The 689 square mile South Fork Eel River watershed, located within Mendocino and Humboldt counties, is one of five priority stream systems selected as part of the California Water Action Plan effort. Periods of low flow limit the hydrologic connectivity of the riverine habitat and raise water temperatures. This is of critical concern for at risk salmon and steelhead species which reside in the watershed including the Southern Oregon/Northern California Coast Coho Salmon, California Coastal Chinook Salmon, and North Coast steelhead. To address the California Water Action Plan, the Department has conducted several studies in the South Fork Eel River watershed. Watershed-wide flow criteria were determined using a combination of site-specific methods and functional flows to support steelhead life stages, maintain natural flow patterns, and support the ecosystem throughout the watershed. The study in Redwood Creek used a one-dimensional modeling approach to combine data on river hydraulics, species- and life-stage-specific habitat preference, and physical habitat modeling to determine instream flow needs for rearing salmonids. Site-specific habitat suitability criteria were developed through extensive surveys in Hollow Tree Creek, tributary to the South Fork Eel River. The South Fork Eel River study components are complete and technical reports, appendices, calibration reports, and supporting materials are available below. Resources Watershed-Wide Instream Flow Criteria for the South Fork Eel River (PDF)(opens in new tab) Instream Flow Evaluation: Juvenile Steelhead and Coho Salmon Rearing in Redwood Creek, Humboldt County (PDF)(opens in new tab) Appendices to Instream Flow Evaluation: Juvenile Steelhead and Coho Salmon Rearing in Redwood Creek, Humboldt County (PDF)(opens in new tab) Hydraulic Model Calibration Report for Instream Flow Evaluation: Juvenile Steelhead and Coho Salmon Rearing in Redwood Creek, Humboldt County (PDF)(opens in new tab) Habitat Suitability Criteria for Juvenile Salmonids in the South Fork Eel River Watershed, Mendocino and Humboldt Counties (PDF)(opens in new tab) Appendices to Habitat Suitability Criteria for Juvenile Salmonids in the South Fork Eel River Watershed (PDF)(opens in new tab) Redwood Creek Flow Monitoring and Unimpaired Flow Estimation Report (PDF)(opens in new tab) South Fork Eel River Study Plan (PDF)(opens in new tab) Click map to enlarge.
Instream Flow Program Instream Flow Studies Big Sur River Butte Creek Clear Lake Watershed Deer Creek Mark West Creek Mill Creek Scott River and Shasta River South Fork Eel River Ventura River California Water Action Plan Watershed-Wide Instream Flow Criteria Instream Flow Criteria Map Instream Flow Program Documents Instream Flow Quality Assurance Program Instream Flow Program Presentations External Instream Flow Resources Hollow Tree Creek (South Fork Eel tributary) Redwood Creek (South Fork Eel tributary)