As warm weather finally settles into Ontario and beach season gets underway, experts say the province’s lakes are ready for the summer crowd. Here is everything you need to know about beach and water quality this season.
With above-average temperatures expected across much of the country this summer, the demand for swimming and water-based activities will certainly rise.
“If you love going to the beach this is your summer, it’s going to be awesome for that,” Global News meteorologist and weather forecaster Peter Quinlan said.
Quinlan said the warm summer outlook is being driven in part by a developing El Niño weather pattern, which he said could strengthen into what meteorologists call a “super El Niño.”
The climate 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 waterfronts, 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 by placing additional strain on aging sewer systems.
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“The two big 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 major rainfall event before swimming, as bacteria levels tend to be highest immediately following 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 millilitres of water, which is the most rigorous standards 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 the other eight Toronto 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 should do so with caution and with the information at your disposal.”
While rainfall is often the biggest short-term concern, Ford said warmer temperatures and increased precipitation can also contribute to harmful algal blooms in some lakes and waterways.
The blooms, often caused by cyanobacteria, can produce toxins that may be harmful to humans and animals.
He said beachgoers should be cautious if water appears bright green or resembles “split pea soup,” which can be a sign of 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.
“Climate change is a massive impact,” Ford said, noting that higher temperatures and heavier rainfall create conditions that allow algae to grow more rapidly.
From Woodbine Beach and Cherry Beach to Centre 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 in a news conference Saturday adding that the city has “increased the number of lifeguards that we have by 25 per cent. We need more lifeguards and we’ve been training them.”
Ford said residents shouldn’t let concerns about water quality keep them away from Ontario’s beaches.
Instead, he encourages beachgoers to stay informed, check local advisories and be mindful of recent 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. Swallowing polluted water may also lead to stomach illness, including vomiting and diarrhea.
Beachgoers can check local public health advisories or use tools such as Swim Guide before heading to the water this summer.
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