CPW boat inspectors say mussel-infested watercraft becoming more common

Mussels cling to the bottom of boats and have caused billions of dollars in damage.

So far, Colorado’s reservoirs have avoided the mussel infestations that plague the Lower Colorado River in nearby states and the upper Midwest.

Colorado Parks and Wildlife would like it to stay that way. But it’s proving a challenge this season as Colorado’s boat inspectors are inundated by an unprecedented number of infected boats.

“I am just being completely over-run by mussel infested boats,” said Robert Walters, CPW’s assistant manager for the aquatic nuisance species program. “We are already up to 51 interceptions this year. We are having interceptions just about every day at waters throughout the state. And most of the boats are coming out of Lake Powell.”

Lake Powell — a popular recreation site that straddles the border of Utah and Arizona — is particularly problematic, CPW reports. All water vessels are meant to be inspected when they leave the compound, but inspections stations are overwhelmed and not all boats are inspected thoroughly. Inspectors have even found mussels clinging to canoes and paddleboards.

Any boats with a mussel problem must go through a decontamination process, which can take upwards of a week. All boats that have not been “sealed” by boat inspectors at a Colorado reservoir go through a thorough inspection and engine flush at inspection stations.

Instances of mussel infestations are increasing. In 2018, 51 boats with adult mussels were found at inspection stations, nearly twice the record of 26 boats in one year. Since the ANS program started in Colorado in 2008, nearly 4.5 million boats have been inspected, more than 90,000 boats have been subject to some type of decontamination procedure, and more than 200 vessels with confirmed infestations have been intercepted and decontaminated.

Colorado’s reservoirs are still mussel-free, but any introduction of the species would be devastating. Because mussels eat plankton, they would compete with indigenous fish and disrupt the whole food chain in reservoir ecosystems. They also clog aquatic infrastructure like dams, irrigation systems, and boat engines.

CPW warns boat owners that have been in Lake Powell to be extra careful and inspect every inch of their watercraft and trailer.

If you’re a boat owner you can contact CPW for more information here.