Advancing Regional-Scale Stormwater Management in San Mateo County
In 2019, C/CAG received approximately $3M from a State General Fund Grant administered by the California Natural Resources Agency to advance a collaborative approach to regional-scale stormwater management in the county. This effort evolved from C/CAG’s earlier planning efforts to identify and prioritize stormwater capture and green infrastructure projects throughout the county and at different scales (parcel, street, regional), staring with the Countywide Stormwater Resource Plan (2017), which evaluated at the highest level priority locations for all scales of green infrastructure, followed by the Countywide Sustainable Streets Master Plan (2021), which took a closer look at the highest leverage opportunities to integrate green stormwater infrastructure into already planned active transportation improvements and newly identified intersection improvements near schools and transit-hubs with the overall goals of improving water quality, increasing resiliency against climate change and advancing active transportation goals with respect to safety, accessibility an public health.
At the regional or watershed scale, C/CAG’s green infrastructure modeling work, aimed at demonstrating how municipalities in the county would achieve longer-term pollutant reduction goals, also proved that working across jurisdictions, and planning projects in a way that maximized water quality and other community and environmental goals (including reduced capital and operations costs, as well as the potential to increase groundwater recharge, reduce flood risk and manage larger volumes through regional-scale infrastructure projects) was a wiser planning approach from all angles.
Regional Collaborative Program Framework
Leveraging the $3M in State funds and an additional grant of $500K from the US Environmental Protection Agency awarded to the San Mateo County Office of Sustainability to advance regional multi-benefit projects, C/CAG, the Office of Sustainability and the newly formed Flood and Sea Level Rise Resiliency District (OneShoreline) set out to advance regional stormwater capture project designs for three already identified/prioritized sites (Red Morton Park, Redwood City; I-280/I-380 Interchanges, San Bruno; Twin Pines Park, Belmont), create five new design concepts for the next round of high priority regional projects and develop a business case for regional collaboration on stormwater management in the county. Additionally, C/CAG received pro-bono technical support from American Rivers and Corona Environmental to develop a stormwater credit trading feasibility analysis in the county and from the WaterNow Alliance to evaluate innovative funding and financing options to fund future projects. This multi-part project culminated in a Regional Collaboration Program Framework White Paper, which provides the foundation for C/CAG’s member agencies and partners to further explore creating a collaborative program, as well as to set up the institutional components of cost-sharing on projects, exchanging stormwater “benefit units” for NPDES permit compliance and other goals, and for growing the program into a broadened “market-based” system for incorporating more eligible entities, more project types and a greater diversity water quality, climate resiliency and community benefits for exchange. The full Regional Collaborative Program Framework White Paper and Appendices, including the multi-part analyses mentioned above, are available for download below.
Region Collaborative Program Framework White Paper + Appendices
Download the Regional Collaborative Program Framework White Paper Appendices below:
A. Advancing Regional-Scale Stormwater Management in San Mateo County: Drivers and Objectives
D. Assessing the Feasibility of Stormwater Credit Trading in San Mateo County, CA
E. Funding and Financing Countywide Green Stormwater Infrastructure Investments
Regional Project Study Memo & Project Design Concepts
To help lead towards funding and building regional multi-benefit stormwater capture projects, the outputs from the opportunity identification and prioritization assessment were compiled in a comprehensive Regional Project Study Memo, which summarizes the analysis of site opportunities and includes the site visit assessment report and recommendations for developing five regional project preliminary design concepts. The Regional Project Study Memo also includes the full summary of statistics for the top ranking sites and the overall list of identified opportunities. The memo also incudes the full opportunities identification and prioritization analysis as an attachment.
With additional input from C/CAG’s member agencies and potential regional project partners, including Caltrans and the Jefferson Elementary School District in the Broadmoor area of Daly City, five preliminary design concepts were developed with additional funding from the U.S. Environmental Protection Agency Water Quality Improvement Fund for the S.F. Bay Area awarded in 2019 to the County Office of Sustainability. The five selected sites were based on the Regional Project Study Memo detailed above with several modified locations based on additional stakeholder input and technical analysis.
Download the Regional Project Design Concepts below: