Speakers at the ribbon-cutting event included Department of Water Resources Director Karla Nemeth; Bureau of Reclamation Acting Regional Director Adam Nickels and California Department of Fish and Wildlife Deputy Director of Public Affairs Katie Talbot. Photo courtesy of the California Department of Water Resources

SACRAMENTO REGION, CA (MPG) - Operations have officially begun for the Big Notch Project, one of the largest floodplain salmon-rearing habitat projects in California history. The Department of Water Resources (DWR) held a ribbon cutting ceremony Nov. 21 in Yolo County to kick off the first operational season of the Big Notch Project.

The project includes three seasonally operated gates at the Fremont Weir, making it easier for juvenile salmon and sturgeon to move into the Yolo Bypass, a critical floodplain habitat that plays a key role in the recovery of these threatened and endangered species.

The Big Notch Project is one of the key actions highlighted in Governor Newsom’s California Salmon Strategy for a Hotter, Drier Future which aims to restore populations of salmon as the state experiences increased temperatures as a result of a changing climate. The project was designed with cutting-edge science and a highly public process that incorporated decades of fisheries research and land-use knowledge. Big Notch will be operated to benefit fish in a way that protects existing land-uses such as agriculture, recreation and flood protection.

“With temperatures warming in California, salmon need rivers that give them more room to roam so they can rest and eat as they migrate to the ocean,” said Department of Water Resources Director Karla Nemeth. “This new infrastructure allows us to better manage how and when river water inundates the Yolo Bypass. This innovative infrastructure helps salmon, protects people from flooding and enables farmers to continue to grow our food in the region.”

The Big Notch Project is built into the Fremont Weir, which is part of the Fremont Weir State Wildlife Area in Yolo County. The construction of the massive project included the removal of a section of the Fremont Weir, the installation of three gates, the excavation of 180,000 cubic yards of material to carve new channels for the salmon, and the construction of a control building and a pedestrian bridge.

With construction now complete, the gated passages will be opened when the Sacramento River is high enough to use the Yolo Bypass as a floodplain. The water will enter the bypass through the notch at Fremont Weir and create a shallow water floodplain for fish to easily migrate through the area. This also means that juvenile salmon will have a food-rich habitat to feed in for a longer time. This creates juveniles that are conversationally called “floodplain fatties,” since studies show the juvenile salmon that feed in floodplains grow rapidly in size, compared to juveniles that only feed in rivers. Floodplain migration also improves their chances of survival as they travel to the Pacific Ocean.

Adult salmon and sturgeon will also benefit from the new openings created from Big Notch’s gates, which will reduce stranding and migratory delays due to passage barriers. Sonar cameras installed at the gates will monitor which species of fish are passing through the Big Notch Project.

The project cost $58 million for construction, oversight and environmental monitoring. Department of Water Resources was able to complete construction of the Big Notch Project, thanks to $41 million in funds provided by project partner and federal lead agency, the U.S. Bureau of Reclamation.

“The Big Notch Project serves as a cornerstone example of how multi-benefit programs can support species recovery and, in turn, ensure a reliable water supply for farms and communities,” said Reclamation Acting Regional Director Adam Nickels. “Reclamation is pleased to partner with the Department of Water Resources in bringing this project from design to operation in support of our shared water interests.”

Said Nemeth, “We are so grateful to all our partners involved in the Big Notch Project, including Reclamation, Yocha Dehe Wintun Nation, California Department of Fish and Wildlife, and National Marine Fisheries Service, as well as Yolo County and the local landowners.”

The Big Notch Project fulfills state and federal regulatory requirements to support endangered species for continued operation of the State Water Project and federal Central Valley Project. The State Water Project provides water to 27 million Californians, 750,000 acres of farmland, and businesses throughout the state. The Central Valley Project provides an annual average of 7 million acre-feet of water for farms, 600,000 acre-feet of water for municipal and industrial uses, water for wildlife refuges, maintains water quality in the Sacramento-San Joaquin Delta, and reduces flood risk for the Central Valley.

Following the ribbon-cutting event, attendees had an opportunity to watch Gate 1 of Big Notch open and water flow through as well as take a walking tour to the new pedestrian bridge and control building.