San Joaquin County proclaims local emergency over invasive golden mussel

San Joaquin County supervisors proclaimed a local emergency on Tuesday over the threat of the golden mussel in the San Joaquin Delta. 

The local emergency calls for strengthening state partnerships, coordinating funding, mitigation strategies and infrastructure protection. Supervisors are set to review the emergency status every 60 days. 

Supervisors also agreed to coordinate response to protect boating access, fishing, public infrastructure, farms and freshwater systems throughout the region. 

Officials say the golden mussel can quickly colonize surfaces, clog pipelines, restrict water flow and disrupt natural habitats. They pose a risk to water conveyance systems, flood control infrastructure, agriculture, recreation and the delta ecosystem. 

"We appreciate the State's partnership, but prevention alone is not enough where this species is already established," supervisor Paul Canepa said in a statement. "This declaration should serve as a warning across California that we need targeted solutions for the Delta and a serious conversation about mitigation."  

Gov. Gavin Newsom's office said the challenge requires a "sustained commitment rather than short-term emergency measures."

"The Newsom administration is committed to protecting both statewide water infrastructure serving 27 million Californians and Delta ecosystems and communities," a spokesperson for Newsom said. "We're staying in close contact with county officials to ensure their concerns shape our statewide strategy and to provide ongoing technical and financial support."

Assemblymember Rhodesia Ransom, who represents the area, is also pushing a proposal that includes funding for five decontamination stations along the delta, with $1.5 million allocated to each site. 

The bill also aims to streamline the permitting process that slows down the coordination between water agencies and the California Department of Fish and Wildlife, allowing for faster inspections and boat cleaning.

The first detection of the golden mussel in North America was in the San Joaquin Delta in 2024.   

Since then, mandates have been put in place at lakes across Northern California, including Lake Tahoe. The mandates require boats to go through an inspection and quarantine process in order to prevent the golden mussel from spreading.