As warm weather finally settles in Ontario and beach season begins, experts say the province’s lakes are ready for the summer crowd. Here’s everything you need to know about beach and water quality this season.
with above average temperatures are expected in most of the country this summer, demand for swimming and water-based activities are sure to increase.
“If you like going to the beach, this is your summer, it’s going to be great for that,” said Global News meteorologist and forecaster Peter Quinlan.
Quinlan said the warm summer outlook is being fueled in part by a developing El Niño weather pattern, which he said could strengthen into what meteorologists call a “super El Niño.”
The weather phenomenon is associated with warmer-than-normal temperatures, with forecasters expecting much of Southern Canada to see above-average warmth through June, July and August.
As beachgoers flock to Ontario’s waterfront, experts say the good news is that the province’s beaches are generally safe for swimming.
However, conditions can change quickly depending on weather and environmental factors.
One of the biggest factors affecting water quality in Ontario is rainfall.
Heavy rain can increase bacteria levels in lakes and rivers through stormwater runoff and putting additional strain on aging sewer systems.
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“The two biggest ones are temperature and rainfall,” said Gregory Ford, vice president of Swim Drink Fish and Lake Ontario Waterkeeper.
Toronto Public Health (TPH) advises waiting 24 to 48 hours after a heavy rainfall event before swimming, as bacteria levels tend to be higher immediately after heavy rain.
The agency monitors water quality at 10 supervised beaches throughout the summer by testing for E. coli, a bacteria used as an indicator of other potentially harmful organisms that may be present in the water.
The city uses a beach water quality standard of 100 E. coli per 100 milliliters of water, which is the most rigorous standard in the world.
However, officials say water quality can change rapidly from day to day or even hour to hour.
“Water quality at Marie Curtis Park Beach and Sunnyside Beach fluctuates rapidly unlike Toronto’s other eight beaches,” the agency said in a statement.
Ford said checking local beach advisories before heading out is one of the easiest ways for swimmers to stay informed.
“The Great Lakes are absolutely swimmable places,” he said. “But you have to do that carefully and with the information you have.”
While precipitation is often the biggest short-term concern, Ford said warmer temperatures and increased precipitation could also contribute to harmful algal blooms in some lakes and waterways.
Blooms, often caused by cyanobacteria, can produce toxins that can be harmful to humans and animals.
He said beachgoers should be wary if the water looks bright green or resembles “pea soup,” which could be a sign of a harmful algal bloom.
Suspected blooms can be reported to the Ontario Spill Action Centre, which investigates potential outbreaks and issues public advisories when necessary.
“Climate change is a massive impact,” Ford said, noting that higher temperatures and more rainfall create conditions that allow algae to grow faster.
From Woodbine Beach and Cherry Beach to Center Island Beach and Sunnyside Beach, Toronto’s waterfront is expected to draw thousands of visitors looking to cool off after a long winter and during what forecasters say could be a warmer-than-normal summer.
Mayor Olivia Chow also commented on the upcoming beach season at a news conference Saturday, adding that the city has “increased the number of lifeguards we have by 25 percent. We need more lifeguards and we’ve trained them.”
Ford said residents shouldn’t let water quality concerns keep them away from Ontario’s beaches.
Instead, he encourages beachgoers to stay informed, check local advisories and be aware of the latest weather conditions before heading into the water.
Although swimming is not prohibited when bacteria levels are elevated, Toronto Public Health says exposure to contaminated water can increase the risk of ear, eye, nose, throat and skin infections. Ingestion of contaminated water can also lead to stomach ailments, including vomiting and diarrhea.
Beachgoers can check with local public health advisories or use tools such as Swimming guide before you hit the water this summer.
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