Parks Canada is taking swift action to stop the spread of invasive mussels in the pristine water of Waterton Lake.

Effective immediatly all motorized boats, and boats hauled by trailers, will no longer be allowed in the lake.

Larva of the mussels has been discovered in the Tiber Reservoir in Montana, 49 kilometres away.

"We had to act very quickly," said Foothills MP John Barlow.

The ban was put in place Thursday afternoon, March 16th.

Parks Canada, with Environment Canada, were in full support of putting the ban in place.

The tourist boats that only go in the lake are allowed to stay, and canoes and kayaks, as long as they are not brought in on a trailer will be allowed.

"The tourist boats like the International is still okay because it doesn't leave that water, you can still canoe and kayak,"

"It's a hard decision, but it is the right decision. It is the headwaters for the south Saskatchewan river basin, it is pristine."

It has very unique fish habitat and plant life.

"If the zebra mussel were to get into that lake there is no known technology or pesticide to remove it. It takes over and would destroy the habitat."

Last year 500 permits were issued for motorized boats in the lake, which isn't a huge number when you consider the park had almost half-a-million visitors last year.

"We have to protect that water body. It is a gem for Alberta for sure and an important watershed and one of our precious national parks.  

The prohibition is likely to be permanent.

Barlow explained the mussels very quickly take over the water body, changing the chemistry it and clogging up dams, drain pipes and destroying the plant life.

He added In the United States they spend a billion dollars a year trying control problem in their water and if If gets into Alberta lakes it could cost 100 million dollars a year.

Barlow will be asking Environment Canada what other plans are in place to keep the Zebra Mussels out of Alberta.

"With tens of thousands of people crossing the borders, it could be impossible to get every boat that has the species hiding on it," Barlow said.

"People who are boating enthusiasts do their very best to make sure their boats and trailers are clean, but it can be impossible to get everything so the only option is to put a restriction on boating."