Quagga and Zebra mussels are harmful, highly invasive freshwater species recently discovered in California waters. California’s resources agencies have stated that the further spread of Quagga or Zebra mussels in California waters may result in an environmental and economic disaster. Learn more about the mussel invasion. Visit Quagga and Zebra Mussels Incident Description.
Current infestations in California are limited to Quagga in several Southern California reservoirs that receive water from the Colorado River. There is one Zebra mussel infestation at an isolated reservoir in San Benito County. Access the map. Visit Zebra and Quagga Mussel Sightings Distribution.
The appearance of the mussels has heightened concern that they may infest other California waterways.
Recent California legislation added a requirement to the California Fish and Game Code. Owners and managers of reservoirs must assess the vulnerability of their reservoirs for the introduction of nonnative dreissenid mussel species, such as Quagga and Zebra. They must develop and implement a program designed to prevent the introduction of these mussel species.
In waters outside their native range, Quagga and Zebra mussels are harmful, highly invasive freshwater species. Favorable growing conditions and the absence of natural predators contribute to their rapid colonization and expansion. Quagga and Zebra mussels can have significant negative impacts on the natural environment, including:
PG&E operates many lakes and reservoirs for public recreation and producing clean, renewable hydroelectricity. The effects on personal and public property infested with Quagga and Zebra mussels can include:
Get more information about public recreational facilities. Visit Another benefit of Hydropower.
To protect our assets and the ecological integrity of the waters we manage, and to comply with AB 2065, we began implementing an infestation prevention program for our reservoirs and waterways in 2009. The program includes public education, monitoring and management of permitted recreational, boating and fishing activities. We work with local, state and federal agencies, other utilities and recreational facility operators to ensure that the program is effective. The program includes the following elements to help prevent the infestation of Quagga and Zebra mussels:
Quagga and Zebra mussels can clog water pipes, coat piers and ruin boat motors. Transferring a boat from an infested body of water to another may spread the mussels. Boaters must check their boats, trailers and vehicles each time they take the boat out of a lake or reservoir.
When leaving the water:
Report sightings of Quagga and Zebra mussels by calling the California Department of Fish and Game Quagga and Zebra Mussel Hotline: 1-866-440-9530.
Get more information about helping to prevent the invasion. Visit California Department of Fish and Wildlife Quagga and Zebra Mussels.
We appreciate your vigilance and support to keep California’s waters free of invasive mussels.
Get more information about invasive species from the following Web pages: