A boat heavily coated with invasive golden mussels was intercepted Saturday at a Folsom Lake decontamination station, a stop officials say may have kept the damaging species out of one of California’s busiest reservoirs.
The watercraft had pulled into Mello Marine in Folsom for the required cleaning and tagging process before it could be cleared to launch at the lake. As crews examined the vessel, they found groups of golden mussels attached across the bottom of the hull.
“You can see them underneath here. But as you closer examine it, there’s mussels all over the bottom of the boat,” Mello Marine owner Sally Mello told KCRA.
Mello said her staff has handled decontamination for about 6,000 boats since 2025, but this marked the first time they had discovered golden mussels on one of them.
The boat had traveled from the Sacramento-San Joaquin Delta and, according to Mello, its owner had complied with the required watercraft inspection and decontamination rules. After a planned stop at Folsom Lake — a heavily visited recreation destination that attracts more than 2 million people annually — the vessel was expected to continue north to Oregon.
“Imagine, again, if this boat went to Oregon and now just gets put in the Oregon waters and now it’s north of where it is now,” Mello said.
Golden mussels, an inedible invasive species formally known as Limnoperna fortunei, can accumulate pollutants, toxins and harmful bacteria in their tissue. They also fasten themselves to hard surfaces, including pipes, pumps and other infrastructure, creating serious concerns for water systems, agriculture and local ecosystems.
Environmental officials warn that once golden mussels gain a foothold in a lake, river or reservoir, removing them is considered nearly impossible.
“We’re trying to keep it off Folsom Lake. It’s not there yet. If it gets there, it’s going to be a problem,” Mello said.
A golden mussel was found on a boat in Folsom Lake last year, while authorities recently fined a boater $5,000 at Lake Tahoe for tampering with an inspection seal aimed at stopping the spread.
The California Department of Fish and Wildlife has been notified of the boat contamination and is likely to inspect the boat this week. It will be fully decontaminated and quarantined for 30 days before it can return to the waterways.
Download The California Post App, follow us on social, and subscribe to our newsletters