The growing threat of golden mussels — an invasive species harming the Delta ecosystem with a potential to undermine water delivery systems — prompted the San Joaquin County Board of Supervisors Tuesday to declare a local emergency.
Supervisors are urgently calling for strengthened State partnership, additional resources, and coordinated action to protect the Delta — one of California’s most vital waterways.
The golden mussel poses serious risks to water conveyance systems, flood control infrastructure, agriculture, recreation, and the Delta ecosystem.
Officials warn the species can rapidly colonize surfaces, clog pipelines, restrict water flows, and disrupt natural habitats.
“The Delta is central to San Joaquin County’s identity, and with more than two thirds of the Delta within our county, protecting it must remain a top priority,” said Supervisor Paul Canepa.
“We appreciate the State’s partnership, but prevention alone is not enough where this species is already established. This declaration should serve as a warning across California that we need targeted solutions for the Delta and a serious conversation about mitigation.”
The Delta is a critical source of drinking water, agricultural production, economic activity, and recreation for San Joaquin County and communities throughout California.
County leaders emphasized that while the State’s “Clean, Drain, Dry” campaign remains an important prevention tool, areas where the mussel has already taken hold require additional action.
District One Supervisor Mario Gardea said the threat extends far beyond recreation and requires immediate attention from every level of government.
“Golden mussels affect far more than recreational boating,” Gardea said.
“They threaten agriculture and critical local infrastructure, increase flood risks, and could bring major mitigation costs that taxpayers may ultimately bear. Stockton is ground zero for this issue, and we must ask, what invasive species comes next? That is why we need urgent action and strong regional coordination now.”
