The province will start to treat four Lake Winnipeg harbours with liquid potash to eradicate zebra mussels next week.
Winnipeg Beach harbour will be treated first.
Crews will install gated silt curtains and then pour the liquid potash into the water.
Officials estimate the treatment should be complete by early June.
Harbours at Arnes and Grand Marais will be outfitted with the silt curtains later this month.
Gimli and Boundary Creek are the other two harbours to be treated with the potassium-based solution.
The province estimates the potash treatment at those harbours should be complete before mid-June.
Fishing boats and most recreational boat traffic will not be restricted during the treatment.