Water Quality Monitoring at Toronto Harbourfront

This summer I volunteered with Swim Drink Fish and have been helping out with their water sampling team. The Swim Guide stores all of the data from the water sampling team  – and is an excellent resource for figuring out if your local beach is safe to swim. I take water samples for E.Coli, measure the water temperature and clarity, and occasionally take a dissolved oxygen measurement. I also help with processing and analyzing the samples back in the lab.

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The City of Toronto has several combined sewer overflow (CSO) locations. During large rain events, stormwater overwhelms the sewer system, and the wastewater treatment plants cannot keep up with the inflow. There are a few locations with tanks that store the excess water during rain events. Even then, not all of it can be stored, and will overflow directly to Lake Ontario. This is a mixture of stormwater and wastewater.

All of that to say – there is raw sewage being dumped into Lake Ontario!

We don’t know how frequently this is being done – and there is evidence that the amount of overflows are reduced every year. It’s thanks

Bathurst Quay is one of these CSO locations. It is regularly not meeting recreational water quality standards for E.Coli – meaning yup there is too much poop in there for you to swim! Click here to see the Bathurst Quay past data.

The Rees Street Slip is another sampling location. The sailing school for the Harbourfront Centre takes off from here – so there are kids going in and out of boats all summer long. It has failed 34% of the time this past summer.

You can read more about CSO issues from the City of Toronto and from Swim Drink Fish.

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