Lake Minnetonka boaters will feel new pressure this year to guard against spreading exotic water life following the recent discovery of zebra mussels in Prior Lake -- the first metro-area lake to be infested by the unwanted shell creatures.

Officials plan a 30 percent increase in inspections of boats to look for ride-along aquatic life at public boat launches on Lake Minnetonka.

The Lake Minnetonka Conservation District is expected to approve an extra $21,000 next week to pay for more inspections by the Department of Natural Resources. The DNR will use the money to hire and train more inspectors, expanding hours of inspections from 3,364 last year to 4,672 this year, said Luke Skinner, supervisor of the DNR's invasive species program.

The Conservation District, which manages lake use for the 14 cities ringing the lake, is working with lakeshore property owners represented by the Lake Minnetonka Association to ramp up inspection spending from $44,450 last year to $65,800 this year. The lake association is contributing $10,000 of the additional $21,000 that will go toward heightened enforcement.

Earlier this spring, the association called for emergency boat-launch rules to prevent the spread of zebra mussels into the lake.

The conservation district did not adopt emergency rules, but Dick Osgood, executive director of the lake association, said the association is grateful for the stepped-up inspections.

"We know we can never get 100 percent coverage with inspections, but this is a significant step forward," he said.

Cleaning boats is crucial

The lake association also wants to train some of its members to fill in as volunteer inspectors when DNR staff members are not working. And it is making a plea to boaters to follow good boat-cleaning practices, Osgood said. "This is a serious matter, and everyone needs to pitch in."

Zebra mussels litter beaches, smother native mussels, clog water intakes, and undermine fish and wildlife habitats.

To combat their spread, the DNR recommends that boaters remove all visible aquatic plants, animals and mud from boats, trailers, docks, lifts, rafts and other equipment including anchors, and drain all water from live wells, bilges and bait buckets before pulling away from a lake.

It advises owners to wash their boats with high-pressure sprayers using hot water and then dry them thoroughly inside and out before transporting them to another lake.

During targeted times, the DNR also will patrol roads and ticket boaters moving watercraft with plants hanging from them, Skinner said.

In related action, the Three Rivers Park District Board will hear a proposal Thursday to ramp up its parks' efforts to prevent the spread of exotic species.

As in past years, the park district will inspect boats at entrances to parks at Lake Independence, Medicine Lake and Lake Minnetonka.

This year, the district also plans to distribute more educational materials to people who buy boat-trailer parking permits, said John Barten, director of natural resources for Three Rivers.

The district also is considering putting out bottles of spray bleach at boat launches and offering a cell phone number for a recorded primer on how to clean a boat. The district may also enlist Eagle Scouts to hand out information and talk to boaters at lesser-used launches, Barten said.

Laurie Blake • 612-673-1711