An invasive species of mussels first discovered in the Port of Stockton is now getting attention in Washington, D.C.
Rep. Josh Harder, D-Tracy, said this week he has joined other Delta-area members of Congress in introducing a bill aimed at trying to halt the spread of golden mussels. The mollusks have been found in various parts of the Delta and as far south as Bakersfield.
The discoveries have prompted a variety of measures, including closure of at least one popular San Joaquin County reservoir to the launching of boats, kayaks and other watercraft.
Perhaps most alarming, officials at Lake Tahoe say their inspectors found a boat that the owner had hoped to launch that was encrusted with golden mussels. They say the mussels pose an “extreme threat” to the pristine lake.
“Don’t let the name fool you. These golden mussels are sharp, slimy and stinking invaders that clog our waterways with sludge and threaten our fragile Delta ecosystems. We need to act now to stop their advance,” Harder said in a statement.
Harder said the bill that was introduced will protect Delta and waterways by initiating a rapid response program to contain and eradicate infestations. It also will fund new technology and inspection stations and foster coordination between local, state and federal agencies.
“This bill protects our waterways and our Delta economy by jumpstarting eradication efforts right now, not when it’s far too late,” he said.
Golden mussels can grow fast and clog drains, pipes and other water systems, causing thousands of dollars in damage. They are native to Asia, and most likely found their way to Delta by hitching a ride on the bottom of a ship, experts say.
After being discovered in Stockton in October, California’s Fish and Game Commission took emergency action. The agency made it illegal to possess, transport or import live golden mussels.
Some recreation areas have even taken their own action. At Camanche Reservoir, about 35 miles northeast of Stockton, the East Bay Municipal Utility District has closed the boat launch for the entire 2025 season.
Lake Tahoe authorities stepped up a boat inspection program starting in March. There’s also a mandatory inspection process that all power boats must follow before launching into Lake Tahoe, Fallen Leaf Lake and Echo Lake.
As proof of the importance of the program, golden mussels were found on a 46-foot boat that had been brought for launching at Lake Tahoe. It was being held for decontamination until it can be determined that the vessel is risk-free.
“With the support of boaters and paddlers, we have kept Lake Tahoe safe from many invasive species, but the survivability of golden mussel and their proximity to Tahoe make them a greater threat than other aquatic invasive species,” Chris Killian, the aquatic invasive species program manager for the Tahoe Regional Conservation District, said in a statement.