With warm weather in the forecast for the Labour Day long weekend and many people looking for ways to cool off, Public Health officials at Vancouver Coastal Health warn the public that a “Not suitable for swimming” advisory remains in place for Alice Lake near Squamish, due to a bloom of blue-green algae, or cyanobacteria.
Cyanobacteria are microscopic, plant-like organisms that occur naturally in freshwater lakes, ponds and streams; some varieties produce cyanotoxins that harm humans and animals. With conditions that include calm water, high temperatures and an increase in nutrients such as phosphorus, populations of cyanobacteria can rapidly increase to form a large mass or scum called a bloom.
Scientists believe rising temperatures and more intense storms due to climate change are causing an increase in algal blooms.
VCH Public Health issued an advisory for Alice Lake on Aug. 20–it’s the first ever issued in the VCH region because of blue-green algae. Medical Health Officers advise that exposure to toxins produced by cyanobacteria may cause nausea, vomiting, diarrhea or fever in humans or their pets. Those who come in contact with the algae should rinse off with a clean source of uncontaminated water.
Drinking water in Alice Lake Provincial Park is serviced by wells and is unaffected by the algal bloom. Only Alice Lake is closed to swimming and wading, and there is no evidence of similar blooms in other lakes in and near the park; they remain open for recreational activities.
VCH’s Beach Water Quality Program collaborates with partner agencies that manage beaches, conduct sampling, and analyze recreational waters. Throughout the summer, water is sampled at many beaches throughout our region, and results are posted online at www.vch.ca/beach.
