The California budget signed this week by Gov. Gavin Newsom includes $6 million to help fight the spread of golden mussels across the state’s waterways.
The pesky mollusks were first discovered in the Port of Stockton two years ago and are now clogging pipes and fouling water systems far and wide.
The state action comes in addition to efforts on the federal level, where bills in the House and Senate seek to bring more aid to stop the quick-spreading invaders.
The funds will go to support decontamination sites for boats and equipment in the Delta to try to keep the mussels from reaching more lakes and rivers across the state, said Assemblymember Rhodesia Ransom, D-Tracy. So far, the efforts have seemed like a losing battle, with the invasive species reaching deep into California and a decision to give up the fight in Lake Oroville.
“This funding brings critical state support to San Joaquin County and the Delta, where our communities have been experiencing the impacts of golden mussels since day one,” Ransom said in a statement. “Without urgent action, golden mussels will continue to spread through California waterways, and families will bear the cost of this crisis through higher water rates and increased food prices.”
The money comes as U.S. Sens. Alex Padilla and Adam Schiff, both California Democrats, jointly introduced the Golden Mussel Eradication and Control Act of 2026. U.S. Rep. Josh Harder, D-Tracy, authored a similar measure last year in the House. The bills are aimed at bringing federal dollars to fight the problem.
Golden mussels, believed to have been deposited in the Port of Stockton from ballast water on a ship arriving from Asia, are now threatening the Delta’s water systems.
After learning of the encrustment of local water-system intakes, the Stockton City Council approved an emergency declaration, making the city eligible for state and federal reimbursements. That followed a similar action by the San Joaquin County Board of Supervisors in April.
The bivalves are causing water-quality issues as well.
“Golden mussels pose a threat to our water infrastructure by rapidly infesting our waterways across the state and releasing byproducts like nitrogen and phosphorus that can cause harmful algal blooms,” Padilla said in a statement.