow.
Attachment B
STORMWATER QUALITY
KEY ISSUES
September 9, 2003
(Integratecl Approach)
Background
Prior to urban development, precipitation can soak into the ground and infiltrate mto
groundwater- very httle ramfall is converted to runoff. Urbanization disrupts the natural
response of a watershed, decreasing the rate of infiltration and increasmg runoff. The
characteristics of a basm, m terms of the amount of developed lands and impervious surfaces
are key contributing factors m the quantrty (floodmg) and quality (stream health) of urban
streams such as Boulder Creek and its tributaries
Traditionally, alleviatmg floodmg problems have focused on efficient rouhng and removal of
stormwater with little consideration to environmental impact. Similarly, water quality
improvements have focused on specific sources of pollurion, such as erosion. While this
approach may be successful m addressing site-specific problems, it often fails to addtess the
more chronic problems that contribute to the long-term deterioration of water quality.
The overall goal of the Comprehensive Flood and Stormwater (CFS) Master Plan is to integrate
three key objectives of flood protection, drainage management and water quality. A watershed
management approach offers an opportumty to balance quanhty and quality issues. This
approach allows for the development of soluhons with multi-faceled benefits to the stream
corridor and the dramage basm.
It is often difficult to meet multiple, often compehng, ob~ecrives m a plannmg process or m
implementmg programs. However, one example of how the city has successfully met this
challenge is the Greenways Master Plan. Completed m 2000, the Greenways Master plan
provides a set of specific pro~ects which are prioritized by objective. If conflicts between
ob~ectrves exist on a partrcular pro~ect, these conflicts are worked out durmg the project design
level. This two phase, plamm~g and implementation approach helps to maintain multiple
ob~ective benefits. The watershed or multiple ob~ective approach can also be used m the CFS
Mastei Plan to develop criteria and set priorities in flood protection, dramage management and
water quality programs, capital impiovement pro~ects, and regulations.
Information from Other Communities
The City of Fort Collins uses a watershed approach to stormwater management, includmg sub-
basm based requirements and a system for assessmg and balancing compering ob~ecrives. In
Portland, Oregon, watershed plans are intended Yo integrate water quahty issues wiYh the
planning of public facilities, land use, and redevelopment efforts. It is noted that in reality they
have trouble coordmatmg these efforts simply because of size and compiexrty of issues. The City
of Ausrin, Texas uses a"needs-based" approach that ranks projects based on mission priorities
mcludmg flood mitigahon, erosion contiol and water quality.
Public Input to Date
This issue was reviewed and discussed as part of the Community Resource Group (CRG)
meeting on August 14, 2003. There was some support for using a watershed prioritizahon
approach. However, the concern was raised that a watershed approach would slow down the
plamm~g process and shift resources away from flood mitigation plans. One participant
suggested that more pro~ects should be completed and fewer plans be made. Another participant
felt that money would be much more effectively spent on inspection and maintenance of existing
BMPs rather than on studies.
Recommendations
Develop and implement a wateished prioritization system, based on GIS information and
analysis that incorporates water quality, drainage, flood management, development, and land-use
planning data In addrtion, this priaridzation system should incorporate and support the
Gieenways Master Plan and wetlands protecrion.
Use the impendmg updates to the Stormwater Collecuon System Plan, the Design and
ConstrucUon Standards and Boulder Valley Comprehensive Plan (BVCP) Land Use Map as
opportunihes to integrate watershed based water quality information and issues.
Expand Greenways Master Plan, to mclude all major tributaries of Boulder Creek (curiently the
program is limited to Boulder Creek and six major tributaries).
Pros
• The most effechve way to protecdpreserve water qualrty and riparian habitat is to
mtegrate water quality thiough interconnected dratnage and flood management
systems m urbanized basms.
• A watershed approach to management of stormwater quahty issues is the most
complete system to evaluate water qualrty issues
• GIS is an effective tool, which has been effectively coordinated for analyzmg city-
wide geographical data sets.
Cons
• May hinder waCer qualrty activities by hnkmg tbem to the polit~cal process.
• Cooperation with other departments requires more time out of alieady busy
schedules, additional staff resources may be needed.
• Open Space objectives foi Boulder Creek tributaries may not be compaCible with
management ob~ectives far tributaries that dram urbanized areas.
• Expansion of city GIS services may require additional city resources for staffing and
training.
