Water Level Mystery

[FDSJr]

I have a mystery with my pool water level. I have an inground pool (16 x 36) with a vinyl liner and one skimmer. The water level in the pool was sitting at the top of the skimmer due to some recent rains a few days ago. Then we had 8 inches of rain in one day due to the remnants of Hurricane Ida. During and after this 8 inches of fairly constant downpour, by water level remained at the top of the skimmer - no higher and no lower. The rain stopped a couple of days ago and the water level is still unchanged. I could be wrong, but it seems to me that the 8 inches of rain should have caused the level to go up, but that didn't happen. And, it also hasn't gone down.
My local pool dealer suggested "displacement", but to the best of my knowledge that normally takes place in the winter due to the weight of snow and ice on the cover and seems totally unrelated here. Their only advice was to keep an eye of it for a few days and see if the level goes down more than normal and, if so, they will check for leaks.
Has anyone else ever encountered this mystery? Any thoughts on what might have caused it?

 

[mknauss]

Does the pool have a drain that is located at the top of the skimmer level? Some are along the water line, inside the skimmer throat, or within the skimmer body itself.

 

[SecoSteve]

I'm also in PA and when that storm hit, the rain almost immediately raised my level to near the top of the coping. Luckily, we didn't have any long lasting power outages, so I was able to drain from the hose bib at the pump. You must have an auto drain located at the top of your skimmer somewhere.

This first season with the new pool, I had to drain some water 2 times and add water 2-3 times. When we built, I had no info on auto fill and drain, because I wasn't TFP experienced yet.

 

[SouthwestOhio]

Interesting.........my PB told me that that excess water during closure- winter months, would find its way out through the skimmer body and the the "joint" with the adjustable upper part of the skimmer assembly which contains the clean-out lid. The upper part slides up and down to allow for adjustment with the finish grade of the pool deck or copping. If memory serves me- Im not home to look, that seam or point of contact between the upper adjustable assembly and the fixed skimmer intake is probably right about the top of the skimmer intake level. Could the excess water have been drained off through this "joint" and found its way into the granular backfill and into the under drain?