There are a few in Pinellas....
Largo-Walsingham Paws Park
Ft. DeSoto Dog Beach (too cold now)

There is a really nice water park in St.Pete that does boarding, day care, grooming and what not, that is VERY NICE!!
They actually converted a 1500 sq ft home into 4 seperate suits that you can board your dog in each with soaf, tv, all the ammenities of home..
The kennel area is climate controlled too