I hate to give a specific location because the swimming up here is generally good most anywhere and especially good in some the the bays. The picture I posted was taken at 50 09.603N 124 46.118W.

I did a bit of swimming where this photo was taken also and it was great. 50 19.527N 124 47.4W

In general, anywhere up here, but if you go farther north, through the rapids, the water temp will plummet.

The tides here come around Vancouver Island from the north and south and meet here, so there is minimal exchange with the cold west coast waters.