Manitoba plans to dump potash into Lake Winnipeg to eradicate zebra mussels

zebra mussels

Aggressive zebra mussels continue to make a home for themselves in Lake Winnipeg, but this year, Manitoba officials have devised a bold plan to help stop their invasion. 

As the ice recedes on Lake Winnipeg, scientists want to experiment with lowering a silk curtain onto the lake floor, in an effort to seal off four harbours infected with the mussels. A high concentration of liquid potash, which clogs the mussels gills, will then be pumped into the water.

Why is it so important to get rid of them?

“Where zebra mussels have established, they have a significant ecological and economic impact,” Lauren Janusz, a fisheries biologist with Manitoba Conservation, said in an interview with The Canadian Press. “There are annual maintenance costs to having zebra mussels that just never go away.”

These tiny clam-like creatures are also capable of spreading incredibly quickly; in fact a female can produce up to one million eggs per year. Once the larvae hatch, the mussels will attach to a variety of hard surfaces, including crayfish, other species of mussels, and boats. 

According to reports, the Manitoba government was presented with a variety of options and chose to try dumping liquid potash into the lake because it isn’t harmful to other aquatic species, apart from native mussels.

There are concerns, however, that the procedure will not be successful. The experiment was previously conducted on a closed quarry in Virginia, so this is the first time it’s being used on a large freshwater lake. 

While the plan is estimated to cost half a million dollars, if it’s successful, it could save the government millions in the future.

“There is only one guarantee and that is, if nothing is done, then the situation will certainly get worse,” Manitoba conservation minister Gord Mackintosh told The Canadian Press. “The impact of zebra mussels in areas where they have infested waterways is quite profound.”

But during this attempted eradication, the people who depend on the lake could be greatly affected. According to the CBC, the four harbours (Gimli, Winnipeg Beach, Balsam Bay, and Arnes) will be forced to close in order to dump the potash into the harbour. Mackintosh said the process could take a month, which would be from mid-May to mid-June, therefore impacting those who rely on the region’s tourism and fishing industries as their livelihood. 

Regardless, it’s still considered a priority for many. “Given that this animal is in the early stages of its invasion in Manitoba,” said Hugh MacIsaac, Director of Canadian Aquatic Invasive Species Network, “I think it’s important to try to eradicate it.”