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HomeMy WebLinkAboutItem 4.12 - 2700 Consideration of the Green Stormwater Infra Page 1 of 3 STAFF REPORT CITY COUNCIL DATE: June 18, 2019 TO: Honorable Mayor and City Councilmembers FROM: Christopher L. Foss, City Manager SUBJECT: Green Stormwater Infrastructure Plan Prepared by: Shannan Young, Environmental Coordinator EXECUTIVE SUMMARY: The City Council will consider approving a Green Stormwater Infrastructure Plan that is required to meet mandates in the Municipal Regional Stormwater National Pollutant Discharge Elimination System Permit issued on November 19, 2015, by the San Francisco Bay Regional Water Quality Control Board. The Green Stormwater Infrastructure Plan is required to mitigate for the effects of urbanization, in general, on receiving water quality, and to demonstrate with reasonable assurance that pollutant load reductions required in the San Francisco Bay Total Maximum Daily Loads for polychlorinated biphenyls and mercury will be achieved. STAFF RECOMMENDATION: Adopt the Resolution Approving the City of Dublin Green Stormwater Infrastructure Plan. FINANCIAL IMPACT: The GSI Plan is an unfunded State mandate. The fiscal impact of adopting the Green Stormwater Infrastructure (GSI) Plan is not fully known at this time. Most project locations identified in this Plan have been desktop vetted as potentially fea sible for GSI implementation, but field verifications and project concept plans have not been developed. Staff completed a potential project cost analysis as part of the GSI Plan development and have estimated that GSI project design and construction co sts per acre treated vary from a median of $31,300 to $283,000. On-going operations and maintenance costs are estimated at one (1) percent to four (4) percent of construction costs, depending on project type. Currently, all funds for GSI Plan development and implementation have come from the Municipal Regional Stormwater National Pollutant Discharge Elimination System Permit General Fund Assigned Reserve. As part of the GSI Plan development, Staff conducted Page 2 of 3 an evaluation of funding and financing options including grants, alternate compliance, and public private partnerships. Staff will continue to explore a variety of these funding options. Approval of the Plan by the City Council will not immediately obligate the City to incur costs on the GSI projects. Implementation of GSI projects will be approved by the City Council like any other Capital Improvement Program (CIP) project. DESCRIPTION: The Municipal Regional Stormwater National Pollutant Discharge Elimination System Permit (MRP), of which the City of Dublin is a co-permittee, was issued on November 19, 2015. The MRP includes a requirement for each permittee to prepare a Green Infrastructure Plan (referred to hereinafter as the Green Stormwater Infrastructure Plan) that demonstrates it can meet targets for the amount of impervious surfaces to be retrofitted with green stormwater infrastructure (GSI) by 2020, 2030, and 2040, in accordance with mercury and polychlorinated biphenyls (PCBs) load reduction requirements in Provisions C.11 and C.12 of the MRP. In addition to the requirement to reduce mercury and PCB pollutant loading, the MRP also requires construction of GSI facilities to reduce, over the long term, the adverse water quality impacts of urbanization and urban stormwater runoff on receiving waters to the maximum extent practicable. As a milestone in the development of the GSI Plan, all permittees were required to approve a GSI Framework for the development of the GSI Plan by June 30, 2017. The purpose of the GSI Framework was to describe sp ecific tasks and time frames for development of the GSI Plan required in MRP Provision C.3.j. The City Council adopted Resolution 77-17 on June 20, 2017 approving a Framework for MRP Green Infrastructure Plan Development (Attachment 1). Green stormwater infrastructure is a term that refers to engineered structures or features that are designed to detain stormwater runoff and remove water quality pollutants. In addition to detaining and cleaning stormwater runoff, GSI facilities may be used to alleviate the urban heat island effect, provide improved bicycle and pedestrian safety, reduce localized flooding, help improve local air quality, and provide carbon sequestration opportunities, among other benefits. The City of Dublin Green Stormwater Infrastructure Plan (Attachment 3) accomplishes the following in accordance with the MRP: Includes a mapping and prioritization mechanism to identify and prioritize both private and public GSI project opportunities; Identifies locations and timeframes for implementing GSI, including numeric targets for retrofitting impervious areas to achieve mandated pollutant load reductions; Utilizes a regionally consistent process for tracking and mapping completed