Connecting the Drops in Santa Clara Valley - Stormwater Capture Project Identification, Prioritization, and Concept Design to Facilitate Green Stormwater Infrastructure Planning
The Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP), an association of thirteen cities and towns in Santa Clara Valley, the County of Santa Clara, and the Santa Clara Valley Water District, has begun development of a Stormwater Resource Plan (SWRP) for the Santa Clara Basin. One goal of the SWRP is to develop an integrated approach for SCVURPPP agencies to implement green stormwater infrastructure (GSI) on a watershed-scale. Under the Bay Area Municipal Regional Permit (MRP), each SCVURPPP agency is required to develop and implement a long-term GSI Plan that describes how the agency will identify and implement local GSI projects. The SWRP supports these efforts by identifying and prioritizing multiple benefit GSI projects and to position these projects for funding through state grants or agency partnerships.
As part of the SWRP, a GIS-based screening and prioritization method was used to evaluate project opportunities that were identified for the portion of the Santa Clara Basin within the boundaries of Santa Clara County. The screening and prioritization method was developed with input from all agencies through a cooperative effort, ensuring that local and regional priorities are addressed. Potential sites were screened based on factors such as available area, land ownership, and slope that would determine if a site was feasible for public GSI implementation. Using a metrics-based scoring approach, the screened opportunities were then evaluated and ranked based on each site’s potential to support a GSI project that achieves a range of benefits (water quality, water supply, flood management, environmental, and community benefits). The resulting prioritized list of opportunities provided useful information for the development of each agency’s local GSI Plan, which could then be combined with additional information on local priorities for types and locations of projects.
From the list of prioritized project opportunities, 23 high-ranking projects were selected for further quantification of project benefits (stormwater volumes captured and pollutant loads reduced) using a hydrologic model. Following field reconnaissance, concept designs were then developed for 12 projects to explore feasibility of implementation and serve as a platform to discuss funding opportunities with possible partner agencies or to apply for state grants.
This presentation will provide an overview of the approaches used to develop the SWRP, discuss methods for identifying and prioritizing opportunities for GSI implementation, and illustrate use of project concepts to promote and obtain GSI funding. An example of how the SWRP results and concepts were integrated into a local GSI Plan will be provided. The audience will gain insight into the level of coordination required to develop a SWRP that meets the needs of all stakeholders, the benefits of concept designs for positioning agencies for funding, and how agencies can coordinate local efforts to meet regional goals. The presentation supports the conference theme by showing how identifying opportunities for stormwater capture in a SWRP can align with meeting stormwater permit compliance goals and achieve multiple benefits.