Any one here ever have an issue with losing water over the winter that ultimately wasn't due to a liner or plumbing issue? Closed up on October 23rd, '14 and didn't really get to consistent freezing temps until late December early January. I'm guessing I've lost about 9-12" of water since closing. Used a new "solid" tarp like cover. I know water can still seep through it though and wasn't sure if it could be evaporation. That's why I mention the water didn't really freeze up until early January this year.
I've poked my head under the cover in about a dozen spots and there's no visible liner failure along any of the wall surfaces. I was able to see every square inch of wall surface to the bottom, so didn't miss anything. All lines were blown out and capped. Dropped the water level below the skimmer, but still above the returns when closing. Water level since close dropped about 4 inches below the returns (9-12" total), so if it's a leak I don't imagine the returns or skimmer being the cause since it went below them a good amount. No lights either. There is a functioning floor drain in the 8' deep end, but that was also blown out.
I really didn't keep my eye on the water level after closing, plus come January there was snow on top. So I don't know when and how quickly the loss occurred. I'm roughly estimating that it's about 4-5k gallons lost for the amount of drop. Only have about 2.5' of concrete decking around the pool, so I feel if it was a leak there would likely be some signs in the yard of water for the amount lost, though I suppose it could have been a slow leak.
Just filled it back up another 5-6" of water today, so I'll track the water level over the next few days to see if there's a change. I'm hoping that evaporation can explain it, but couldn't find any other threads searching the forums with people in my climate losing this much water. Most of what I found ultimately ended up being damaged liner or pool light when I did my search.