Pond Boss Forums POND CONSTRUCTION Soil questions New Pond Losing Water

We finished construction of a 1 acre pond in May of this year. The recent rains filled the pond and it overflowed as designed. In recent weeks, the pond has dropped nearly 5 vertical feet. The bottom was yellow clay and was packed with a dozer. There were no signs of gravel or springs during construction. We are counting on runoff from our land to replenish our pond. The water loss is much more than normal evaporation.
Is this common with newly constructed ponds? Can we expect it to hold water better once the bottom and dam are saturated or is this indicative of what we are stuck with? Any advice or feedback will be greatly appreciated. Signed: $8kInTheHole.