projects to ensure progress towards meeting the pollutant load reduction targets; Includes and references design and construction standards and typical details for GSI facilities to enable the successful completion of projects; Integrates with other planning efforts, including updating relevant Dublin plans, policies, codes, and ordinances to incorporate GSI for stormwater management and support the implementation of project opportunities; and Page 3 of 3 Evaluates long-term funding options, including for design, construction, and on - going operations and maintenance. By adopting the Resolution Approving the City of Dublin Green Stormwater Infrastructure Plan (Attachment 2), the City is demonstrating its long-term commitment to implement GSI to mitigate for the effects of urbanization on receiving water quality and to meet regulatory requirements. The GSI Plan serves as an implementation guide and reporting tool to provide reasonable assurance that pollutant reduction mandates in the MRP will be met. Monitoring GSI Plan implementation and an adaptive management process will be necessary to ensure that goals are achieved as we move forward with the GSI Plan. It is likely that the GSI Plan and the maps themselves will require modification in the future as Staff learns more about how to effectively incorporate and maintain GSI in the City of Dublin. The GSI Plan serves as a starting point to show how over the long term and as funding allows, the City of Dublin will transition its storm drainage system from traditional gray, or piped, infrastructure to an integrated approach that includes multi-benefit green stormwater infrastructure systems. STRATEGIC PLAN INITIATIVE: N/A NOTICING REQUIREMENTS/PUBLIC OUTREACH: None. ATTACHMENTS: 1. Resolution 77-17 2. Resolution Approving the City of Dublin Green Stormwater Infrastructure Plan 3. Exhibit A to the Resolution - City of Dublin Green Stormwater Infrastructure Plan RESOLUTION NO. 77 — 17 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DUBLIN APPROVING A FRAMEWORK FOR MUNICIPAL REGIONAL STORMWATER NPDES PERMIT GREEN INFRASTRUCTURE PLAN DEVELOPMENT WHEREAS, the San Francisco Bay Regional Water Quality Control Board adopted the Second Municipal Regional 5tormwater NPDES Permit (MRP 2.0) on November 19, 2015 as Order No. R2- 2015-0049; and WHEREAS, the City of Dublin is a permittee under MRP 2.0; and WHEREAS, Provision C.3J of MRP 2.0 requires permittees to adopt by June 30, 2017 a framework that describes specific tasks and timeframes for development of a Green Infrastructure Plan; and WHEREAS, a Green Infrastructure Plan describing how MRP 2.0 permittees intend to include low impact development drainage design into appropriate projects on public and private lands to meet Total Maximum Daily Load (TMDL) wasteload allocations for mercury and polychlorinated biphenyls and to reduce to the Maximum Extent Feasible adverse water quality impacts due to urbanization must be adopted by the City of Dublin City Council by June 30, 2019; and WHEREAS, the goal of low impact development drainage design is to reduce runoff: minimize land disturbance; minimize directly connected pavement and other impervious cover to the storm drain system; and remove pollutants from urban runoff using methods that employ natural processes of storage, detention, infiltration, evapotranspiration, and filtering of runoff through soil media as described in Provision C.3.c of MRP 2.0; and WHEREAS, the City of Dublin has demonstrated its commitment to an environmentally sustainable future through its policy goals and actions, including maintaining natural hydrologic systems. and intends to incorporate green infrastructure into projects when doing so will benefit the environment and when a funding source for construction of green infrastructure has been identified; and WHEREAS, in order to be in compliance with MRP 2.0, a Framework for Green Infrastructure Plan development has been prepared for the City of Dublin. NOW, THEREFORE, BE IT RESOLVED that the City Council of the City of Dublin hereby adopts the Framework for Green Infrastructure Plan Development, attached hereto as Exhibit A. to prepare said Green Infrastructure Plan. PASSED, APPROVED AND ADOPTED this 20`h day of June 2017, by the following vote: AYES: Councilmembers Biddle, Gupta, Hernandez and Mayor Haubert NOES: ABSENT: Councilmember Goel Reso No. 77.17. Adopted W012017. Item No. 4.7 Page 1 of 2 ABSTAIN: Mayor ATTEST: Dee .