Parks Canada installs almost 2-km curtain to contain zebra mussels in Clear Lake

A silt curtain is being installed and will soon be fully deployed to try to contain the spread of zebra mussels in Clear Lake, in Riding Mountain National Park.

Once installation is complete, the curtain will run just under two kilometres from the west side of Boat Cove to Clear Lake's main beach in Wasagaming, said Dameon Wall, Parks Canada's external relations manager at Riding Mountain. The impermeable curtain will try to contain an area wherea zebra mussel and partial shells were found in mid-July by Parks Canada snorkellers.

"This is one of the longest deployments that we're aware of anywhere," Wall said. "It is quite an operation to get all that material on site and then put together and then take out into the lake."

The first section of the curtain was installed on Monday and installation is slated to be completed Wednesday. It is a heavy waterproof membrane that will naturally fall to the bottom of the lake where it is then secured with weights and a chain.

Since the adult zebra mussel was found, scientists have sent 78 water samples to the Department of Fisheries and Oceans from different parts of the lake. The results of the most recent tests were unavailable, Wall said, but Boat Cove water samples have seen consistent zebra mussel DNA results since testing began after scientistsfound live zebra mussels in the lake in November.

Right now there's no information on how long the curtain will be in place. Wall said it needs to be ready in the event that Parks Canada proceeds with a potential eradication attempt of the invasive species with a liquid potash treatment a decision that has yet to be made.

WATCH | Aerial drone view of Clear Lake curtain:

Aerial view shows curtain intended to halt spread of zebra mussels in Clear Lake

1 month ago

Duration 1:40

Video supplied by Parks Canada shows the extent of the impermeable curtain intended to prevent the spread of zebra mussels in western Manitoba's Clear Lake. It will run just under two kilometres from the west side of Riding Mountain National Park's Boat Cove to Clear Lake's main beach.

Clear Lake wasalso closed to most outside watercraft including canoes, kayaks and paddleboards this season to prevent the spread of the invasive species.

Parks Canada also paused operations for Clear Lake's Martese a tourist vessel initially exempt from the boat ban onWednesday. Wallsaid that's because a positive zebra mussel environmental DNA sample was found near the marina the Martese operates out of.

There is no impact on swimming, fishing, or access to the beach at this time, Wall said. The recent measures are part of Parks stepping up their response to the invasive species because they only have this summer to try and eradicate the mussels.

"There is urgency in this battle against zebra mussels because once they become established there is no known way currently to get rid of them," he said.

"If they become established in Clear Lake they will move out of the lake and it will have an impact on agriculture, on industrial, on the drinking water supply for tens of thousands of Manitobans, on five First Nations as well."

Community concerned

When Matt Gould and his family arrived in Wasagaming this week, the first thing they noticed was the usual boats cruising on the water were missing. In their place was a long yellow curtain floating on the lake.

They also talked to some conservation officers about the curtain and how Parks Canadawas attempting to stop the spread of zebra mussels from one part of the lake to the other.

"The entire project has been somewhat extreme, but in a good way. They've taken it seriously," Gould said.

Randy Loewen often visits Clear Lake but also has a summer place on Lake Winnipeg, where zebra mussels have become established. Loewen says shoes are essential at Lake Winnipeg because there are thousands of dead mussels on the shores that are sharp and can cut feet.

He worries that could be Clear Lake's future.

"I hope it works ... butthis is a big lake and if they're here, they're here.I don't know what they're going to do," Loewen said. "I don't think they're going to get rid of them."

When Marcel Barreto and his family booked their usual camping site this year, they received a warningthat watercraft would not be allowed on the lake as part of the efforts to stop the spread of zebra mussels.

It was disappointing to learn they couldn't kayak this summer, Baretto said, especially because he doesn't think the curtain or boat ban will work to contain the invasive species.

"I hope that next year they're going to stop doing all those things and just let the people use their kayaks at least."