A sizable and potentially toxic blue-green algae bloom has been found just off the Innisfil shoreline.
The Simcoe Muskoka District Health Unit confirmed the discovery, which affects the southeast shoreline of Kempenfelt Bay (Bear Point area) and the southwest shoreline of Lake Simcoe (Innisfil Beach Park area), in a media release issued July 11.
It encouraged residents and visitors to “exercise caution” in the area.
Health unit Safe Water program coordinator Jenee Wallace also confirmed Thursday the bloom is why swimming advisories were posted at four beaches within town — Innisfil Beach Park North and South (676 Innisfil Beach Rd.), Leonard's (2715 Purvis St.) and Bon Secours (2407 Leonard St.) — starting on July 8.
Technically known as cyanobacteria, this algae consists of microscopic organisms that naturally occur in lakes and streams. They usually present in low numbers but can rapidly increase and form dense blooms when the water is warm, slow moving and full of nutrients such as nitrogen and phosphorous, the health unit says.
A possible bloom will appear green, blue, turquoise or olive green in colour. It may also look like scum, foam, mats or paint floating on the water’s surface, and smell like rotting plants or garbage, or rotten eggs.
There may be a presence of dead fish or other animals on the shoreline, too.
Confirmation comes days after the health unit initially said it was investigating a possible bloom affecting an area stretching from the Big Bay Point government dock to Maple Road.
In a social-media post issued July 9, the Lake Simcoe Region Conservation Authority said the Ministry of Environment Conservation and Parks Spills Action Centre has been contacted.
“Together, the Ministry and … health (unit) continue to conduct water testing and post beaches for safe access,” the LSRCA said in a social-media post. “Our Lake Simcoe research team is also out on the lake, monitoring and sharing our findings with the Ministry team and our municipal partners.”
The health unit recommends taking the following precautions around blue-green algae:
- If you see a bloom, stay out of the water, and keep your pets out as well. You cannot tell if a bloom is harmful by looking at it, so it's best to use caution.
- Do not drink the lake water or use it for cooking, including infant formula preparation and ice making, unless it has been treated by a municipal drinking water system. Municipal systems are tested regularly for safety.
- Do not boil and drink water that may contain blue-green algae because toxins are not destroyed. In fact, boiling may increase toxicity.
- Do not use herbicides, copper sulphate or other algaecides that may break open algae cells and release toxins into the water.
- Do not fill pools or spas with water directly from the lake.
“Many species of blue-green algae have the potential to produce toxins that are harmful to the health of humans and animals,” the health unit says. “Symptoms following contact or consuming toxins from a blue-green algae bloom can include irritation of the skin, eyes, nose, throat or lungs, stomach pain, headaches, diarrhea, vomiting and in severe cases, liver damage. Symptoms can be more serious if water is swallowed in large quantities. If you suspect a blue-green algae bloom, be cautious and assume that toxins are present to avoid exposure.”
Anyone who sees a potential bloom is encouraged to report it to the ministry online or by phone at 1-866-663-8477.
