Blue-Green Algal-Bloom - Forest Lake

Dec 13, 2024 Update: 

The resample of the Forest Lake water conducted by Ontario Clean Water Agency (OCWA) demonstrated a “no detectable level of the microcystin” (0.1 µg/L which is less than the method detection limit). The water resamples results collected by OCWA on November 1, 2024, November 6, 2024, and November 12, 2024, showed no measurable microcystin toxin level (0.1 µg/L less than the method detection limit) from Forest Lake at the sample locations. However, the Health Unit continues to advice people drawing surface water to continue to take precautions.

The Health Unit was informed of the presence of microcystin toxin (0.2 µg/L ) detected in the raw water sample taken from Forest Lake by Ontario Clean Water Agency (OCWA). This testing was conducted for the South River Water Treatment plant and sample was taken close to this area. The treated water did not have the microcystin. At this time OCWA informed that the matter has been reported to Ministry of Environment. OCWA plans to continue testing and reporting microcystin levels in both raw and treated water for the next two consecutive weeks. OCWA also reports that there was no sign of an algae bloom on the lake when sample was collected.

We are therefore notifying the township because of the possibility of residents that might be drawing water from Forest Lake. Kindly notify residents that are not using the municipal water supply to take extra caution and to use alternate water supply for drinking.There is a lack of an effective treatment system capable of removing toxins in private domestic water systems.

For further information, those residents that are not using municipal water can be directed to the Health Unit website to read more about Cyanobacteria (algae bloom). Here is a link for the information: https://www.myhealthunit.ca/en/health-topics/harmful-algae.aspx