Mysterious water in empty pool

[PoolDoc]

Obviously, you don't live around here! We've had enough rain, so that the question would be, "Why is there ONLY an inch of water?".

That's partly the problem -- water explanations are very local -- not just to the area, but to YOUR pool. If you can, a knowledgeable LOCAL service guy is going to be able to guess at the right answer a WHOLE lot better than we can here.

[mas985]

You may have a hydrostatic valve in your main drain and when water builds up underneath the pool, it opens the valve and lets water into the shell. This is done on purpose so that when the pool is empty and there is water under the shell, the shell won't float which can destroy the shell.