GREENSTONE — A blue-green algae bloom has been reported on a lake near Greenstone.
On Monday, the Thunder Bay District Health Unit confirmed a cyanobacteria bloom at Kenogamisis Lake, located at the southwest arm of the lake.
The health unit’s notice on Monday advised people to avoid drinking the water, swimming in it or using it for any household purpose. Not only should those precautions be taken while the bloom is present, but also for about two weeks after it visibly disappears.
Domesticated household pets should also be kept away from the water, with the health unit’s advisory saying “their smaller size and habit for drinking lake water makes them vulnerable.”
Cyanobacteria blooms in lakes in region "have been relatively uncommon, historically," the health unit's advisory said. "However, with changing climate and rising water temperatures they may become more common."
This is the second blue-green algae bloom reported by the Thunder Bay District Health Unit in 2025, following one at Hattie Cove in Pukaskwa National Park earlier in August.