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Blue-green algae advisory issued for Thunder Lake west of Barrhead

People and pets should avoid contact with blue-green algae blooms and should not drink untreated water from the lake
Thunder Lake (VM)
A blue-green algae (cyanobacteria) bloom has been spotted in parts of Thunder Lake, as seen in this file photo. The advisory will remain in effect until Alberta Health Services lifts it.

Alberta Health Services (AHS) has issued a blue-green algae (cyanobacteria) bloom advisory for Thunder Lake in the County of Barrhead. 

Similar advisories were also recently issued for Lac La Nonne on July 15 and Lac Ste. Anne on July 21. Notably, the latter came out just prior to the Papal visit to Lac Ste. Anne. 

Blue-green algae — which is not technically algae at all, but rather a cluster of bacteria that resembles algae — is naturally occurring and often becomes visible when weather conditions are calm.  

Blue-green algae can resemble scum, grass clippings, fuzz or globs floating on the surface of the water and often smells musty or grassy. Despite the name, the algae can be greenish-brown, brown, or pinkish-red in colour.  

People who come into direct contact with blue-green algae or who ingest water containing the bacteria may experience skin irritation, rashes, a sore throat, swollen lips, sore red eyes, fever, nausea, vomiting and/or diarrhea.  

Symptoms usually appear within one to three hours and may take one or two days to resolve. The symptoms may be more pronounced in children and especially animals, who may require veterinary attention. 

Residents living near the shores of Thunder Lake, as well as visitors to the lake, are advised to avoid all contact with blue-green algae blooms. If contact occurs, wash with tap water as soon as possible. 

People should not swim or wade in any areas where blue-green algae is visible and should not allow their animals to do the same. (Areas where the bloom is NOT visible can still be used for recreational purposes.) 

As fish can store toxins from cyanobacteria in their liver, visitors should not feed whole fish or fish trimmings from Thunder Lake to their pets, while human consumption of fish and fish trimmings from the lake should be limited. Consumption of fish fillets by humans is safe. 

As always, people should never drink or cook with untreated water from any recreational body of water, including Thunder Lake. Boiling of this water will not remove the presence of toxins produced by blue-green algae. 

An alternate source of drinking water should also be provided for pets and livestock while this advisory is active. 

Because weather and wind conditions can move algae blooms from one part of the lake to another, this advisory will remain in effect until further notice. 

If you suspect a problem is related to blue-green algae or you just need more information about health concerns, you can either visit or call Health Link at 8-1-1.

Kevin Berger,

About the Author: Kevin Berger

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