Best Manasement Practices for Redevelopment and Imulementine BMPs in
Existins Development Sites
(Treating Runoff)
Background
The city's Phase II Stormwater permit requires the city to implement development
regulations which address impact of runoff from new and redevelopment srtes. The crty is
currently participatmg in the Watershed Approach to Stream Health (WASH) pro~ect. Other
participants mclude: Longmont, Erie, Superior, Louisville, and Boulder County To meet
permit requirements, the WASH pro~ect is drafting development standards based on the
Urban Dramage and Flood Control District (UDFCD) Urban Storm Draina~e Criteria
Manual Volume 3 Best Management Practices (UDFCD Vo13).
In addition, the city's existmg Design and Construction Standards reference UDFCD Vol. 3
This is a well-accepted document based on years of experience and field testing in the Denver
area, as well as research conducted throughout the country. However, most of the BMPs
mcluded in UDFCD Vol 3 address new development rather than redevelopment ar adding BMPs
to existing development. Boulder is predommantly built out, and guidelines focused on new
development have limited apphcability m denser, redevelopmg areas. Therefore, to address
water quality concerns, more mnovatrve runoff treatment solutions need to be considered To
encourage these solutions, historically, the crty has been receptive to a variety of mnovahve
BMPs. However, many developers have been reluctant to implement BMPs other than those
represenhng tradrtional approaches.
Information from Other Communities
In Portland, Oregon mfiltration trenches are pnmarily used m single family residential area, the
stormwater planters and mfiltration basins are very popular for commercial/multi family
srtuations, and then ponds are shll popular m mdustrial and subdivision type situations. These
types of approaches could be useful for mcorporation into redeveloping sites.
In Austtn, Texas the mmimum standard of pollutant removal for permanent BMPs is based on
sand filtration. Permanent BMPs are not required unless ~mpeivious cover exceeds 20% For
selected ateas of high background water quality, new developments must meet a non-degradation
standard.
Public Input to Date
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This issue was reviewed and discussed as part of the CRG meetmg on August 14, 2003. During
this meeting, there was a general preference expressed for performance-based requirements that
are flexible and provide financial mcentives. It was suggested that the city should considei a
pomt system similar to the LEED program One participant raised the concern that considerable
cost for BMPs would be borne by property owners and developers and therefore, the cost of
additional requu•ements and associated water quahty benefits should be carefully assessed. The
comment was made that the responsibilrty is and should be on the property owner.
Recommendations
Research BMPs oriented to redevelopment and BMPs for existmg development (for example,
eco-roofs, cisterns, underground treatment) and mcorporate appropriate methods, such as Better
Site Design, into crty standards. The use of underground storage and treatment BMPs should be
pursued as pilot programs and opportunities for grant money should be explored.
Develop a BMP implementation plan for urbamzed watersheds and explore the use of subsidies
and paitnerships with development companies, landscape professionals, and property owners
Better utilize existing stormwater fee incentives to encourage better design and construction
practices. Look at ways to encourage innovarion such as detenhon areas trade-offs for use of
alternative BMPs, such as porous pavement.
Promote BMPs m smgle family residential landscapes by changing Gieen Pomts program
(B.R.C. 9-3.3-24). Currently, pomts may be eained accordmg to only one criteria stated as
follows• '3 pomts - Use of engmeered swales to filter storm water runoff (these pomts are
awarded only if swale is not required by site plan conditions).' Addrtional criteria and points
should be defined.
For commercial development, implement a water quality pomt system, similar to Green Points,
which would require the standard water quality capture volume and, require additional on-site
BMPs or mvestment in regional BMP.
Contmue to require UDFCD Vol 3 design guidehnes and implement ordmances developed by
the WASH pro~ect far permit comphance.
Use the impendmg updates to the Stormwater Collection System Plan, the Design and
Construction Standards and BVCP Land Use Map as opportuniries to mtegiate stormwater
qualrty BMPs and development Standazds.
Pros
• BMPs oriented to retrofit of existmg development should provide greater benefits m
highly urbamzed aieas of Boulder where water quality concerns are greatest
• Demonstration projects based on grants, partnerships, mcentrves and subsidies can be
used to evaluate design and implementation options.
Cons
• BMPs oriented to redevelopment and retrofitting existmg development with BMPs
may be costly and may compete with other redevelopment goals
• Programs based on partneiships, mcentives and subsidies may not achieve significant
reductions m pollutants and coirespondmg stormwater quality benefits.
