The Simcoe Muskoka District Health Unit has issued a swimming advisory for the west beach at Sunset Point in Collingwood.
Testing at the site has shown an increased level of bacteria, prompting the health unit to warn against swimming in the water.
The beach was last put under a swimming advisory on July 25, after a town wastewater forcemain was damaged and pumped raw sewage into Georgian Bay at the harbour. At that time, both the east and west beach were posted with advisories, and the town posted swimming advisories at Millennium Park and the pier. All advisories were lifted on July 29.
Testing on July 29, Aug. 3, 4 and 5 at Sunset Point by the health unit showed acceptable levels of bacteria to allow swimming. Currently, there is no advisory for the east beach at Sunset Point.
The Simcoe Muskoka District Health Unit does routine testing of public swimming areas in the region, and posts notices to the beach advisory section of the website where water quality is impacted.
There are more than 50 beaches within the health unit's testing areas where water is sampled for E. coli bacteria. If the level of bacteria exceeds provincial guidelines, it's possible there is a higher risk of illness or infection and the health unit will advise against swimming and let people know the risk.
A swimming advisory will remain posted until sample testing shows bacteria testing is within acceptable limits. In cases where there is a significant risk to health and safety, the health unit will close the beach.
The health unit advises that even without a warning posted, water quality can change from day-to-day and hour-to-hour depending on weather and lake conditions.
Rain is a significant contributing factor to increased E. coli levels as rainwater drains from the ground into the water, bringing waste such as bird and animal feces, garbage, and chemicals into the water with it. The health unit recommends waiting 24 to 48 hours after a rainfall before swimming.
High winds that bring large waves can also increase bacteria levels by stirring up the lake bed. The health unit suggests to avoid swimming if the water is so cloudy you cannot see your feet when you are standing waist-deep in water.
Warm, shallow, slow-moving bodies of water and wet sand are other excellent breeding grounds for E. coli and other organisms.
The presence of waterfowl and their droppings can also have a significant impact on water quality, as can dead fish, algae/scum, or debris in the water that can increase the risk of illness or injury. Beach water may also be unsafe due to excessive weed growth and blue-green algae blooms.
Visit the health unit's safe water web pages for more information about the beach water testing program, to learn more about beach water quality and to view current beach advisories.