Prevention against highly destructive golden mussel

All boat launches at foothill reservoirs will remain closed to motorized watercraft as a precaution to prevent the spread of the highly invasive golden mussel. The freshwater bivalves reproduce at an alarming rate, and pose a real risk to NID infrastructure if introduced into local waters.

NID closed all boat launches to motorized watercraft at Scotts Flat and Rollins reservoirs on Dec. 10, 2024, and is awaiting direction from state officials. The District hopes to reopen boat ramps at the reservoirs around late January or early February.

Meanwhile, NID is developing a plan to keep the mussels out of waterways. The plan will likely include an inspection program similar to the District’s quagga and zebra mussels protocols. Read about the program, click here.

On Oct. 17, 2024 the California Department of Water Resources reported finding mature golden mussels at the Port of Stockton. Immediately, state officials called the situation a "significant immediate threat." Once present, the mussels’ infestation can quickly cause devastating damage. The greatest risk is the mussels will be transferred by boats from other waterways. 

“Unfortunately, the golden mussel is able to reproduce at a rapid rate. They could clog a powerhouse as well as get into the canal system and essentially destroy our infrastructure,” NID’s General Manager Jennifer Hanson said.

Other districts and cities are taking action, as well. For example, East Bay Municipal Utility District has temporarily closed boat launches on its Lake Camanche, and the City of Napa has closed the launch and banned boats on Lake Hennessey. Also, the Bureau of Reclamation and Solano County Water District have implemented a 30-day quarantine for all boats entering Lake Berryessa.