Mine goes over the top of the skimmer pretty frequently due to heavy rains. My pool is only 48" so I like to keep it topped off. The skimmer doesn't work correctly if it goes above the line but that isn't the end of the world if you just backwash it back down to level. More of a concern is that water overflowing the skimmer can erode around and under the bottom of your pool if you let it go on too long.