Well, you can carry while your swimming, just get one of those water proof boxs.
This is what I will do when I go to the beach and go swimming.
But not here, the water is black and if you go in you might not come out!
Just keep non in the chamber and wrap a towel over it so if people see your case they cant see your gun. Place keys/Id/Ccw etc.. in there, one large strap to your leg/arm and a floaty/orange flag to spot it.