Instream flow Analysis – Shasta River

The precipitous decline of salmon and steelhead populations throughout the state of California is attributed to numerous factors, some of which include; water supply, water quality, habitat destruction, and blockages to fish migrations.  The instream flow projects are designed to look at one aspect of the myriad of issues plaguing salmon populations, water quantity.  There are three instream flow projects the OPC approved statewide, they include; the Shasta River, the Big Sur, and the Santa Marina River.

Each of the rivers were chosen based on a list of twenty-two priority streams that require instream flow analysis throughout the state.  (This list is exhibit 2 of the staff recommendation, linked below).

This list was developed with input from regional DFG staff, water board staff, U.S. Fish and Wildlife Service, and NOAA national marine fisheries service.

In developing the list of priority rivers, DFG staff considered criteria such as; 1) presence of anadromous species, 2) likelihood that DFG flow recommendations would provide a high level of improvement, 3) availability of recent flow studies or other relevant data, and 4) the possibility of partners and willing landowners to work with staff on these assessments.

Completion of these projects satisfies many goals and priorities for the OPC, including the goal to significantly improve the quantity and quality of ocean and coastal habitat in California, specifically to work toward monitoring and measuring stream flows on key coastal streams as well as to determine the flow rates necessary to protect water quality in coastal lagoons and estuaries.

The Shasta River project will focus on two reaches of the river including the mainstem canyon reach and a tributary to the main stem which is known as the little Shasta River.

Some of the tasks for this project will include outreach with the local community, development of unimpaired and regulated hydrographs and thermographs, development of habitat-flow relationships, and basin wide integration of the stream flow analysis.  The completion of all the projects will aim to provide an increase in habitat for salmonids.

Final Report

Final Report: Shasta River Big Springs Complex Interim Instream Flow Needs Assessment

The OPC has approved a grant to Humboldt State University for $300,000

The Department of Fish and Game
The State Water Resources Control Board
Humboldt State University


The research gained from this project will help identify the quantity of water, what temperature, and flow that is required for salmon and steelhead species to properly mature in freshwater environs.  The data gathered will hopefully lead to an increase in available habitat and water supply for these endangered species.

The result of the instream flow analysis will be provided to the State Water Resources Control Board by the Department of Fish and Game in the form of flow recommendations for the Shasta River.

Council Documents

Instream Flow Staff Recommendation

Related Projects
Big Sur Instream Flow Project
Santa Maria Instream Flow Project
CEMAR Southern Steelhead Resources Project

Categories: Aquaculture