The Lake Minnetonka Association is calling for emergency boat launch rules for the coming season to prevent the spread of zebra mussels into the lake.

An exploding population of zebra mussels in Lake Mille Lacs warrants emergency action to protect Lake Minnetonka, the association says. It wants to require that all boats be clean and dry, inside and out, before they enter the lake.

The lakeshore owners group is pushing the Lake Minnetonka Conservation District, which manages lake issues for the 14 cities ringing the lake, to adopt these ramp rules and step up efforts to protect the lake from invasive species. It is also asking the cities to work on the problem as well.

"The Lake Minnetonka Association believes it's the state's job to put a lid on aquatic invasive species and zebra mussels statewide,'' said Dick Osgood, executive director of the association. "But it's the local job and responsibility to protect local lakes like Lake Minnetonka.''

Shorewood Mayor Christine Lizee said she will invite the mayors from all 14 lake communities to a meeting on April 15 to discuss the issue.

"It's the one thing that ties us all together and our big claim to fame,'' Lizee said of the lake. "What we want to do here is show some leadership in how to manage a lake and how to protect it from these things that are coming from all over the country."

She warned, "This is the most heavily used lake in the state. If something goes bad here, it's going to be bad everywhere.''

The zebra mussel is a non-native, fast-spreading creature that can disrupt aquatic food chains, smother native mussels, clog water intakes and foul beaches. Transporting them is against Minnesota law.

The Lake Minnetonka Association estimates that 1,000 to 2,000 boats a year come to Lake Minnetonka from Mille Lac and other waters infested with zebra mussels, so it wants a more serious approach to protecting the lake against all invasive species. It has offered to pay 25 percent of the cost of a stepped-up control program. It has called for boat launch fees or higher conservation district taxes to pay for the rest of the cost.

Conservation District chair Lisa Whalen said zebra mussels were discovered in Minnesota in the mid-1990s and have been a threat to Lake Minnetonka ever since. The conservation district has spent hundreds of thousands of dollars on education campaigns and inspections, she said.

"Yes, zebra mussels are in Mille Lacs,'' Whalen said. "Everybody's awareness needs to be heightened, and they need to thoroughly inspect their boats and everything they put into the water.''

But, she added, "Why they are all of a sudden saying this is an emergency I am not sure, because [zebra mussels] have been an emergency since they were discovered.''

This year the district received about $330,649 from the 14 supporting cities. Of that amount, $65,000 will go to district plans to spend $139,000 for aquatic weed-harvesting and boat inspections to combat invasive species, executive director Greg Nybeck said. The remaining money from the cities goes into the district's administrative budget.

The district's exotic species committee will consider the association's proposal, Whalen said. But she said she doubts the district has the authority to enforce ramp rules.

The Department of Natural Resources does have the authority to inspect boats at ramps and ticket boat owners carrying vegetation. Luke Skinner, supervisor of the department's invasive species program, said DNR inspectors will do less educating and more ticket-writing this summer.

Skinner said "I think the risk has increased'' on Lake Minnetonka because the population of zebra mussels in Mille Lacs "is starting to really take off.''

But, Skinner said, "I still think the greatest risk to Lake Minnetonka is coming from the Mississippi and St. Croix Rivers,'' both of which are infested by zebra mussels.

Big boats from the rivers often are moored there for months, giving zebra mussels time to attach, before they are moved to Lake Minnetonka for a change of scenery, Skinner said. Boats coming from Mille Lacs tend to be day users, Skinner said.

Last year, 99 of the 13,573 boats the DNR inspected on Lake Minnetonka came from Mille Lacs, 69 came from the Mississippi River and 80 from the St. Croix, Skinner said. "But no boats were found with zebra mussels.''

Tickets for transporting aquatic vegetation, carrying zebra mussels and launching a boat-carrying invasive species carry fines of $50 to $500, Skinner said.

DNR inspections are targeted during high-use evening and weekend times. The association recommends more.

Laurie Blake • 612-673-1711