Rainbow Water Quality Project
Water Quality Project | Completed August 2026
The project implements green stormwater infrastructure to capture and filter polluted runoff for nutrients, improving surface water quality and protecting local waterways.
Subsurface wetland channels - that include special soil media and plants - filter the water, removing nutrients to improve water quality in Rainbow Creek.
New sidewalks, driveways and curb ramps improve local walkability and connectivity in the area.
Construction began in April 2025 and was completed in August
2026.
Before this project
- Runoff from the street carried pollution into nearby waterways, contributing to water quality issues.
- Absence of curbs and driveways limited vehicular safety.
- Absence of sidewalks between a commercial corner and a park
and school.
After this project
- Planted dispersion and biofiltration basins (rain gardens) filter pollutants from runoff, helping keep waterways clean.
- Curb and driveway improvements increase safety in the area.
- Sidewalk improvements connect the commercial center, park and
school, improving walkability in the area.
Project Details
- This is the County’s largest Green Stormwater Infrastructure project and is located in the Santa Margarita Watershed, which is affected by nitrogen and phosphorous. Learn more about the watershed and water quality on Project Clean Water.
-
Green infrastructure elements within County right-of-way.
This project located within the County's right-of-way installed
subsurface wetland channels to receive runoff and remove pollutants,
such as nitrogen and phosphorous, from stormwater runoff. Native
plants and special soil media clean stormwater by filtering out
pollutants.
- 3,400 feet of subsurface wetland channels were designed to capture and filter stormwater runoff from nearly 345 upstream acres.
- Removing nitrogen and phosphorus from stormwater runoff reduces the pollutant loading to Rainbow Creek and downstream waterways to improve surface water quality and support healthier aquatic ecosystems.
- Storm drain upgrade. This project upgraded existing channels and storm drains to meet present-day needs to limit flooding and ponding in roadways along Huffstatler Street, 5th Street, and Rainbow Valley Boulevard.
- Sidewalks and driveways. This project installed 500 feet of new sidewalk, two ADA-accessible pedestrian ramps, and 27 reconstructed driveways to improve safety, accessibility and local connectivity.
Project Photos
The Santa Margarita Watershed is affected by nitrogen and phosphorous. Learn more on Project Clean Water.
Rainbow County Park
Native plants and soil clean stormwater by filtering out pollutants.
Upgraded channels and storm drains to meet present-days needs to limit flooding and ponding in roadways.
This project replaced 27 driveways within the County's right-of-way.
This project was identified in the Green Streets Clean Water Plan.
Upcoming Events:
There are no upcoming events for this project. Please check back soon.
Learn More:
View our full list of Green Infrastructure Projects
Return to the Watershed Protection Homepage
Sign up for the Quarterly Green Infrastructure Newsletter
The County of San Diego is proud to implement projects like this to improve water quality, support sustainability, and enhance our local communities.
Popular Services