Steenburg Lake Community Association

What can happen if Phosphorus levels rise


This information below is from the Muskoka Lakes Association showing what can happen if phosphorus levels are allowed to rise.

Algae Bloom on Three Mile Lake

December 23, 2005 Advisory Lifted by Simcoe Muskoka District Health Unit

On 23 September, the Simcoe Muskoka District Health Unit identified a severe bloom of blue-green algae (cyanobaceria) in Three Mile Lake, near Windermere. It was determined by the Health Unit that this particular algae is a rare type that produces toxins. These toxins can cause severe gastrointestinal symptoms (diarrhea, abdominal pain, nausea and vomiting) as well as headaches, fever and itchy skin and eyes if the water comes in contact with the skin or is ingested.

Three Mile Lake is surrounded by farmland and has hundreds of cottages on its shores. Its water exits the lake through the Dee River into Clarke’s Pond and finally enters Lake Rosseau over the Dee Falls. There have not been any reports of cyanobacteria entering Lake Rosseau, as water levels are very low.

Although the MLA does not monitor water quality on Three Mile Lake, the 2005 MLA water quality initiative has shown that average water temperatures were several degrees warmer than they were in 2004 across the area monitored by the MLA. The District of Muskoka reports very high phosphorus levels in Three Mile Lake. These two conditions likely caused the outbreak of cyanobacteria.

District and Township staff are meeting on October 13 to discuss remedial actions for the lake. Further public meetings may also be held. Please go to the Simcoe Muskoka District Health Unit website for official information regarding the status of the algae bloom.