The Grand River Conservation Authority now says current weather conditions are ideal for the formation of blue-green algae, but recent samples of water taken from the Conestogo Lake reservoir are well below the recreational guideline. The risk to human health is deemed low.
The Ministry of the Environment and Climate Change collected samples at the popular lake on July 20th when algae blooms were noticed on the shoreline.
Users should still avoid areas with algae mats on the shoreline as well algae scum floating on the water.
When blue-green algae dies it produces microsystin. If ingested, the toxin can cause such symptoms as headaches, nausea, sore throat, stomach cramps, and diarrhea.