The power washer hummed as a jet of hot water hit the back of the boat.
Its target: unwelcome visitors to the state of Idaho, namely zebra mussels. These tiny creatures, not native to Idaho, could cause big problems if they get a foothold in the state’s waters.
For the first time this year, a boat contaminated with the mussels was stopped at an inspection station on U.S. Highway 93 in southern Twin Falls County north of the Nevada state line, said Staff Sgt. Matthew Eden with the county sheriff’s office. The 20-foot pontoon boat was impounded by deputies and brought to a parking lot at the rear of the county courthouse. The Idaho State Department of Agriculture was alerted and its contractor, Power Wash Plus of Boise, responded to clean the boat.
The mussels, along with other creatures and plants, are on the state’s invasive species most-wanted list. They can threaten fisheries, waterways, recreation and agriculture in Idaho if they invade and spread, according to ISDA.
This is the second year of the inspection program, which is partly funded by fees from a $10 sticker that boat owners are required to purchase. All boats are also required to stop for inspection at sites overseen by ISDA.
“The purpose of the inspection is to catch the ones that are coming in,” Eden said.
The boat, owned by a Donnelly resident, was heading to Cascade from Lake Havasu, Nev., said Chuck Dearman, president of Power Wash Plus. The mussels, mostly younger ones that had not yet developed shells, were found on the anchor and elsewhere under the boat.
In addition to using water heated to 140 degrees to remove the mussels, Dearman’s company also tested the use of small pellets of dry ice. When the pellets are blasted out by compressed air, they strike the surface and blow off the offenders, but don’t damage the boat, Dearman said. When the pellets return to gas form, that process blows apart the shells of the zebra mussels.
The cleanup took about an hour and half at no cost to the boat owners.
This was the first zebra-mussel cleanup in southern Idaho by Dearman’s company and the first use of the dry ice. He said he was pleased with the results.
The inspection program snagged just two confirmed mussel-infested boats last year. Out of 18,450 total boat inspections, there was one confirmed case of quagga mussels (another invasive species), one confirmed case of zebra mussels and one unconfirmed report of a boat infested with one of the two. All three cases were at stations in north Idaho, according to figures obtained from ISDA last fall.