Air buble under liner

[Cuatro]

Pool has neen installed and working good for 40 days or so, filled it up week after July 4 th weekend.

kids noticed a air bubble in the level area of the shallow end. We took lots of care to install and get the liner all installed and it was not there for at lease 40 days. Where could that be coming from?

it worked its way up side but puzzling on why and how it got there.

 

[Mike1162]

It may be water not air. Have you had lots of rain recently?

 

[Cuatro]

Yes
18" over last week

 

[Mike1162]

If the level of the ground water gets close to the level of the pool water then the liner can get loose & you'll get water under the liner. Your pool must have been overflowing.