We have an in-ground gunite pool, approx. 20 x 40, that is about 20-25 years old. We bought the house last year so this is our second season with the pool. Last year there were no problems. This year when everything was started up the pool leaks. Once filled, the water level will drop to about 2-3 inches below the bottom of the skimmer. When filled, water will flow out of the waste (?) drain pipe that empties in the driveway at a loss of about 1-2 inches overnight. The water appears to be flowing faster now, but that could be due to all the rain we have had in the Northeast if the water gets into the drain pipe (pipe broken and/or perforated to drain groundwater). Water has also been coming up through the ground in the backyard.

I have had the pool service guy try to diagnose the problem and he has plugged up various returns, etc., and the water level still drops. I assume that the leak/crack would have to be at or above where the water level stops dropping. Could this be a leak in the underwater light, the top of which would be in the general area of where the water stops dropping? I would think that if the problem was simply a crack somewhere in the gunite the water would not necessarily be running out of the drain pipe in to the driveway (unless of course it is a perforated pipe to also drain groundwater).

I am at a los at this point. The pool guy is supposed to come back and go diving at some point. Meanwhile he has it rigged with a device that continually fills the pool when the water drops to a certain level; so of course, my water bills are astronomical. Any thoughts, advice, help, etc., would be greatly appreciated.