Fiberglass Bottom Buckling/Raised?

[Beach_Bum_at_Heart]

I came home last night from work and noticed the floor of our fiberglass in-ground pool has raised about three to six inches off the ground. I’ve been describing it to local repair folks as a large pillow below a blanket. I thought I had a leak when I opened the pool, but it may have been evaporation; or the two events are correlated. I’m really not sure.

I’m trying to find someone in the area to come out and provide an estimate, but I’m wondering what I should anticipate with any estimates I may get — cost/cause/repair process?

 

[Texas Splash]

It's hard for me to see the bubble in the image because the shadow is messing with my view/focus, but from your description that is an amazing increase you are seeing. I would think there must be a significant rise in water underneath the pool to generate that much lift. I've never experienced a repair like that myself, but I would expect first & foremost the pool company will want to identify, isolate, and repair the root cause for that rise and try to eliminate further upward pressure. If it's one of your own pressure lines, that would be digging down to the plumbing to repair the line and any concrete/coping around that area. If you're in an area with a high water table, or received an unusual amount of rain this years, subsequent hydrostatic pressure relief or perimeter draining might be pursued. For the pool itself, they might have to drill some relief holes to prevent additional rise (patch afterwards), unless they believe the water pressure alone will push the pool back down once the issue underneath is resolved. I suspect this will be a bit of a headache for a few days, so have plenty of aspirin ready and think positive. There's always a chance that upon review, the outlook won't be so bleak and the repair process might be better than we fear. I hope so. Let us know what you learn, and good luck.