Pool liner floated!

[Briankf]

We have an in-ground pool with a vinyl liner (don't know what's underneath that). It was built in 2003, we purchased the property in 2012. Two winters in a row the liner floated up in spring. The water leaked out to the level of the bottom step which would lead me to believe there's a leak around the steps. I called a pool store to check for leaks and they told me to fill the pool so the leak would be easier to detect. The pool has a pipe down the outside of the liner which we used to pump the water out from underneath. I filled it and realized that it didn't seem to loose any water in the week that I waited for them to show up. So I canceled the appointment and we used the pool all summer with no unusual lose of water. This happened 2 years in a row. The liner settles back down nicely when I pump out the water under the liner.

However, the bottom surface now is very lumpy. It seems that whatever is under the vinyl liner has been affected by getting soaked and has formed fairly hard bumps under the liner, various sizes from about 1/4" across up to maybe 1/2". We've just continued using the pool this way although it can make walking in the pool shallow area a bit uncomfortable in some spots. Is this something to be concerned about? Am I going to have further problems down the road if I just leave it? I know the liner is due for replacement soon but was hoping to put it off for another year or two.

 

[Texas Splash]

I suspect at some point you will need to investigate, but perhaps not until the day comes where the liner needs to be replaced, or you simply can't stand the feeling of walking on something that feels like the surface of the moon. Much depends on the base that was used (dirt, sand, padding, etc). When the day comes that you do pull everything up, that might be a good times to consider a sump pump or other drainage option around or under the pool to help prevent future pop-ups. For now, as long as it's holding water and those "lumps" are not becoming sharp, you should be okay.

 

[Divin Dave]

If your pool is leaking, it will leak year round. you can do a buck test to confirm if it is or not.

Depending on the depth of the water table, a good rain (or lots of melting snow), an raise teh water table aand/ or saturate the ground under the pool. This seems to be what is happening. A sump pump is likely the best resolution when it comes time to replace your liner.

 

[Briankf]

If your pool is leaking, it will leak year round. you can do a buck test to confirm if it is or not.

Depending on the depth of the water table, a good rain (or lots of melting snow), an raise teh water table aand/ or saturate the ground under the pool. This seems to be what is happening. A sump pump is likely the best resolution when it comes time to replace your liner.

The water level in the pool doesn't drop till the spring thaw starts to happen. With the climate we're in the pool probably has 1 to 2 feet of ice in it by the end of winter. I suspect it's the ice in the pool breaking up and pushing on the pool steps that cause the leak. There is a drain pipe (weeping tile) around the pool and a sump pump but it's not at the bottom level of the pool, only about 3 feet down and the pool is 8 feet deep. I don't know why the sump pump was put at that level but to change that now would be almost impossible as there's a concrete patio around the pool. The sump pump does run when there's been a lot of rain so the drain system does work to some extent at least.