Did you know Sacramento River winter-run Chinook have a life-history strategy found nowhere else on the West Coast? However, their population numbers have crashed in abundance from an average of 87,000 spawning adults in the late 1960s to fewer than 200 in the early 1990s. In 2013 30% of the returning winter-run became trapped in the Colusa Basin Drain and were unable to spawn successfully. In late 2015, California Department of Water Resources (DWR) asked Reclamation District 108 (RD 108) to take the lead in developing and constructing the Wallace Weir Fish Rescue Facility in Yolo County, which would block straying fish from entering the Colusa Basin Drain from the Yolo Bypass, and allow California Department of Fish and Wildlife (CDFW) to safely collect and return the fish to Sacramento River to continue their migration. RD 108 selected KSN as the prime consultant for the project, providing project management, grant administration, engineering design, and construction management and inspection for the project. The project consists of a permanent concrete weir structure with bottom hinged dams, a fish barrier, and a fish collection facility. The award-winning facility is a one-of-a-kind, highly complex structure that required extensive collaboration between regulatory agencies, fish biologists, hydrologists, civil, mechanical, hydraulic, structural, and geotechnical engineers, and construction contractors. With funding from State Water Contractors, and with the help of CDFW, DWR, United States Army Corps of Engineers, United States Fish and Wildlife Service, National Marine Fisheries Service, and the Central Valley Flood Protection Board, the RD 108/KSN team took this project from concept to construction in just nine months while navigating a complex planning and regulatory review process. In 2019/2020 over 600 straying fish were collected and returned to the Sacramento River, and the project has become a poster project for how local agencies can collaborate with State and Federal Resources agencies to quickly implement needed salmon restoration projects. To learn more about the innovative efforts Sacramento Valley agencies are advancing to promote salmon recovery go to www.norcalwater.org/efficient-water-management/salmon/.
