Toronto's beaches are some of the best places to spend the summer months, but sadly four of the city's most popular waterfront locations are currently unsafe to swim thanks to high levels of E. coli.

The City of Toronto takes daily water samples from the supervised beaches across the city and tests for E. coli bacteria from June to Labour Day, and Toronto Public Health posts warning signs against swimming when levels are found to be higher than 100 E. coli per 100 ml of water. 

As of Aug. 5, testing shows that Marie Curtis Park East Beach, Sunnyside Beach, Hanlan's Point Beach and Kew Balmy Beach all have E. coli levels that exceed the City of Toronto's established beach water quality standard.

The highest amount of E. coli has been reported at Sunnyside Beach, with 495 per 100 ml of water confirmed over the past 24 hours. This is down from yesterday when 858 per 100 millilitre was confirmed. 

"Heavy rainfall and declining weather conditions indicate an increasing trend in E. coli levels," noted the city on Aug. 3.

Marie Curtis Park East Beach is next in line with an E. coli level of 265, followed by Hanlan's Point Beach with 209 and Kew Balmy Beach with 137.

It's common for Toronto beaches to report high levels of E. coli following heavy rainfall and flooding, and we've certainly seen quite a few storms in the city in recent weeks. 

"The public should not swim during and after storms, floods, or heavy rainfall," says the city. "Cloudy water can be an indicator of high levels of bacteria that may pose a risk to human health."