Project A.4 – Eliminate Adult Attraction Into the Colusa Basin Drain

Project is Complete   

The migration of adult Chinook salmon into the Colusa Basin Drain, where they were then trapped, was widely reported for many years by agency personnel and stakeholder groups. In 2012 an estimated 600 adult winter-run were trapped in the drain. A massive recovery effort was undertaken but the results were doubtful. Development of a blocking barrier or some other way to keep the fish out of the drain became a high priority. Fisheries scientist Dave Vogel developed an engineered slanted screen proposal and Reclamation District 108 headed by Lewis Bair stepped forward to fund and implement it. State and federal agencies approved the design and construction was started in September of 2015. The large project was completed in late November of 2015. Further structural problems emerged after the wet winter of 2017 which were eventually addressed and fixed.

In addition, the problem of adult salmon returning to spawn by way of the Yolo Bypass has also largely been addressed.  A capture facility was built in the Bypass at Wallace Weir.

Additional Resources

Video demonstrates structural fix at Knights Landing Outfall Gates

Wallace Weir Fish Capture Facility