As the sun finally shines over Ontario and beach season commences, the question on everyone's mind is: How safe is it to swim in the province's lakes? With above-average temperatures predicted across the country, driven by a developing El Niño weather pattern, the demand for swimming and water-based activities is set to soar. But amidst the excitement, it's crucial to remember that conditions can change rapidly, and water quality is a critical concern.
The good news is that Ontario's beaches are generally safe for swimming, but it's essential to stay informed and be cautious. One of the primary factors affecting water quality is rainfall. Heavy rain can increase bacteria levels in lakes and rivers through stormwater runoff and strain on aging sewer systems. Toronto Public Health advises waiting 24 to 48 hours after a major rainfall event before swimming, as bacteria levels tend to peak immediately following heavy rain. They monitor water quality at 10 supervised beaches, testing for E. coli, a bacteria used as an indicator of other potentially harmful organisms.
The city's beach water quality standard is incredibly rigorous, at 100 E. coli per 100 millilitres of water, which is the most stringent in the world. However, officials emphasize that water quality can fluctuate rapidly from day to day or even hour to hour. Marie Curtis Park Beach and Sunnyside Beach, in particular, experience rapid changes in water quality compared to the other eight Toronto beaches.
Gregory Ford, vice-president of Swim Drink Fish and Lake Ontario Waterkeeper, highlights the importance of checking local beach advisories before heading out. While rainfall is a significant short-term concern, warmer temperatures and increased precipitation can also contribute to harmful algal blooms in some lakes and waterways. These blooms, often caused by cyanobacteria, can produce toxins harmful to humans and animals.
Ford advises beachgoers to be cautious if the water appears bright green or resembles 'split pea soup,' which can indicate a harmful algal bloom. Suspected blooms can be reported to Ontario's Spills Action Centre, which investigates potential outbreaks and issues public advisories when necessary. Ford emphasizes that climate change plays a significant role, as higher temperatures and heavier rainfall create conditions conducive to rapid algae growth.
Despite these concerns, Ford encourages residents not to let water quality fears deter them from enjoying Ontario's beaches. Instead, he recommends staying informed, checking local advisories, and being mindful of recent weather conditions before entering the water. While swimming is not prohibited when bacteria levels are elevated, exposure to contaminated water can increase the risk of infections and stomach illnesses.
In response to the upcoming beach season, Mayor Olivia Chow announced an increase in the number of lifeguards by 25%. The city has also been training additional lifeguards to ensure the safety of beachgoers. As the summer heats up, it's essential to remember that while the Great Lakes are swimmable, caution and awareness are key to a safe and enjoyable beach experience.
