4S Ranch Park Biofiltration Project
Estimated Cost: $500k | Estimated Completion: Fall 2025 | This project is in collaboration with the County of San Diego's Department of Parks and Recreation

Located in the San Dieguito Watershed, this project will improve water quality in Lusardi Creek and the San Dieguito River by removing trash and pollutants from stormwater runoff.
The Sweetwater Watershed is part of the larger San Diego Bay Watershed. Learn how you can limit your watershed impact with our Educational Resources.
Learn more about the San Dieguito Watershed on Project Clean Water.

Green Infrastructure elements will include:
Biofiltration Basin
Biofiltration basins remove pollutants, such as bacteria and debris, from stormwater runoff by allowing the runoff to filter through native plants and soil. It is a natural process that improves water quality and provides benefits such as green space and flood reduction.
Drainage Improvements
The Project will construct surface drainage improvements to direct 1.2-acres of untreated parking lot area into a new biofiltration basin.

Construction: What to Expect
Construction began in June 2025 and is expected to be complete in Fall 2025.
During construction, the County will make every effort to minimize disruptions along the roadways. All construction will occur in the public road right-of-way to avoid impacts to private property owners. There will be temporary impacts to utilities, and to both vehicular and pedestrian traffic. Traffic control measures, including signage placed prior to and during construction, will be implemented to ensure the safety of our customers.
The County of San Diego Project Manager for this project is René Vidales. Contact information for Mr. Vidales is provided below:
- Email: Rene.Vidales@sdcounty.ca.gov
- Phone: (858) 282-1239

Learn about our Other Green Infrastructure Projects
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Visit our Watershed Protection Program Home Page