• cr4 Clerk Rasa No. 77-17, Adopted 612012017, Item No. 4.7 Page 2 of 2 s�s ❑UBLIN waiar City of Dublin Framework for Green Infrastructure Plan Development This Framework for Green Infrastructure Plan Development is organized as follows. Section 1: Purpose Section 2: Municipal Stormwater Permit Deadlines Section 3: Specific Tasks for Green Infrastructure Plan Development Section 4: Timeframe Far Green Infrastructure Plan Development Section 5: Staffing Assignments Section 6: Budget Section 7: Summary I. Purpose The purpose of the Green Infrastructure Framework is to describe specific tasks and timeframes for development of the Green infrastructure Plan required in Provision C.3.j of the re -issued Municipal Regional Stormwater Permit (Regional Water Duality Control Board Order No. 112- 2015.0049, adopted an November 19, 2015), which states in part: . The [Green Infrastructure] Plan is intended to serve as an implementation guide and reporting tool during this and subsequent Permit terms to provide reasonable assurance that urban runoff TMDL wasteload allocations (e.g., for the San Francisco Bay mercury and PCBs TMDLs) will be met, and to set goals for reducing, over the long term, the adverse water quality impacts of urbanization and urban runoff on receiving waters. The Plan is intended to describe how Permittees will shift their impervious surfaces and storm drain infrastructure from gray, or traditional, storm drain infrastructure where runoff flows directly into the storm drain and then to the receivIngwater, to green.... "Green infrastructure" refers to a sustainable system that: slows runoff by dispersing it to vegetated areas; promotes infiltration and evapotranspiration; provides for stormwater collection and use; and incorporates bioretention and other stormwater treatment methods to clean stormwater runoff and to help mitigate for increased stormwater flows that result from adding impervious surfaces to watersheds. In addition to cleaning stormwater runoff, green infrastructure may be used to alleviate flooding, can assist in reducing the urban heat island effect, and can be incorporated into the streetscape in the form of bioretention areas next to streets to enhance the bicycle -pedestrian environment. The most common types of green infrastructure built in Dublin to date include bioretention areas and vegetated swales. Permittees under the re -issued Municipal Regional Stormwater Permit (MRP 2.0) are required to incorporate green infrastructure into storm drain design on public and private lands to meet urban runoff total maximum daily load (TMDL) wasteload allocations for mercury and polychlorinated biphenyls (PCBs). Mercury is a natural, ubiquitous pollutant that continues to June 2017 Framework for Green Infrastruclure Plan Development be emitted into the environment through burning of fossil fuels, waste incineration and use in gold extraction. Mercury is highly volatile and is released to the atmosphere as B gas which is subsequently deposited on impervious surfaces via air deposition. On the other hand, PCBs are a class of manmade organic pollutants that were manufactured until they were banned in the United States in 1979. Due to their non -flammability, chemical stability, high boiling point and electrical insulating properties, PCBs were used in hundreds of industrial and commercial applications. Although no longer commercially produced in the United States, PCBs may be present in products and materials produced before the 1979 PCB ban. The San Francisco Bay Regional Water Quality Control Board (Water Boardf has indicated that the most likely pathways for PCB contamination of stormwater include building demolition at old urban, commercial or industrial sites (i.e. pre-1979) when appropriate best management practices are not used, and sediment movement at contaminated sites. The urban runoff wasteload allocation included in the TMDLs for both PCBs and mercury is a region -wide allocation; however, if the PCB and mercury pollutant load reductions are not achieved on a region -wide basis, the default allocation is based on the population of the permittee, not on the actual pollutant load located within each jurisdiction. Population based TMDL determination poses concerns for the City of Dublin. While Dublin will meet the 2020 wasteload reduction requirements for both mercury and PCBS, Dublin will not be ahle to meet the 2030 or 2040 wasteload reduction requirements mandated in MRP 2.0 and the TMDL even if green infrastructure were incorporated throughout the city. The reason Dublin will not meet the wasteload reduction requirement is because there are few known locations of PCB contamination within the city, and potentially the City may not be contributing to the current loadings under the population based formula. This also poses a concern for permit non-compliance for Dublin in future re -issuances of the MRP if the population based formula is not addressed and/or if permittees with known PCB contaminated sites are not able to install adequate green infrastructure projects such that region -wide, the stormwater wasteload allocations are met. In contrast, Dublin should be able to meet the 2030 and 2040 wasteload reduction requirement for mercury through the installation of green infrastructure on planned private