Cherry Valley Dam Spillway Short-Term Improvement Project

The San Francisco Public Utilities Commission is implementing the Cherry Valley Dam Spillway Short-Term Improvement Project in Tuolumne County, California. The project focuses on rehabilitating a segment of the unlined spillway discharge channel to restore its original north-south alignment and properly direct water toward Cherry Creek. This action is necessary because landslide debris has obstructed the channel, causing flows to divert toward public camping areas and the Cherry Power Tunnel Adit entrance. The scope of work includes debris removal, embankment construction, erosion protection, and road improvements, with construction anticipated to last approximately six months starting in June 2026. The project is governed by the California Environmental Quality Act, with a Mitigated Negative Declaration and a Mitigation Monitoring and Reporting Program adopted on January 6, 2026. Key regulatory coordination involves the California Department of Fish and Wildlife regarding endangered species and streambed alterations, the Central Valley Regional Water Quality Control Board for water quality and storm water permits, and Caltrans for traffic impacts and encroachment permits on State Route 120. Special requirements include strict hazardous materials management using secondary containment and onsite spill kits, noise mitigation in compliance with local ordinances, and the potential suspension of work if archaeological resources are discovered. Traffic control measures, including flaggers and non-peak hour scheduling, are required to maintain pedestrian and vehicle circulation.