For over 60 years, the San Joaquin River saw no adult spring-run Chinook Salmon make their annual migration from the ocean to spawn – the fish had been cut-off from their native spawning grounds by Friant Dam and subsequent water diversions that dried up over 60 miles of channel. Chinook Salmon runs had been extirpated from the San Joaquin River upstream of the Merced River confluence. But all of that changed in 2019 when the San Joaquin River Restoration Program (SJRRP) documented its first returning adult spring-run Chinook.
A main goal of the SJRRP is to restore fish and flows back to the San Joaquin River above the Merced River confluence to maintain a self-sustaining, naturally reproducing Chinook salmon fishery. One of the initial projects to help the SJRRP achieve this goal is the Eastside Bypass Fish Passage Improvement Project (Project). The Eastside Bypass Control Structure (EBCS) is within the Eastside Bypass and is part of the State’s flood bypass system (see map of the Restoration Area). The EBCS is a partial fish passage barrier. The objectives of the Project include installing a full-width rock ramp roughened channel below the EBCS and modifications to the EBCS to improve fish passage, while retaining its ability to provide flood control. Modifications to the EBCS to provide fish passage include removing a portion of the sill, half of the energy dissipation blocks within the four center bays, and 4-foot-high stop logs on the upstream side of the EBCS. In addition, an approximately 380 foot-long rock ramp will be constructed downstream of the structure to provide suitable passage from the downstream pool to the structure. These elements will allow passage for salmonids and improve passage for other native fish such as sturgeon and lamprey fish to move more easily through the EBCS with minimal impacts to the structure, as well as not require extensive operation or maintenance. Improved passage at the EBCS especially during drought conditions will help rebuild native fish populations in the San Joaquin River.
Human Interest/Community Benefit:
The population of White Sturgeon occupying the Sacramento-San Joaquin River basin is recreationally fished (bag limit of 3 White Sturgeon per year between 40-60 inches) except for a few reaches. Increasing access to additional spawning and rearing habitat in the upper San Joaquin River will thus enhance the existing White Sturgeon fishery. The proposed project would be constructed on land managed by DWR and would not provide any public access structures. However, construction of the fish passage project at EBCS and improvement projects throughout the Eastside Bypass would allow for release of increased flows upstream and access to higher quality habitat for native fishes in the SJRRP Restoration Area. In this way, the project could aid public access to recreational opportunities. This project will conduct outreach and education to the local and regional community through the following activities: SJRRP biennial Science Meeting presentation (anticipated Fall 2024) which may include participants from the public (the Friant or Fresno community if in-person or the broader public if virtual), water operators and agricultural interests, and tribes; and a featured story in the FWS Pacific Southwest Highlights online. The project will also be chronicled on the SJRRP website.
Project Timeline:
Estimated construction completion in October of 2024