My Watermark is Lake Ontario.

It amazes me the number of people living in the GTA who are surprised that you can swim in Lake Ontario. Yes, it's warm enough to swim from the end of July to the end of September, and the water can be clean and clear - it just depends on where you get in. Obviously the shoreline in highly populated areas can be foul and full of debris, but there are some pleasant surprises including some nice beaches, provided they are not overrun by geese and other waterfowl.

The best place nearby to take a refreshing dip in the lake is away from the shore, from the back of a boat. Still, it's rare to see swimmers out there and not everyone has access to a boat. Fortunately we do, and we encourage everyone we take out sailing to enjoy a dip in the lake, an epiphany for those who don't think it was safe to do so.
Maybe if we all swam in the lake, we would be more appreciative of the beautiful resource we have at our doorstep, and have more respect for the way we treat it.