We know about what the flooding has done to shorelines around Lake Ontario, but NEWSTALK1010 has learned that the bacteria washed into the lake from recent rains will potentially stick around for months.
"We probably will be looking at this for a minimum a few weeks, but possibly as long as October." says Jason Tetro, a scientist and germ expert.
He tells NEWSTALK1010 that when you have a large amount of rain, that's when the problems start piling up.
"Sometimes the storm sewers actually merge with the domestic sewers, so we actually end up with sewage run-off into the water."
Tetro says thanks to gravity, the bacteria can end up in the sediment of the lake and even in the sand on the beaches.
Another heavy rainstorm and that will all get kicked up again.
Should we be worried? Sort of, says Tetro.
"Don't be too afraid of the water, just don't drink it, and after you swim have a shower and scrub with soap so that if you did have any contamination on your skin, it will be washed off."
When it comes to what that bacteria might do, you may not want to know.
"You could end up with rashes, you could end up with boils and you could also end up with fungal infections which are also not too nice. " says Tetro.
There is a bit of a reprieve, and it comes in that big gold blob in the sky.
"Bacteria don't like the sun, so hopefully the sun will be able to keep the shallower areas a little bit more pristine, by killing off the bacteria."
The City of Toronto issued a statement with regards to the story:
- From June to Labour Day, the City of Toronto takes daily water samples from the supervised beaches across the city and tests for E. coli bacteria. When E. coli levels are high Toronto Public Health posts warning against swimming.
- It is generally unsafe to go in the water during or at least 48 hours after a rainfall, storm or flood. Please note that Toronto Harbour is unsafe for swimming at any time. The City of Toronto has extensive public education campaigns alerting people to this (signs on beaches, notices to boat clubs, website, twitter etc.)
- Why is it unsafe?:
- Stormwater is dirty – the rain washes away all that is on our roofs, streets, cars and other hard surfaces and washes it into our watercourses – this is the natural water cycle. In a naturalized setting, a lot of the rain and melting snow can also be absorbed into the ground, which acts as a natural filter. However, in a large, built-up city like Toronto with paved surfaces, water has little or no place to be absorbed, so it makes its way into the nearest storm sewer, picking up what is left behind… including grease, pet waste left on sidewalks, garbage, bacteria and other pollutants along the way before discharging into the nearest waterway.
- One of the other reasons, although not the sole source and not necessarily the primary source, is combined sewer overflow. Some of the City's older areas, where the sewer system was built as long as a century ago, have combined sewers in which there is only one pipe that carries both sewage and stormwater -- a common sewer design used by many municipalities at the time. During periods of intense, heavy rain fall however, the volume of stormwater that enters these combined sewers may exceed the system's capacity and some of the combined sewer flow (a mix of stormwater and sewage) must be diverted (or overflow) untreated, directly into creeks, rivers and the Lake. Toronto has the most significant infrastructure plan in place to ultimately eliminate Combined Sewer Overflows.
- The 2017 Wet Weather Flow Master Plan Implementation Status Update Report which is up for discussion at the Public Works and Infrastructure Committee on Tuesday and in it, there is a list of almost $3 billion in capital plans to help manage stormwater over the next 10 years.