Probably a retension pond built to contain storm runoff within that community.
Lots of them thruout Florida, with some being very large.
I was surprised recently at seeing quite a few what i thought to be Bluegill beds at one near my home which isnt very large, maybe an acre or so, and also less than 5 years old.
Many of these are fenced and off limits, but could well be good places for shore bound fishermen.
I suppose with all the billboards along the highways for the trip and fall lawyers, thats not apt to change.