Testing has shown that levels of Escherichia coli (E.coli) were within recreational water quality guidelines at most beaches monitored this week by Manitoba Water Stewardship.
E. coli counts were above the guideline at Gimli Beach on Aug. 11. Gimli Beach was re-sampled on Aug. 12 and results will be available online.
On Lake Winnipeg, weather and lake level information appear to be good predictors of E. coli levels. Bacteria counts tend to increase when strong north winds cause water levels to temporarily increase and large waves wash bacteria out of beach sand. When calmer weather returns, E. coli bacteria levels typically fall quickly to below guideline levels.
Algae blooms were observed this week at Killarney and Pelican lakes. On Pelican Lake (south), the concentration of an algae toxin, microcystin-LR, was above the recreational water quality guideline on Aug. 10. Pelican Lake was re-sampled on Aug. 12 and the concentration of microcystin-LR returned to below the recreational water quality guideline. Bathers are reminded to avoid swimming in dense algae blooms and to watch for advisory signs posted at beaches. Information on advisory signs is available online.
On Killarney Lake and at Pelican Lake (north), the number of blue-green algae cells was above the recreational water quality guideline but the concentration of microcystin-LR was below the recreational water quality guideline. Algae advisory signs are posted at these two beaches.
Algae 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 provide ideal conditions for blue-green algae to develop.
Bathers are reminded to avoid swimming in water where severe algae blooms are visible and to prevent pets from drinking water along the shoreline.
Results for all beaches across Manitoba are posted as they become available on Manitoba Water Stewardship’s website.
Visit the Manitoba beaches website for information on swimmer and water safety and what can be done to help protect beaches by following the water-smart precautions listed on the website.