Swimmers and waders are being advised to stay out of the water at Rainbow Beach and Lakeside Park Beach on Alta Lake in the Whistler area.
The warning comes as Vancouver Coastal Health (VCH) posts an advisory due to elevated E.coli bacteria levels at the beaches.
Dr. Paul Martiquet, Sea to Sky's medical health officer, said the likely cause of the elevated E. coli levels is wildlife contamination.
"It can come from several sources," he said. "Geese droppings can contaminate the water, for example."
The long, hot, dry spell Whistler has enjoyed also played a part.
"Closing the beaches is more pre-cautionary than anything," said Martiquet, adding that the elevated levels were discovered through the regular testing that is done. As soon as levels go down, likely in several days, the beaches will be re-opened. Testing at other local beaches show levels of E. coli at acceptable levels.
High levels of this bacteria in the water increases the risk of gastro-intestinal illness to swimmers who quite often swallow lake water as they swim and play. Bathers can also get swimmer's ear, though that is not common. The ear, nose and throat region can also be affected. Anyone with symptoms should see a doctor said Martiquet.
The Resort Municipality of Whistler (RMOW) has posted signs at the beaches to notify users and VCH is working with the municipality to monitor the water quality. The beaches will re-open for swimming once the levels have decreased.
This is the first time in more than a decade that a Whistler beach has closed due to high E-coli levels.
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