DWR ensures operations at Oroville Dam meet environmental compliance objectives. It develops, conducts, and manages fisheries research and monitoring studies to inform proper management and restoration actions in coordination with partner entities and agencies. DWR has also led studies to inform the feasibility of reintroducing spring-run Chinook salmon to headwater habitat in the North Fork Feather River above Lake Almanor.

Chinook salmon and Central Valley Steelhead

Adult Chinook salmon and Central Valley steelhead abundance are monitored through escapement surveys, which refer to the number of adults that escape the ocean and return to a river to spawn. Escapement can be estimated from a combination of hatchery broodstock tagging, redd (spawning nest) surveys, carcass surveys, and video-monitoring through the Feather River Fish Monitoring Station.

DWR collects data on juvenile Chinook salmon and Central Valley steelhead through emigration monitoring with rotary screw traps, beach seine, electrofishing, and visual snorkeling surveys. These methods study the effect of environmental factors on emigration, such as flow, turbidity, and water temperature and examine the distribution, relative abundance, and habitat preference of Chinook salmon, steelhead, and their predators.

North American Green and White Sturgeon

North American Green and White Sturgeon are monitored in the Feather and Yuba Rivers through sonar surveys, acoustic tagging, and in-river egg and juvenile collection. Specialized Adaptive Resonance Imaging Sonar (ARIS) uses sound waves to produce near video quality images to identify sturgeon with their unique size and shape. Once sturgeon are located, scientists capture and surgically implant an acoustic transmitter in the sturgeon before releasing them back into the river so they can be tracked without future handling. Acoustic tags emit a unique identifier that can be “heard” using stationary or mobile receivers. Additionally, scientists deploy egg collection mats and larval nets each spring to document evidence of sturgeon spawning in the river.

Habitat improvement and restoration projects on the Feather River enhance ecological conditions to support native fish species, particularly Chinook salmon and steelhead. Projects aim to reestablish natural river processes, improve fish passage, and increase spawning and rearing habitats. Efforts completed include spawning gravel augmentation and enhancement, side channel maintenance, and floodplain reconnection. These efforts not only improve water quality and habitat complexity but also promote the long-term resilience of aquatic ecosystems in the lower Feather River.

Spawning Gravel Enhancement Projects

Migratory fish species rely on Feather River spawning habitats along the low-flow channel, where most spawning activity occurs. Female salmonids lay their eggs in nests called “redds” using coarse sediment, such as clean, rounded gravel. From 2014-2023, DWR has added approximately 22,300 cubic yards of spawning gravel in the river to replenish material that is naturally carried downstream during high flow events. Access to existing side channels in the river for salmonids was also improved by excavating and redistributing accumulated streambed material. With improved spawning habitat, DWR has observed significantly higher rates of Chinook spawning in the Feather River.

The Feather River in Oroville offers a wealth of recreational and community engagement opportunities, blending outdoor adventure with environmental education. Through DWR’s Feather River Floating Classroom, people of all ages learn about the salmon lifecycle and critical ongoing conservation efforts and research in the Feather River.  The program gives students and participants an up-close and personal view of Chinook salmon, as rafts guided by DWR Environmental Scientists drift through their natural spawning habitat. Free tours occur in October and November during the fall spawning season.

The Feather River Fish Hatchery, located in Oroville, California, was built in 1967 by DWR to mitigate for the loss of salmon and steelhead spawning and rearing habitat due to the construction of Oroville Dam, power generation facilities, and associated components (Oroville Complex). Operated under contract by the California Department of Fish and Wildlife (CDFW) and owned and maintained by DWR, the hatchery raises millions of spring-and fall-run Chinook salmon and steelhead smolts and fingerlings each year, which are released into the Feather River.

To maintain genetic integrity, DWR develops Hatchery Genetic Management Plans (HGMPs) for each of its programs: spring-run Chinook salmon, one of the few remaining sub-populations in the Sacramento Valley; fall-run Chinook salmon; and Central Valley steelhead. The Feather River Fish Hatchery plays a vital role in supporting Chinook salmon and steelhead populations in the Feather River and remains a cornerstone of California's fishery management and conservation initiatives.

DWR provides guided tours of the Feather River Fish Hatchery. Hatchery visitors can observe salmon migrations through the underwater viewing windows from mid-September to June, witness spawning operations during the fall and winter months, learn about salmon ecology, and feed juvenile salmon in the rearing raceways. Hatchery tours are available by reservation through the Lake Oroville Visitor Center at (530) 538-2219.