Testing has shown that levels of Escherichia coli (E. coli) were within recreational water quality guideline at most beaches monitored this week by Manitoba Water Stewardship.
Escherichia coli counts were above the guideline at south Pelican Lake (Pleasant Valley) on July 22 and at West Grand Beach on July 23, but resample results from July 26 taken at both beaches were within the guideline. E. coli counts were also above the guideline at Sandy Hook Beach on July 26, but counts fell below the guideline by July 28. Levels of E. coli were above the guideline at Gimli Beach on July 28 but had returned to within the guideline by July 29.
Exceedance of the guideline of 200 E. coli/100 ml at some beaches on Lake Winnipeg over the past week was likely caused by local weather conditions that caused increases in water levels and winds and waves to wash bacteria out of the sand and into the bathing water.
The number of blue-green algae cells was above the recreational water quality guideline at south Pelican Lake (Pleasant Valley) on July 23 and at north Pelican Lake (Ninette) on July 26 but the concentration of an algae toxin, microcystin-LR, was below the recreational water quality guideline at both beaches. Algae advisory signs are posted at both beaches.
Algae blooms were reported from a number of beaches along the east side of Lake Winnipeg during the past week. Results from samples collected at Victoria, Lester, East Grand and West Grand beaches were within the recreational water quality guidelines for the number of blue-green algae cells and the concentration of microcystin-LR, an algae toxin.
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.
Results for all beaches across Manitoba are posted as they become available on Water Stewardship’s website.
Visit the Manitoba beaches website for information on swimmer and water safety and what you can do to help protect beaches by following the water-smart precautions listed on the website.
