Recent samples taken from Conestogo Lake have tested positive for low levels of algae toxins.
On Aug. 1 the Grand River Conservation Authority (GRCA) confirmed that July 20 samples collected at the lake by the Ministry of the Environment and Climate Change (MOECC) did contain microcystin toxins.
However, the GRCA added the toxin levels were “well below” the recreation guideline of 20 parts per billion.
“Based on these results, while the risk to recreational users of the reservoir in areas where no algae is visible is low, the [GRCA] advises that users should continue to avoid any algae mats on the shoreline as well as algae ‘scum’ floating in the water,” states the GRCA press release.
Officials say the weather conditions this week “are ideal for the formation of blue-green algae and reservoir users should be aware that blooms may appear at any time.”
Anyone who spots a blue-green algae bloom can call the Spills Action Centre at 416-325-3000 or 1-800-268-6060.
Those with health concerns after using the reservoir, such as a skin rash, should contact Wellington-Dufferin-Guelph Public Health at 1-800-265-7293 ext.4753.
“Algae blooms are a natural phenomenon” that “tend to occur during hot, dry weather,” officials say, adding “when the algae die, the toxin is released in the water, where it naturally breaks down in about five to seven days.”
More information on blue-green algae is available at www.grandriver.ca.
