People are susceptible to brain-eating amoeba.
Jeremy is correct. And do whatever you want, but technically it's a no for humans. The water gets pretty darn warm as well, so I don't know how safe it is for humans. The back water area, like Jeremy said, used to be a public beach. They still have the functional showers set up. Might be because there is no life guard, and therefore a health liability? Not sure. You could call the park and get your answers direct, rather than from second hand sources.
There are two separate areas to "swim." One is specifically for dogs, the other (in the back of the park) was shut down from human swimming years ago after a hurricane knocked down trees and fences/wooden walk ways and debris in the water. It's been off limits to people ever since. That's was I was told by a friend. Edit: maybe the dog lake is separate from the human one because they're worried about dog waste in the water?
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