Application of watershed-scale habitat modeling and decision-support tools for reservoir reoperations in coastal northern California

Water managers must often balance the needs of both aquatic habitat and human water supply. However, they frequently only have tools to manage delivery alone. Existing modeling for gaps in providing detailed biological estimates at a watershed scale simulating supply operations suitability simultaneously. A new platform calculation framework, Aquatic Habitat Assessment, was applied case study quantify fish passage local species Chinook salmon ( Oncorhynchus tshawytscha ) steelhead trout mykiss ). Assessment coupled with suite tools, including HEC-RAS used hydraulics, WEAP allocations, Tableau visualization. The ensemble simulate utility system near San Francisco Bay California evaluate effects reservoir reoperations on habitat. successful bringing range conflicting parties coalesce around common solution operations. Two sets alternative operation schemes were developed, which largely involve higher winter lower summer releases, aligning more closely natural Mediterranean patterns functional flows connected species. Results tradeoffs across schemes, modeled increased under reoperations, but decreased. spawning, incubation, rearing during release period decreased period.