Signaling a get-tough attitude toward a threat to Minnesota lakes, Wright County has become the first county in the state to require boats, trailers, docks and other equipment to be inspected for aquatic invasive species (AIS).

The mandatory inspections apply to only four lakes in the county, but they may signal the beginning of an era when Minnesota boaters can expect greater scrutiny of their watercraft hygiene.

While only about 5 percent of the state's lakes are infested with species such as zebra mussels, Eurasian milfoil and starry stonewort, experts say that once the invaders arrive in a lake, they're difficult if not impossible to eradicate. That has state and local officials emphasizing prevention through equipment inspections and decontamination to make sure that boaters don't spread the invaders from lake to lake.

The state Department of Natural Resources (DNR) is keenly interested in Wright County's effort, said Heidi Wolf, supervisor of the agency's Invasive Species Program. The DNR must sign off on an official delegation of authority to the county before the program gets underway, but county officials said they expect that to happen by the end of July.

"We definitely support counties and local governments and tribes being part of the AIS solution," Wolf said Thursday. "I don't think any one agency or group can solve this problem on its own."

Wright County commissioners adopted the regional inspection program last month. Under the proposal, boaters entering the four lakes — East and West Sylvia, John and Pleasant — would first have to visit an inspection and decontamination station in Annandale.

After inspection, a zip tie would be placed on their trailer. Any trailers at the four lakes found without a zip tie would be subject to a citation from county sheriff's officers.

Local lakeshore owners suggested the program last year, after starry stonewort was found in the Sylvia lakes. Only 10 lakes in the state have starry stonewort, a thick algae that turns the water yellow and can clog boat motors.

"We were shocked," said Chris Hector, president of the Greater Lake Sylvia Lake Association. "One of the first things we wanted to do was make sure nobody got starry from us. We had been looking at regional inspection and asking, 'Why aren't we doing this?' "

Wright County's program is being watched nationwide, said Jeff Forester, executive director of Minnesota Lakes and Rivers Advocates.

"This pilot, if successful, would make Minnesota a leader in AIS activities in the nation," Forester said. "With close to 900,000 registered watercraft and 3,000-plus public accesses, it's difficult to cover every access. This is a step toward a solution."

Forester praised the local lake associations for leading the way.

"It's really local action," he said. The program is being funded by local lake associations and a grant from the Initiative Foundation, a nonprofit that promotes economic development in central Minnesota.

Once the program gets underway, inspectors will be at the Annandale station every day 30 minutes before sunrise to 30 minutes after sunset, said Alicia O'Hare, a water resource specialist with the Wright Soil and Water Conservation District.

"The whole point of the program is to remove the inspectors from the [individual] accesses, because that's how it becomes more cost-effective," she said. Still, the annual cost of the program is expected to run into six figures, she said.

The fight against AIS is difficult because boaters are more mobile today, said Christine Husom, a Wright County commissioner.

"The lakes are very important in Minnesota, and I believe that most people don't want to see lakes being basically ruined by aquatic invasives," Husom said. "We love to swim, we love to boat, we love to recreate.

"To keep the lakes free of invasives is a top priority for a lot of people."

John Reinan • 612-673-7402