Aquatic Pesticide Applications in the SWP in 2025

DWR's Operations and Maintenance staff will be applying aquatic pesticides to several facilities throughout the State Water Project (SWP) in 2025. Treatments will occur on an as-needed basis to control invasive mussels. The pesticides to be used may include copper, chlorine, and/or Pseudomonas fluorescens, strain CL145A based compounds.

Locations throughout California to be treated include, but are not limited to, North Bay Aqueduct, Clifton Court Forebay, Dyer Reservoir, Patterson Reservoir, South Bay Aqueduct, Lake Del Valle, O'Neill Forebay, San Luis Reservoir, Los Banos Reservoir, California Aqueduct, Coastal Branch Aqueduct, West Branch Aqueduct, Quail Lake, Pyramid Lake, Castaic Lake, Castaic Lagoon, East Branch Aqueduct, Silverwood Lake, and Lake Perris. Most of these locations do not have populations of invasive mussels as of the date of this notice but are included because they are at risk of invasive mussel infestation and could become infested during 2025.

Public access to SWP water bodies will be restricted during aquatic pesticide treatments and notifications will be posted at the site. For questions, contact Tanya Veldhuizen at Tanya.Veldhuizen@water.ca.gov