Water testing this week has shown that levels of Escherichia coli (E. coli) were within recreational water quality guidelines at most beaches monitored by Manitoba Conservation and Water Stewardship.
E. coli counts were briefly above the guideline at Lac du Bonnet and Winnipeg Beach (Lake Winnipeg) but quickly returned to below the guideline by Aug. 21 and Aug. 22, respectively.
Elevated levels of bacteria on Lake Winnipeg were likely caused by strong north winds and wave action washing bacteria out of the sand and into the bathing water.
Algal blooms were reported at Lake Minnewasta near Morden, Killarney Lake and Pelican Lake (Ninette and Pleasant Valley).
On Lake Minnewasta, the number of blue-green algal cells exceeded the recreational water quality guideline on Aug. 20 but quickly returned to below the guideline by Aug. 21. The concentration of the algal toxin microcystin remained below the recreational water quality guideline on both occasions.
On Killarney Lake, the number of blue-green algal cells was above the recreational water quality guideline. However, the concentration of the algal toxin microcystin was below the recreational water quality guideline.
Algal blooms are still present at Pelican Lake (Ninette and Pleasant Valley) this week. The number of blue-green algal cells and the concentration of the algal toxin microcystin remained above the recreational water quality guideline as of Aug. 20. Algal toxin advisory signs remain posted at Ninette and Pleasant Valley on Pelican Lake. Drinking, swimming or other contact with the water is not recommended. Additional samples will be collected next week.
Algal blooms are difficult to predict and may form and then disperse quickly, or last for several days or weeks. Warm and calm weather coupled with relatively high nutrient loads provides ideal conditions for blue-green algae to develop.
People are reminded to avoid swimming in water where severe algal blooms are visible and to prevent pets from drinking water along the shoreline.
Swimmer’s itch advisory signs will remain posted for the summer at Moose Lake Provincial Park, Winnipeg Beach (Lake Winnipeg), Whytewold Beach (Lake Winnipeg) and Gull Lake.
Up to date information on advisory signs posted at beaches is available online.
Information on results of beach water quality testing, and swimmer and water safety is available on the website.
