Minnesotans flocking to the state's lakes and rivers this weekend for the start of another boating season will be greeted by more inspections and citations across the state.

Thanks to an unprecedented $10 million from the state, counties are ramping up work to stop the spread of aquatic invasive species like zebra mussels. That means more inspectors will be stopping boaters this busy Memorial Day weekend to check for signs of the pests. More educational efforts will start up. And conservation officers will be stricter about state laws, doling out fewer warnings and more tickets for contaminated boats.

"We need to get that behavior change," said Greg Salo of the Department of Natural Resources' enforcement division. "This year, we're going to be more aggressive."

Over the last few years, inspections and regulations have become the new norm for Minnesota's 800,000 registered boaters, despite critics who are skeptical that inspections are worthwhile and others who want unfettered access to public waterways. Now, this year, measures are intensifying locally.

"Now we have a broader blanket across the state," said Ann Pierce of the DNR's ecological and water resources division. "[Boaters are] going to see more people out there. This is to make sure everybody understands the role they play in preventing the spread."

On Christmas Lake, where more zebra mussels were discovered last week, the west metro homeowners want to take it a step further, not just relying on inspections but decontaminating every single boat entering and leaving the lake. Other cities can't afford to do that, but instead are shifting to better educate residents and enlist the help of volunteers. From Detroit Lakes to Lake Minnetonka, programs are recruiting residents to monitor water for the first signs of an unwanted species.

"People are starting to understand the gravity of the problem," said Barb Halbakken Fischburg of the Lake Detroiters Lake Association, which has 60 residents installing zebra mussel monitoring samplers in June. "Everybody has to be part of the solution."

More than 500 Minnesota rivers, lakes and wetlands are designated as infested with aquatic invasive species. Of those, more than 200 waterways are listed as infested with zebra mussels, which clarify water but also clog motors, alter the ecosystem and pose a hazard to swimmers due to razor-sharp shells. Still, many of Minnesota's more than 10,000 lakes aren't infested.

"We want to keep it that way," Salo said.

Fewer warnings, more fines

Changing the quality of waterways and fishing could put a dent in the state's $11 billion-a-year tourism industry, which relies heavily on resorts and water recreation.

As zebra mussels began to spread to the state's lakes, unprecedented regulation resulted. In 2010, a state law change required boaters to remove the drain plug before transporting a boat — the No. 1 violation the DNR still sees. Boaters must also clean off weeds and drain water from bait buckets and livewells before transporting it, or risk a $100 to $150 fine. Transporting zebra mussels results in the biggest hit: a $500 fine.

"It's really simple — just pull your plug and clean your boat; it takes less than five minutes to do that," Salo said. "It only takes one boat" to infect a lake.

For the holiday weekend, one of the busiest boating weekends of the year, the state's 148 conservation officers will be out in full force — and ticketing. Salo said the violation rate is stagnant, with 17 percent of boaters stopped at checkpoints disobeying rules.

"The first few years we tried to focus on education; it's kind of a culture change for people," Salo said. "But we've gotten to the point now, to get the rest of the public to change, we have to take a stronger approach."

While the 150 DNR inspectors checking and decontaminating boats statewide hasn't changed, local groups are expanding their programs, such as those at Forest Lake and the St. Croix River, where groups on both sides of the state border are boosting the number of inspectors.

Police also will step up enforcement of speeding and drunken boaters. On Lake Minnetonka, one of the busiest lakes in the state, the conservation district is spending $33,000 to have a dedicated deputy patrol during peak boating hours, prompted by unruly, speeding boaters who caused damage and safety concerns last year. The Hennepin County Sheriff's Office Water Patrol — which covers 107 lakes and rivers — also has a new satellite station at the lower part of the 14,000-acre lake.

Boaters will also see low water levels after record high levels last year. But recent rain has helped many lakes rebound after the dry winter and spring, and the DNR says most access points are usable.

New efforts this year

Besides boosting education and enforcement, some groups are going on the offensive.

Last week, crews on Lake Independence in Maple Plain applied potassium chloride, or potash, to kill off zebra mussels that have infested the lake — only the second time in Minnesota it's been used on a lake. The first one, Christmas Lake, successfully killed off mussels in an isolated area with potash and a biological pesticide thanks to crews closely monitoring the lake.

In Forest Lake, the local watershed district is spending nearly $40,000 trying to treat eastern flowering rush — the only lake in Minnesota with that variant of the species. And in Chanhassen, 10 Lake Minnewashta residents are voluntarily tying devices to their docks to help check for zebra mussels.

"If we're quick enough, like Christmas Lake, we might be able to contain them," said Steve Gunther, who heads the lake homeowners association.

The monitoring devices, four plastic shelves attached to a rope, are part of the Minnehaha Creek Watershed District's new program that has three dozen volunteers installing devices in five lakes. That close monitoring proved worthwhile at Christmas Lake, where 10 mussels were found last week and quickly removed. The homeowners association, one of the most aggressive in the state, is now seeking DNR approval to decontaminate every boat at the Shorewood access, whether or not there's a sign of invasive species.

"If the people who care don't step up to protect the lake, the government won't do it on their own; there's too many lakes," said Joe Schneider, who heads the group. "It's trying to do everything we can."

Kelly Smith • 612-673-4141