Who pays for invasive species battle? How much?

Requiring every boat in Minnesota to be inspected for invasive species before watercraft are launched into a lake or river would cost about $600 million yearly -- or about half the cost of a new Vikings stadium.

That's because the state would have to place inspectors at 3,800 public and private accesses during the open water season. If boaters alone were required to pay for that, the current $5-per-boat surcharge would have to be increased to $2,300.

Obviously that's not going to happen, but it underscores the scope of the problem.

"Clearly, having inspectors at every access is cost-prohibitive," said Steve Hirsch, director of the Department of Natural Resources division of water and ecological resources.

That is the most expensive of several options to fight the spread of aquatic invasive species in a report given to the Legislature recently by the DNR. The report, done by a consulting firm to estimate costs of various options, was ordered by the Legislature.

The annual costs range from around $8.6 million, which is what the DNR will spend in the coming year, to the $600 million for total boat inspections. And even those eye-popping numbers don't cover prevention efforts for Asian carp.

The Legislature ultimately will decide whether or how to boost efforts to stem the spread of aquatic invasive species, such as zebra mussels -- and who will pay for it. Whatever route is taken, Minnesota's 800,000 boat owners likely will be asked to pay more for their licenses to help pay for the effort.

Rep. Denny McNamara, R-Hastings, chairman of the House Environment, Energy and Natural Resources Policy and Finance Committee, another key committee, said he supports a boat fee increase.

The battle against invasive species simply requires more money, he said. The question is how much?

"First we have to figure out what we want the DNR to do, then we have to figure out funding," said Rep. Jean Wagenius, DFL-Minneapolis.

Fee increase overdue

The current $5 watercraft surcharge -- the main source of funding for invasive species management -- hasn't been raised since 1993. The surcharge is tacked onto a three-year boat registration fee, so the annual cost to boaters is $1.67. And with inflation, that $5 now is worth about $3.11.

"It's a starting point," Wagenius said.

But that may not be enough.

The state doubled invasive species spending to $8.6 million beginning July 1, including $2.7 million from its invasive species account, funded by the surcharge and a $2 non-resident fishing license surcharge. But it also includes $4.5 million in one-time funding from the lottery, and $1.3 million in general fund dollars from taxpayers -- a proportion that has declined in recent years because of the state's budget crisis.

"At current spending, the invasive species account will go into the red," said Luke Skinner, DNR invasive species program supervisor. "That's why we're looking for long-term funding sources."

The DNR says to maintain the $8.6 million spending level, the boat surcharge would have to jump to $33 for boats 17 feet and under, and $43 for larger boats -- assuming continued contributions from the state's general fund.

Meanwhile, the DNR plans to meet with stakeholders -- including lakeshore owners, local governments, watershed districts, boaters, anglers and others -- later this month or in March to discuss options.

"I'm optimistic we can do some things to slow the spread [of invasives]," Hirsch said. "I don't think we'll be able to totally stop the spread, but I think we can do better."

Doug Smith • dsmith@startribune.com