Alberta Health Services (AHS) has issued a blue-green algae advisory for the Sherburne Reservoir near Taber.
The public is advised to avoid all contact with algae blooms in the water until further notice.
AHS said boiling the water will not remove toxins produced by blue-green algae and recommends finding an alternate source of drinking water for pets or livestock while the advisory is in place.
Blue-green algae is naturally occurring and often becomes visible when weather conditions are calm, according to AHS, but wind conditions can cause algae blooms to move from one location to another within the reservoir.
People who come into contact with it may experience skin irritation, rash, sore throat, sore red eyes, swollen lips, fever, nausea and vomiting and/or diarrhea.
The Sherburne reservoir is located about 38 kilometres southeast of Taber.