Many of California’s rivers and streams are known for the salmon and steelhead trout that begin and end their life cycles in them. To protect these anadromous fish, studies are needed to better understand their habitat requirements. This is especially important in stream systems where conditions are altered from natural historic levels and where changes negatively affect the timing of flow distribution and temperature regimes. Instream flow studies are developed to assess the amount and timing of water flow, and study reports are generated that summarize the data collected in order to recommend flow regimes required to maintain healthy aquatic resources.
Flow studies are intended to inform water managers about the flows needed for fish rearing, spawning, and/or migration, habitat suitability, or to provide a full complement of study planning information for future instream flow work. Click the links below to learn more about current and completed IFP projects, including the development of instream flow criteria for watersheds throughout the state. Historical flow recommendations submitted to the State Water Board are also available, and can be viewed using the interactive map.