FWIW, My 1 1/4 acre, 15 feet deep pond held water better each year for about four years after renovation and filling. It was explained to me that there is a wicking effect at the shoreline, and the sub-basin needed time to fully saturate to create resistance to seepage. The first year after filling it wasn't unusual for me to lose 1.25 inches per day, then it went to 1, then .75 and now it loses about .5 inches per day when the weather is dry (which is always). I'm not sure I'd be panicking just yet, but I'm far from being the expert on such things.
