pool changing area - you have those little rooms by the hot tub. Could be cute painted a clean white.
pool house hooks and bench
pvc frame idea - camp or outdoor shower. hang curtains for privacy, could hang black shower bag at peak.
Built in Idea on lower level entry for beach towels maybe. Closet full of beach towels right at hand at this Myrtle Beach, South Carolina home renovated by CRG Companies (via House of Turquoise).