I recently spent a month vacation in St. Pete Florida, and was torn on the salt water. While I never fully submerged, naturally my hair got somewhat wet/damp and I didn't have a problem. I detached, shampood (I use RemySoft), and reattached (ORWG for front and Got2B Ultra (not tape) for the rest) once per week and it was fine.

The humidity there actually made my hair look great, wavy, and shiny (even if it felt kinda bad). I also used PPI Enhance and Argan Oil, along with a cold blow dryer in the morning to refresh the look. Your mileage may vary, no hair loss. If anything the SUN did the most damage, had to get a color when I got back.

Swimming pools... I think that's dangerous no matter how you look at it, even with a cap. In my pool I'd be okay, I'm pretty light on the chemicals, but I wouldn't ever go under in a public pool (where you come out smelling like a chemical lab).

I've attached a few of the rougher looking pics from my trip, and one where I got rained on.