Unfortunately, I have not enjoyed the lakes in Ontario, as I’m not certain if it is safe. However, when my son was born and I wanted him to experience being on a beach, we were told about Lake Simcoe and Sibald Point. We had a family outing there and it was lovely and water was clean. Our children had a wonderful time being in Lake Simcoe. We recently wanted to go back and were advised that the body of water was not swimmable..