Blue-green algae warning issued for Lac Ste. Anne

Alberta health officials have issued a blue-green algae advisory at Pigeon Lake. Algae blooms can be seen in parts of the water and on the shore on July 18, 2025. (Nav Sangha/CTV News Edmonton)

Blue-green algae has been found in Lac Ste. Anne, Alberta Health Services (AHS) is warning the public.

AHS said water that does not contain algae blooms can still be used recreationally while the advisory is in place, but advised lake users to avoid contacting or ingesting water where blooms are visible.

That includes eating fish or fish trimmings from the lake, and keeping pets away from infected areas.

Blue-green algae, known scientifically as cyanobacterial bloom, occurs naturally, often in warm weather.

Blooms look like scum, streaks, grass clippings, fuzz balls, paint, or pea soup and can be a variety of colours and smell musty or grassy.

People who come in contact with blue-green algae are at risk of experiencing skin irritation, rash, sore throat, red eyes, swollen lips, fever, nausea, vomiting and/or diarrhea.

Exposure to pets can be fatal.