California commits $7.5M to fight golden mussels in Sacramento Delta waterways
California is investing $7.5 million to slow the spread of invasive golden mussels, including $6 million in one-time funding and $1.5 million in ongoing annual support to protect the state’s waterways and water infrastructure.
The golden mussel, a freshwater mollusk native to Southeast Asia, was first detected in North America in the Sacramento-San Joaquin Delta in October 2024. In the nearly two years since, the species has proliferated statewide, with sightings as far as San Diego and, most recently, at the Port of West Sacramento.
Its tendency to rapidly reproduce, forming dense colonies on underwater surfaces, can clog pipes, pumps and critical water infrastructure while disrupting local ecosystems. Its spread has raised resulting alarm across California: over the past two months, the Sacramento, Kern and San Joaquin counties have declared local emergencies in response to the invasive species threat.
The 2026-27 state budget includes $6 million in one-time spending and $1.5 million in ongoing annual support to combat the golden mussel infestation. The money will establish five Delta-based decontamination sites to inspect boats and equipment for invasive mussels and remove them before they spread to other waterways, Assemblymember Rhodesia Ransom, D-Tracy, said.
“We’re working to create urgent action because without that we know the mussels are continuing to spread and impact our waterways,” Ransom said in an interview. “We just want to make sure families and businesses aren’t bearing the cost of this crisis.”
According to the California Department of Fish and Wildlife, the mollusk can attach itself to watercraft and equipment, “hitchhiking” between water bodies, which it then infests. Its proliferation in waterways that serve State Water Project facilities, such as the Delta, is of particular concern, Ransom said.
Some 30 million Californians rely on the Delta for water, and damaged water infrastructure would increase maintenance costs and water rates, she said.
Beyond the “instant relief” funding — which Ransom said could be released as early as this month pending the governor’s sanction — Ransom authored AB 2032, the Golden Mussel Response Act, to “remove the roadblocks” to respond to the invasive species’ spread.
“I’ve already heard about agencies facing delays,” Ransom said, citing a “lengthy” permit process. The bill would establish an expedited permit process to combat the golden mussel’s proliferation, allowing officials to move “at the speed of the mussels,” Ransom said.
How can I check my watercraft for golden mussels?
As state and local action to contain the spread of the mussels goes underway, officials encouraged boaters to check their boats for the mussels, following “clean, drain and dry” procedure:
- Clean off visible aquatic plants, animals and mud from equipment before leaving water access.
- Drain water-containing devices before leaving water access.
- Dry everything for at least five days or wipe with a towel before reuse.
- Dispose unwanted bait, worms and fish parts in the trash and use spring or dechlorinated tap water to store live bait.
Any sightings of the golden mussel should also be reported to the CDFW online at its Report an Invasive Species Sighting webpage, via email Invasives@wildlife.ca.gov, or by calling 866-440-9530.