development projects and public projects anticipated to be constructed during this timeframe. In addition to the TMDLs drivers, construction of green infrastructure projects is also required to reduce, over the long term, the adverse water quality impacts of urbanization and urban runoff on receiving waters. The Water Board included green infrastructure mandates in Provision C.3.j. of MRP 2.0 in lieu of expanding the definition of a C.3 Regulated project to include all projects that create/replace 5,000 square feet or more of impervious surface area (the current threshold is 10,000 square feet of impervious surface area) and to road projects that only replace existing impervious surface area. Urbanization increases both pollutant load and the volume of flow to local creeks and waterbodies as natural areas are converted to impervious surfaces. Green infrastructure helps to mitigate the environmental impacts of urbanization. The purpose of the Green Infrastructure Plan required under Provision C.21J.L(1) of MRP 2.0 is to guide the identification, implementation, tracking, and reporting of green infrastructure June 2017 Framework for Green Infrasi'mlclum Plan Development projects within the City of Dublin. The adoption of the Green tnfrastructure Framework is an acknowledgement by the City that it anticipates meeting the intent of MRP 2.0, specifically to reduce pollutant load of Mercury and PCBs to local creeks and San Francisco Bay insofar as pollutants exist within Dublin, to the extent that it can with the funding available. Funding is discussed in more detail in Section b, Budget. 2. Municipal Stormwater Permit Deadlines provision C.3.j.i.(I) of MRP 2.0 requires all perm ittees, including the City of Dublin, to approve a framework to develop a Green Infrastructure Plan by June 30, 2017. The complete Green Infrastructure Plan must be submitted to the Regional Water Quality Control Board by September 30, 2019. 3. Specific Tasks for Plan Development Preparation of the Green Infrastructure Plan will require the following specific tasks Identify Green Infrastructure Projects Potential future green infrastructure projects will be identified for inclusion in the Green Infrastructure Plan. This includes documentation of existing proposed plans for private and public development projects that would be subject to MRP 2.0 Provision C.3.1b. requirements to include stormwater treatment facilities. Projects subject to MRP 2.0 Provision C.3.b. requirements generally include: lj new public or private projects that create/replace 10,000 square feet or more of Impervious surface area, 2) new road projects that create 10,000 square feet or more of impervious surface, 3) existing road widening projects which include a new travel lane and create/replace 10,13D0 square feet or more of impervious surface area, and 4) special land use projects (restaurants, automotive service facilities, gas stations, and parking lots) that create/replace 5,000 square feet or more of impervious surface area. The Green infrastructure Plan will also document the continuing implementation and results of the City of Dublin's process, initiated in Fiscal Year 2015-16, to review planned capital improvement projects that are not subject to Provision C.3.b. stormwater treatment requirements, to identify the potential for incorporating green infrastructure pending identification of funding. Additionally, a tool developed by the Alameda Countywide Clean Water Program (Clean Water Program) will be used to identify, map, and prioritize potential green infrastructure projects that may be included in the Green Infrastructure Plan. Develop Tracking Procedures Tools and guidance provided by the Clean Water Program will be used to develop procedures for estimating the pollutant load reduction benefits of green infrastructure projects, and for tracking and reporting an completed projects. The procedures will be described in the Green Infrastructure Plan. Incorporate Guidelines and Typical Designs The Green Infrastructure Plan will incorporate guidelines for streetscape and green infrastructure project design and construction, and green infrastructure typical design drawings June 2017 FrBmawork for Green lnrrastWum Plan Dave ppment and specifications. These will be based on example guidelines, typical design drawings, and specifications provided by the Clean Water Program or other local agencies. The City of Dublin is currently evaluating local design details and is creating typical design details, standard specifications, and procedures as needed. Update Planning Documents As required, planning documents, including those listed below, will be reviewed and relevant sections of these documents will be modified, as needed, for implementing green infrastructure in public and private development projects to support the implementation of the Green Infrastructure Plan. If the planning documents are not scheduled to be updated prior to Green Infrastructure Plan development, a schedule for review will be provided in the Green infrastructure Plan. The review will include the following planning documents: • General Plan, specific plans, and area plans • Streetscape Master Plan Bicycle and Pedestrian Master Plan • Commercial Corridor Design Guidelines Scarlett Court Design Guidelines Pavement rehabilitation work plan Parks and Recreation Master Plan Evaluate Funding Sources An evaluation of funding sources for both construction and operations and maintenance of potential future public green infrastructure projects will be included in the Green Infrastructure Plan. Guidance provided by the Clean Water Program may be used to develop an in -lieu fee for private development projects that are constrained from fully meeting Provision C.3.b. stormwater treatment measures onsite, as a potential funding source for future public green infrastructure projects. The City may also want to evaluate funding sources such as community - based public private partnerships or other funding strategies. Currently, green infrastructure associated with public projects is paid for through the General Fund. Grant will be pursued for projects when the timing of the project and timing of grant proposals allgm Training and Outreach Staff will receive training on green infrastructure planning, Implementation, design, and maintenance via training sessions facilitated or provided by the Clean Water Program. Updates and opportunities for input on the preparation of the Green Infrastructure Plan will be provided to the City of Dublin City Council and City Managers Office on a regular basis. Outreach to the development community and the general public, as necessary, will be conducted in coordination with the Clean Water Program. Compile Green Infrastructure Plan Documentation of the tasks described above will be compiled into the Green Infrastructure Plan for review and approval by the City of Dublin City Council. June 2017 Framepmrk for Green Wrastruolum Plan Development Implement the Green tnfrastructure Plan A resolution, policy, or other legal mechanism will be prepared for adoption prior to beginning implementation of the Green Infrastructure plan. Address the Population -Based IVIRP 2.0 and TMDL Wasteload Allocations The City of Dublin will coordinate with the Clean Water Program, the Bay Area Stormwater Management Agencies Association and the San Francisco Bay Regional Water Quality Control Board (Water Board) to develop a wasteload allocation formula that is based on actual pollutant loadings rather than the current population based formula. Submit Plan to the San Franclsco Say Regional Water Quality Control Board The Plan, and applicable policies or other legal mechanisms for Plan implementation, will be submitted to the Water Board with the City of Dublin's 2019 Annual Report of Stormwater Program Implementation. 4. Timeframe for Plan Development The schedule for conducting specific tasks is presented below. The Green Infrastructure Plan must be approved by City Council by June 30, 2019 and reported to the Water Board in the Annual Report which is due on September 30 each year. Schedule of Specific Tasks Task FY 2016-17 FY 2017-18 FY 2018-19 FY 2019-20 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Identify Projects Develop Tracking Procedures Inca rporate Guidelines Update Planning Documents Evaluate Funding Sources Training and Outreach Compile Plan Adopt Plan LLL I Submit Plan to Water Board Staffing Assignments The Environmental Coordinator in the Public Works Department will direct the preparation of the Green Infrastructure Plan. The Environmental Coordinator will manage consultants hired to assist with the effort and will coordinate with the other City Departments/Divisions that will be June 2017 Frameworkfor Green Infrastructure Plan oevelopmenl an integral part of the Green Infrastructure Plan development including Planning, Engineering, Maintenance, and the City Attorney Office. 6. Budget Development of the Green Infrastructure Plan is estimated to cast approximately $250,000 in consultant costs. Staff has initiated planning level work on the Green Infrastructure Plan in order to inform the preparation of the Framework. Additional work will be required to complete the document. Estimates for design and construction costs of green infrastructure range between $30,000 to $400,000 per treated acre for distributed green infrastructure systems. The cost variation is due to a number of factors such as the location of the project (i.e. if the project is located in a more or less built -out area), the amount of impervious area draining to the green infrastructure facility, and the type of green infrastructure incorporated. The cost for regional facilities is substantially less, ranging between $12,000 - $64,000 