Any logical explanation for pool losing water over winter?

[BPool5]

I have an Intex pool, 15' X 48". This is my second winter with it. Last winter I plugged the inlets and removed the pump, used the pillow and got a decent cover. In spring water level was fine and just had to balance chemicals. I don't recall having to add any water but maybe a little. This year someone told me I should drain water below inlets so I did that and again pillow and cover. I'm in Chicago area so the water in pool has been pretty much a block of ice and snow all around the pool. A few weeks ago we had a nice day and I ventured out by pool and noticed the water level has dropped by about 4" below the inlets. I assumed there was a leak and thoroughly examined the exterior of the pool to determine where it was coming from and don't see anything. Assumed it was under the pool and I'd spend the rest of the time until opening seeing the water level continue to drop and end up with an empty pool. But the water isn't dropping any more. Every few days I go outside and peek under cover and it's still about 4" down. Is it normal to lose water over winter?

 

[Newdude]

It could be happening/happened a few ways. Either the cover is so saturated that the pool water is flowing right through it and evaporating, or the weight of the snow/ice on top of the cover pushed down on the pool water and it went up the sides and out the edges of the pool or out the skimmer (etc) if open. It likely happened before the pool was a brick of ice, but also could have happened once it started to thaw.

Keep an eye on it. It's entirely possible that it's ok.

 

[JoyfulNoise]

If you’re not in danger of freezing, you could always fill it up to where it started off and see if there is a leak.