(Preventing
Background
Currently, the City has programs that help mimmize imperviousness and directly connected
impervious areas. These include buying land through the Open Space and Mountain Parks
Department. The City also encourages new development to mmimize imperviousness and
directly connected impervious areas accordmg to gmdelmes of the UDFCD. These include grass
swales, buffers, and porous pavement design guidelmes.
Boulder is predommantly built out and has liuuted opportumhes to impact waCer quality with the
current requirements. Redevelopment that Boulder is experiences offers the opporturtity to
mtegrate pervious aieas where stormwater can infiltrate and be used m landscape areas.
Information from Other Communities
Portland, Oregon is considermg a discount program that would reduce the stormwater utrlity fee
by 1/3 for managing stormwater on your site. They also have a small grant ($5,000) program for
commumty groups to retrofit existmg development andlor restore natural areas.
A group of stormwater managers m the San Francisco azea (Bay Area Stormwatei Management
Agencies Association) has produced a booklet entitled Stari at the Source, which has Best
Management Practices (BMP) that are common to the hterature (e.g., swales) as well as less
common, more mnovahve ideas. Included m this latter category are yard "cisterns" with
permanently open outlets, which release water slowly. These should not be actual cisterns that
capture the water and thus are problematic m terms of water rights. The water that is slowly
released can be dramed to a grass area, vegetable garden, xeriscape garden, or other vegetarion.
To prevent drainage problems, a commitment to maintenance of this BMP is important.
Austin, Texas development regulations have relatively strmgent hmits on impervious cover for
the more sensitive watersheds (as low as 15% to 20%). There are no impervious cover lirtuts m
the urban watersheds, while suburban watersheds have hmits as high as 80% for commercial
sites
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Public Input to Date
This issue was reviewed and discussed as part of the CRG meeting on August 14, 2003 There
was a general preference expressed for performance-based requirements that are flexible and
provide financial mcentives. The goal to mmimize imperviousness and diiectly connected
impervious areas might conflict wrth another departmenYs requirement/objectives such as
Planning's "new uibanism" - not wanhng garages in front of residences, which would necessitate
buildmg longer driveways (i.e., impervious areas) than might otherwise be needed Supporiing
more density and mmimizing imperviousness may be conflicting objectives However, MDCIA
and "new urbamsm" do not have to be mutually exclusive For example, cluster development
can reduce density on a larger scale by reducing driveway and road area.
The side affects of using pervious materials - like pervious concrete should be considered.
Concern would be weed and grasses grow m these and this rtught have the unmtended
consequence of people usmg herbicides which may affect stormwater and groundwater quality?
Recommendations
Develop a runoff reduchon plan for urbamzed watersheds based on GIS mformation and analysis
to assess runoff reduction ob~ectives for each sub-basm. Runoff ob~ective should include post
development peak discharge rate limited to the pre-development discharge rate for smgle design
two year storm event.
More effectively use existmg stormwater mvestment fee incentives to reduce runoff. Explore the
use of additional subsidies and partnerships with development compames, landscape
professionals, and property owners.
Use existmg city-owned land for water quality protechon and enhancement to the extent
practicable. In addihon, expand ffood hazard acquisition program to mclude water quahty
improvement areas.
SigmficanC decreases in impervious area can be achieved at the individualloY level, that is,
changes m landscapmg by mdividual property owners To defei costs and promote support, it
may be effective to rely on public education and creation of mcenhves through garden shops and
nurseries.
Implement construction and development standards which include runoff and impervious area
reduction strategies. These strategies may include Better Site Design, landscape and parking
standards, Forest Green (using city trees to reduce runoft~.
Contmue to use UDFCD design guidelmes which address impervious area reduction and
disconnection strategies.
Use the impending updates to the Stormwater Collection Systein Plan, the Design and
Constiuction Standards and BVCP Land Use Map as opporlumhes to mteg•ate pervious area mto
city pro~ects and standards.
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Pros
• Mmimizmg imperviousness and directly connected impervious areas are mtegral
parts of any plan to ~mprove stormwater quality through source controls.
• Demonstration projects based on partnerships, incentives and subsidies can be used to
evaluate design and implementation ophons.
Cons
• Minimizmg imperviousness may conflict with other City land use goals such as "new
urbanism"
• Programs based on partnerships, incentives and subsidies may not achieve significant
reductions m impervious areas and corresponding stormwater quality benefits.