per treated acre. The main reason for the price differential comparing distributed facilities to regional facilities is that economies of scale can be achieved with regional facilities. Staff intends to purse options for siting regional facilities in arderto manage both construction and on -going operations and maintenance costs. Estimates for on -going operations and maintenance of green infrastructure facilities range between $1.S0/square foot treatment area lnot including replacement costs] and up to 6% of construction costs. In addition to on -going, regular operations and maintenance, it is anticipated that green infrastructure may need to be replaced every 10 — 15 years. Replacement costs are anticipated to be much less than construction costs since the infrastructure will already have been built; work required will Include removing and replacing vegetation, treatment soil, and underdrain components. The replacement schedule will likely depend on the location of the green infrastructure facility, which will dictate the sediment and pollutant load entering the facility. The cost estimates provided in this section were derived from local Bay Area municipalities, Southern California municipalities, the City of Portland, the City of Tacoma, WA, and the Environmental Protection Agency. Summary The Environmental Coordinator will manage the Green Infrastructure Planning effort required under MRP 2.0 on behalf of the City of Dublin. The City of Dublin will endeavor to construct green infrastructure on public projects where pollutant loads warrant and where funding has been identified. City staff will continue to require private development projects subject to Provision C.3.b of MRP 2.0 to incorporate green infrastructure into applicable projects. City staff will pursue funding options other than the General Fund to assist with Green Infrastructure implementation. The City of Dublin is not committing any funds towards green infrastructure construction with the adoption of this Green Infrastructure Framework; rather, it is committing to initiating the process to complete a Green Infrastructure Plan. June 2017 RESOLUTION NO. xx-19 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DUBLIN *********** APPROVING THE CITY OF DUBLIN GREEN STORMWATER INFRASTRUCTURE PLAN WHEREAS, the San Francisco Bay Regional Water Quality Control Board adopted the Municipal Regional Stormwater National Pollutant Discharge Elimination System Permit (MRP) on November 19, 2015 as Order No. R2-2015-0049; and WHEREAS, the City of Dublin is a permittee under the MRP; and WHEREAS, per the MRP a Green Stormwater Infrastructure Plan must be adopted describing how permittees intend to include green stormwater infrastructure (GSI) in appropriate projects on public and private lands to reduce to the maximum extent practicable adverse water quality impacts due to urbanization and to meet the Total Maximum Daily Loads wasteload allocations for mercury and polychlorinated biphenyls; and WHEREAS, the GSI Plan is intended to describe how permittees, over the long- term, will shift impervious surfaces and storm drain infrastructure from gray, or traditional storm drain infrastructure where runoff flows directly into the storm drain and then to receiving water, to green, which is a more resilient, sustainable system that slows runoff using vegetated systems; and WHEREAS, GSI can provide additional benefits such as mitigating for the urban heat island effect, improving local air quality, reducing localized flooding, providing carbon sequestration opportunities, and improving the streetscape enhancing the bicycle- pedestrian experience; and WHEREAS, the City of Dublin has demonstrated its commitment to an environmentally sustainable future through its policy goals and actions and intends to incorporate GSI into projects when doing so will benefit the environment and when a funding source for GSI has been identified; and WHEREAS, in order to be in compliance with the MRP, a Green Stormwater Infrastructure Plan has been prepared for the City of Dublin. NOW, THEREFORE, BE IT RESOLVED, that the City Council of the City of Dublin does hereby approve the City of Dublin Green Stormwater Infrastructure Plan , attached as Exhibit A. BE IT FURTHER RESOLVED that the City Manager, or designee, is authorized to update the Green Stormwater Infrastructure Plan, including maps and potential project locations, as necessary and identified through an adaptive management process. PASSED, APPROVED AND ADOPTED this 18th day of June 2019 by the following vote: AYES: NOES: ABSENT: ABSTAIN: _____________________________________ Mayor ATTEST: _______________________________________ City Clerk Exhibit A to the Resolution City of Dublin Green Stormwater Infrastructure Plan Use link below. https://dublin.ca.gov/DocumentCenter/View/20762/City-of-Dublin-Green-Stormwater-Infrastructure- Plan