No further sign of zebra mussels in Assiniboine River

There has been no further evidence of zebra mussels in the Assiniboine River since larvae were found late last year, with additional testing returning negative results.

The province announced in December that dead zebra mussel larvae were found in the river at the Brandon Generating Station (BGS).

Signage at the Assiniboine and Little Saskatchewan rivers has since been posted advising boaters to decontaminate their equipment, the province said in an email.

“The province is still determining the scope and extent of the detection and cannot know next steps until this information is known,” the email said.

Manitoba Hydro said BGS’s operations haven’t been affected.

The province said the negative samples are “common during an early part of an invasion and in the earlier part of the open-water season.”

No positive results have come from testing in other bodies of water in the area.

Brandon Mayor Jeff Fawcett said the city is doing what it can to work with the province to reduce the risk of aquatic invasive species.

“We work alongside the province, get them information as they need, receive information from them and generally just operate alongside them,” the mayor said.

He said the province is looking at setting up a containment plan, but added he doesn’t know exactly what areas it would include.

“My understanding is this is not inside the City of Brandon, but along it,” he said, noting that could change.

Fawcett said Brandon being downstream from Riding Mountain National Park — where motorboats are now banned because of the prevalence of the species — is a concern, as are other factors related to the river, like flooding.

“I think there’s a number of places in Manitoba that have a lot of aquatic species in them, but not necessarily connected to our river,” he said. “They’re keeping an eye on all of it.”

Brandon Riverbank is reminding people to make sure to clean their boats, kayaks and other equipment.

“While Brandon Riverbank is happy to once again see paddlers on the Assiniboine, we all need to be aware of and do our part to help stop the spread of Aquatic Invasive Species,” the group posted on Facebook Thursday.

Manitoba Hydro, which found the evidence of mussels last year, said it’s important that it heightens testing at BGS.

“We are increasing monitoring to get a better understanding of what level of infestation the facility could be facing,” media relations officer Peter Chura said in a statement.

He said the Crown corporation monitors zebra mussels because they can become a nuisance to its infrastructure.

“Zebra mussels become a problem for our facilities when they settle inside pipes, clog cool water systems, and interfere with normal operations,” he wrote. “We monitor inside all our facilities that have confirmed zebra mussels, and we monitor lakes and rivers where we operate that have yet to be infested by zebra mussels.”

He said once there is a certain level of zebra mussels in a facility, a “very small dose of chlorine” is injected to kill them.

While the process isn’t happening in Brandon, he said it’s happening at several facilities in northern Manitoba.

One facility west of Gillam, the Keeyask Generating Station, will be using potash to kill the mussels, something that Hydro hasn’t done before.

» alambert@brandonsun.com