The City of Edmonton says the area of Hawrelak Park Lake in which the ITU World Triathlon is scheduled to take place this weekend is safe for the swimming event.
The news comes nearly three weeks after Alberta Health Services issued a blue-green algae (cyanobacteria) bloom advisory for the lake in Edmonton’s river valley.
Recent testing shows that although blue-green algae is still present in the lake water, the concentration of cells has been reduced to such an extent that it doesn’t pose a health risk to the athletes who will swim in the lake.
After the bloom advisory was issued, the city chlorinated the water — the same process used to rid the lake of the algae in 2015, just days before last year’s ITU World Triathlon.
Treatments and testing will continue through the weekend to ensure water safety is maintained for all athletes.
The city cautioned that while the water has been approved for use for the Triathlon, the blue-green algae advisory remains in effect for all areas of the lake in which the algae bloom is visible.
Blue-green algae is naturally occurring and often become visible when weather conditions are calm. Appearing like scum, grass clippings, fuzz or globs on the surface of water, the bacteria can be blue-green, greenish-brown, brown, and/or pinkish-red and often smells musty or grassy.
AHS says people should not drink or cook with untreated water directly from any lake, including Hawrelak Park Lake, at any time. While the advisory is active, pets should not drink from the lake either.
People who come in contact with visible blue-green algae may experience skin irritation, rash, sore throat, sore red eyes, swollen lips, fever, nausea and vomiting and/or diarrhea. AHS said symptoms usually appear within one to three hours and resolve in one to two days.
The health authority said boiling lake water will not remove the toxins produced by blue-green algae.
The ITU World Triathlon runs from from Sept. 2 to 4 at Hawrelak Park, and involves swimming, biking, and running.
WATCH BELOW: Coverage of last year’s ITU World Triathlon in Edmonton.