Cherry Beach is one of Toronto's cleanest!
The Blue Flag Program has strict standards that Cherry Beach has followed for the last few years.

As the TWC is located in the waterfront park next to Cherry Beach, there are only a few occasions during the summer that the beach is considered unsafe for swimming. This usually only happens after a heavy rainfall that brings runoff from the Don River through the eastern gap and into Lake Ontario and past Cherry Beach. Depending on the temperature and wind / wave direction, polluted water may be pushed back then into Cherry Beach. Please check the city website
http://www.toronto.ca/beach/
with the water quality test results
http://www.torontobeach.ca/beaches/check.jsp
to make your own informed decision before windsurfing. You will also find water quality tests from the past few years there.
Click
here
for an overview of Learn to Windsurf lessons and water quality explained.
Weather forecasts are available from many sites and on marine weather radio stations. Check possible changing weather conditions before you go windsurfing, so that conditions are right for you and don't exceed your abilities. We recommend using the buddy system, whenever windsurfing.