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Warning: Blue-Green Algae in Alberta Lakes

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Blooms of blue-green algae have been spotted in lakes across Alberta. Blue-green algae can look like scum, fuzz, or globs on the water’s surface and can appear blue-green, greenish brown, brown, or pinkish red in colour with a musty or grassy smell.

Bodies of water that contain blue-green algae are to be avoided by you and your animals at all times. Do not swim or wade in contaminated water, and if contact is made by you or your animal wash the affected area immediately. Whole fish or fish trimmings from contaminated bodies of water should not be ingested by people or animals, though fillets should be safe for consumption. It is also imperative that water contaminated with blue-green algae is not used to cook, drink, or water vegetable gardens. Boiling this water will not sterilize it.

If you suspect your animals’ water may be contaminated, find them an alternate water source and remove their access to the contaminated water immediately. If you use a dugout to supply water, it is best to inspect it at regular intervals over the warmer months. Among other things you can do to improve your dugout, building a deeper dugout with steeper walls will help to keep it cool and free from blue-green algae.

The symptoms listed below often appear within a few hours of contact and are usually resolved within a couple of days. Visible symptoms are much more prominent in children. If you notice any combination of these symptoms in a person or animal, contact their physician or veterinarian immediately:

  • skin irritation
  • rash
  • sore throat
  • sore, red eyes
  • swollen lips
  • hay fever symptoms
  • fever
  • nausea
  • vomiting
  • diarrhea

The disappearance of blue-green algae does not indicate that the water is safe. The harmful toxins can remain in the water for several weeks after the algae blooms have disappeared. For more information on affected areas and the status of particular lakes, please visit Alberta Health Services.


PDF icon AHS Blue-Green Algae FAQ 2020954.04 KB