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Science for Restoring the Los Angeles River

LA River Master Plan

The County of Los Angeles' LA River Master Plan and the associated Environmental Impact Report are available for public comment until March 14th 2021. Make your voice heard! 

The LA River

Arroyo Seco above Pasadena. Photo by S. Drill
Arroyo Seco above Pasadena. Photo by S. Drill
The 51 mile long Los Angeles River receives rain and snowmelt from the San Gabriel and Santa Monica Mountains as well as the plains of the Los Angeles basin. It flows through a national forest, a national monument, and a national park, as well as through 14 cities and the unincorporated area of Los Angeles County. Thirty-one miles of the river flow through some of the densest urban areas in the City of Los Angeles. Finally, it reaches the sea in Long Beach, draining into the San Pedro Bay. The upper reaches in Arroyo Seco and Tujunga Wash support riparian aspen and willow forests, while much of the middle and lower river exists only in concrete channels. Even here, there are stretches with a natural bottom in Sepulveda Basin, the Glendale Narrows, and along Willow Street in Long Beach where fish, birds, and people spend time in urban nature. 

Fishing with volunteer anglers in the LA River Estuary. Photo by S. Drill
Fishing with volunteer anglers in the LA River Estuary. Photo by S. Drill
Cooperative Extension Advisor Dr. Sabrina Drill conducts research on aquatic habitat, the fish fauna, fishing by neighboring community members, and how climate change is impacting temperature and flow in the river. She uses this information to guide restoration of this important urban ecosystem. 

Fish and Habitat Surveys

We want to hear from you! Because it's difficult to use traditional nets in the urban parts of the river, we rely on collaborations with volunteer anglers. We need your observations to get a robust picture of the the fish community in the river. Please share your catch, or your observations, at our iNaturalist project, Fish of the Los Angeles River/Pesces del Rio de Los Angeles

Researchers from UCCE, Friends of the Los Angeles River, the Resource Conservation District of the Santa Monica Mountains, Aquarium of the Pacific, and CalState LA  have collaborated since 2007 to study the fish community and fish habitat in the river.

Fishing at LA State Park with CSULA. Photo by Sabrina Drill
Fishing at LA State Park with CSULA. Photo by Sabrina Drill

State of the River:The Fish Study (2008)

State of the River: The Long Beach Fish Study (2016)

A Longitudinal Temperature Profile of Fish Habitat in the Los Angeles River

Collaborative Studies

UCCE has participated on a variety of studies led by different agencies. 

Army Corps of Engineers/City of Los Angeles

The Los Angeles River Ecosystem Restoration Project

A Reader's Guide to the LA River Ecosystem Restoration Project

Southern California Coastal Waters Research Project (SCCWRP)

Evaluating the Effect of Changes in Flow and Water Temperature on Stream Habitats and Communities in the Los Angeles/Ventura Region

Environmental Flows for the Los Angeles River (ongoing)

Tiered Aquatic Life Uses in Southern California

The Nature Conservancy

Greenprint for Southern California (ongoing)

Council for Watershed Health/Stillwater Sciences - LA River Fish Passage Opportunities

US Bureau of Reclamation - Low Flow Habitat Features for Urban Channels