Fish Passage Improvement Program

Fish that hatch from eggs laid in freshwater streams, migrate as juveniles to saltwater, mature in the ocean, and then return as adults to spawn in freshwater to complete their life cycle are known as “anadromous.” Populations of anadromous fishes that depend on habitat in the Central Valley, such as, Chinook salmon, steelhead, lamprey, and green sturgeon, have sharply declined. In response to the decline, the National Marine Fisheries Service, the U.S. Fish and Wildlife Service, and the California Department of Fish and Wildlife have listed these species as threatened, endangered, and species of special concern. These natural resource agencies site barriers to migration as a major cause of the decline.

Since 1999, DWR’s Fish Passage Improvement Program has worked to re-open streams and rivers to migratory fishes. Our program is an interdisciplinary team of biologists and engineers who identify and evaluate structures that impede the migration of anadromous fish within the Central Valley. We summarize, describe, and identify fish passage impediments and possible solutions by addressing the problem of fish passage barriers. Through our projects, and collaboration with others, we improve fish passage at these structures by modifying or removing them.

Our work would not be possible without partnerships with CalFish, the California Fish Passage Forum, non-profit organizations, landowners, and other government agencies.

We often form partnerships with agencies and stakeholders to complete fish passage projects. Some projects may be eligible for in-kind services. Contact us for details. DWR provides additional technical assistance.

We plan and implement fish passage projects to modify or remove instream barriers which impede migration and spawning of anadromous fish. Our role differs from project to project.