How long can an on ground pool be empty before any damage occurs?

Answer 1

It all depends on whether there is ground water on the other side of the gunnite shell and how deep it is. Assuming the pool is 15 x 30 feet with a 4 ft shallow end and an 8 ft deep end and is rectangular, not rounded: the weight of the gunite would be approx. 87,000 lbs (6 inch thick@3.12gm/cc). An equivalent weight of water would fill the deep end pool plus another foot. If the ground water exceeded that level on the other side of the gunite the pool would pop out of the ground and float on whatever level water you have. If you drill a hole through the bottom or side of the pool 1 or 2 feet from the bottom the lift pressure will be relieved as water comes out and you will have no worries. Gunite is very strong and the pool can remain empty quite a while if there is no: water, land movement , earthquakes, or other mechanically damaging prospects.

Answer 2

Allowing the plaster finish to become dry will cause blistering and failure of the plaster. If you do not see visual signs of damage, get into the pool and tap on the walls lightly and listen for hollow sounds. You may or may not get any but after filling the pool the change will take place and the blisters will get larger and start decaying rapidly and in extreme cases will totally delaminate. No preventative measures here other than keeping the water in the pool and doing basic service by far this is the least expensive way of keeping the plaster and pool intact.

Ken

Answer 3

You have to be careful about about ground water tables in your area. now if you are draining it to take care of a issue look at the bottom drain later pools come with a port to allow the ground table to seek equal pressures of the pool verses the ground table do your repairs soon and it shouldn't be a issue.

During hot summer months a pool could possibly be pumped dry and left for up to 4 to 5 hrs. without too much damage. If the plaster is allowed to become too dry you run the risk of forming "blisters" or hollow places under the plaster surface at the gunite level. These blisters become enlarged and sometimes do not show up right away. And in fact it may be months before they separate or break off. They will continue to expand even though water has been reintroduced to the pool and after a while you get a small pop off which then enlarges. That is kind of the basics of it.

Answer 4

Damage can occur within four hours on a hot sunny.

That's only if your pool is plaster. The pool in question is gunite. A gunite pool can stay empty for as long as it takes to do the repairs, no long them a month. But you have to make sure, and this is very important, to open the plugs at the bottom of the pool to releave any water pressure that is under your pool, or your pool can lift out of the ground a couple inches. So remember to relieve the pressure relief valves at the bottome of your gunite pool as soon as possible. Our pool is 20 x 40, freeform, gunite inground pool. It's 3ft to 8 ft deep. As soon as the water is about knee high at the deep end, my husband walks in and removes the plugs at the bottom to release the water that is under the pool. It pours out for a few hours then slows to a trickle. The plugs stay open until we are ready to refill. Make sure, however, you put the plugs back in so they don't leak. He uses white plumbers tape around the threads of the plugs to secure a good tight fitting. Good luck, hope everything goes well.

Answer 5

If it is a pool with a vinyl liner, the liner may begin to shrink up as the weight of the water is removed from the pool and likely will not restretch. If it is a concrete pool, there are many variables including the water table in the ground around the pool, if there is deep freezing during the winter in the area, whether their is a hydrostatic relief valve installed in the pool, etc. A qualified pool profession should be able to take a look at the pool and offer some idea, but their are no promises that a solid shell pool (gunite, plaster, block, concrete, fiberglass, etc) won't float up and pop right out of the ground if left empty for any length of time.