Santa Margarita River – Sandia Creek Fish Passage

Santa Margarita River – Sandia Creek Fish Passage

Home | Key Initiatives | Reconnect Habitat | Santa Margarita River – Sandia Creek Fish Passage

Project Goal:

Remove a high priority fish passage barrier, improve trail user experience and safety, protect the public from flood impacts, and increase the quality of riparian and river habitat for multiple species. 


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Project Stages

35% Planning and Design

65% Planning and Design

100% Planning, Design, and Permitting

Implementation

Post-Restoration Monitoring

Estimated Completion Date:
2025 construction; 2027 completion

Region:

Project Funders

NOAA

CDFW

Coastal Conservancy

California Natural Resource Agency

California Fish Passage Forum

State of California Wildlife Conservation Board

Fish Affected:

Project Description

The Santa Margarita River is one of our high priority rivers targeted for restoring anadromous steelhead populations. As one of the few perennial rivers in Southern California, it offers a prime opportunity to support our most resilient native species - the endangered Southern steelhead - with complete headwaters-to-ocean watershed access. It is lightly impacted by urbanization over 27 miles and has a spring creek-like character in the upper watershed, protected in the Santa Margarita Ecological Preserve. The Santa Margarita River historically supported steelhead and still has natural channel characteristics necessary for migration and propagation of the species.

However, fish passage barriers have prevented steelhead from accessing upper reaches of the river that contain good spawning and rearing habitat. The proposed fish passage barrier remediation project in the Santa Margarita River is one of the most tractable projects in Southern California that can provide passage for steelhead to quality habitat within 5 years. Removal of the fish passage barrier at the Sandia Creek Drive bridge and replacement with a new bridge will provide juvenile and adult steelhead access to 12 miles of upstream habitat. The replacement bridge will also provide much needed flood control in this high-usage public thoroughfare, improving safe passage for thousands of cars every day – including residents and commuters to Camp Pendleton’s Fallbrook access.

When construction started in 2023, inadvertent cultural discoveries caused the project to pause as other alternatives were considered. State and federal funders, landowner The Wildlands Conservancy, and CalTrout supported pivoting the bridge alignment to honor the tribal request to avoid the culturally sensitive area. The civil and structural re-design plans are finished and reviewed by San Diego County. Construction will re-initiate in September 2025 next to the existing river crossing, and the new steel bridge will be completed in May 2027. The old flood-prone box culvert structure will be demolished after the new bridge is completed. Trails of the Santa Margarita Trail Preserve and Sandia Creek Drive river crossing will remain open during construction.

Project Partners:

The Wildlands Conservancy

County of San Diego

National Marine Fisheries Service.

Trout Unlimited

NOAA

California Dept. of  Fish and Wildlife

State Coastal Conservancy

CA Natural Resources Agency

Wildlife Conservation Board

Pechanga Band of Indians

Project Team

Engineering Firms KPFF and River Focus

Leighton

Dudek

Gannett Fleming

Granite Construction Company

Stinger Bridge and Iron

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