Water advisories issued for Slave Lake, Alberta Beach

Lesser Slave Lake Provincial Park in northern Alberta. July 14, 2025. (Alberta Parks)

Alberta Health Services (AHS) has issued water advisories for two lakes ahead of the long weekend.

Visitors to Lesser Slave Lake in north-central Alberta are advised to keep an eye out for blue-green algae.

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Exposure to blue-green algae can cause skin irritation, rash, sore throat, sore red eyes, swollen lips, fever, nausea, vomiting and diarrhea. Blue-green algae can be fatal to pets.

AHS recommends washing with tap water as soon as exposure occurs.

Humans are also advised to limit consumption of whole fish and fish trimmings from the lake. Feeding whole fish or fish trimmings to pets can result in death. Fish filets from the lake are still safe for human consumption.

Blue-green algae, also known as cyanobacteria, appears on the water’s surface and can often look like scum, grass clippings, fuzz or globs. It can be blue-green, greenish-brown, brown or pinkish-red and often smells musty or grassy.

Waters of Lesser Slave Lake where algae blooms are not visible can still be used for recreational purposes even while the advisory is in place.

Lesser Slave Lake is about 200 kilometres north of Edmonton.

Alberta Beach is also under an advisory but for elevated levels of fecal bacteria in the water of the main beach area.

AHS is advising the public not to swim or wade at the beach area, effective immediately.

At current levels, gastrointestinal illness may result from ingestion of the water at Alberta Beach, said the health authority, adding there is also a possibility of contracting skin, ear and eye infections with water contact.

The advisory will remain in effect until further notice while AHS Environmental Public Health officers continue to monitor the water at Alberta Beach.

Alberta Beach is located about 70 kilometres west of Edmonton.