Attachment C
Information Concerning Review Groups
Indeqendent Review Panel
The IlZP was created m December of 1999 to assist Urilihes staff in the master plannmg and
flood mapping process for Fourmile Canyon Creek Durmg its review and mvestigation of
floodplam management and recommended infrastructure development for the Fourmile Canyon
Cieek flood basin, IRP members determined that the ciry would need to address policy
requirements contamed in the master plan update m order to make systemic adjustments to
traditional flood management practices In testimony before the Boulder City Council durmg the
Flood Management Study session in Febivary of 2001, IRP member Gilbeit White indicated that
the IRP had a profound interest in the master plan update as a vehicle for insurmg that future
development and flood protection practices prohibited addrtional designed "problems" m the
city's creeks and floodways. City Council members asked Dr. White if he and his colleagues
would assist with the master plan update. The IRP has contmued its work on behalf of flood and
dramage issues since then and is committed to pazticipatmg m the master plan update.
The IRP mcludes professor emeritus and flood-protection expert Dr Gilbert White, Co-directoi
of the CU Natural Hazards Center Mary Fran Myers, hydrologic engmeer and former city
council member Ken Wright, Colorado Water Conservation Board representative Brian Hyde,
and jommg with the original members for the master plan update, Urban Dramage and Flood
Control DistricC Directar Scott Tucker.
Citizen Review Groun (CRG)
Group Goal:
The purpose of the Citizen Review Group is to have a group of citizens who are affected by
and/or utihze the policies contamed in the city's guidance for stormwater dramage and flood
management, review mformation provided by the consultant and provide feedback. It is
anticipated the CRG will meet a total of four times during the engmeering and technical
mvestigation process.
The consultant will research and present suggestions and recommendations for use m the master
plan update. Input from the review group will be assembled as "reactions and recommendations.'
The group's feedback will be used for purposes of advisement and may or may not be used in the
updated master plan. All of the review group feedback will be forwarded with the draft plan to
the city's boards and commissions for their use m their own review of the draft plan.
CRG Reviewer's Role:
The review participants are asked to review the consultant's recommendations and give input. In
their review, participants are asked to evaluate the suggestions and recommendations against the
followmg queshons.
. How does this suggestion/recommendation affect my area of interest?
• How does this suggestion/iecommendation affect broader city-goals for which I am
concerned?
. What are the benefits and costs of adoptmg this suggestion/recommendation?
CRG Reviewer's Responsibilities:
Reviewers should, to the best of their ability:
• Participate m the three ieview group presentation meerings m August, September, and
October.
. Review materials provided for the three review meetmgs in advance of the meetmg.
. Ask clartfying questions on e-mail or at the review group meettng
. Provide candid and thoughtful comments and input to the project staff.
. Frame input to suggest "posrtive futures" for the city's utihhes program
. Focus on problems; not on people. Listen and treat all project participants with respect.
. Help project staff understand how suggestions and recommendarions help the master plan
serve Boulder's commuruty goals.
. Help pio~ect staff gather mput and mform other commumty-interest groups of the update
process
The Citizen Reviewers:
The individuals who are assisting with the review mclude•
Jerry Lee
Local developerBusiness mterest
Bill Mitzelfeld
Development Engineering Consultant
Alison Richards
TAB emeritus
Kathie Joyner
Greenways interest
Terry Rodrigue
BURA/Civil Engmeer
Peter Gowen
WRAB/Plan Board emeritus
water law consultant
So Boulder Creek resident
2
Stuart Grogan
Boulder Housing Partners
Affordable Housmg Developer.
Elizabeth Black
Affected neighbor
Jim & Kathy Snow
County residents
Ditch company reps
Bob McFarland
Citizen formerly commented
on CDUMPBoulder Creek Issues
Ken Hotard
Boulder Area Realtar Associatron
Realtor/busmess mterest.
Phil Simpson
Facihties Management at CU
Dave Webster
Boulder County Transportahon
Sara Michl
Jeannette Hillery
PLANBoulder/LOW V
Joe Howard
Director of Facilihes Management
Boulder Community Hospital
Large Area Business/ Developmg Business
Alan O'Hashi
Planrung Board
G~l Barth
WRAB member & Hydrologist
Charlie Manlove
Parks and Rec Board
Don Mock
Gov't Labs &Meteorologist