The Ministry of the Environment, Conservation, and Parks has found blue-green algae in Marie Louise Lake in Sleeping Giant Provincial Park.
The algae was found in water samples taken on September 21.
Marie Louise Lake is located roughly 85 kilometres east of Thunder Bay, off Highway 587.
BGA are microscopic organisms that are naturally present in lakes and streams.
They are usually present in low numbers but can rapidly increase in warm, and shallow water that gets a lot of sun.
Some blooms produce toxins that pose a health risk to people and animals when consumed, inhaled, or even from skin contact.
Water in the lake should be avoided and you and your pets should not drink it, swim in it, or use it for household purposes.
If contact with a BGA bloom does occur, wash with soap and water and rinse with clean water to remove the algae.
Historically, BGA blooms in the region have been relatively uncommon.
The Ministry says warmer weather and rising water temperatures may lead to more algae blooms.
