We live on a lakefront. The first thing we did was put up a fence before we took the dogs out without a leash. They love to swim. Gators can climb fences so we always check first of course. As mentioned, a gator is incredibly fast. Splashing really gets their attention. At night it would be very dangerous. That said, they tube and ski in our lake but do not seem to "swim" in the lake. Guess the boats spook them out of the way.
There is gator hunting in Florida but it is highly regulated and quite expensive for tags.
At Cape Canaveral they installed chain link fence and at the top they curved it backwards so the gators could not climb over.