I have been reading a lot but first post. Lots of information to take in here. One thing that I find interesting is all the questions on the water table and a pond being built that will fill then empty again due to this, I might actually be in this situation myself, time will tell. I am curious, if you had water break through the bottom of a pond and it filled from the water table, or an aquafier, has anyone tried putting a pipe with a flapper or check valve in the hole the water makes it's entry into the pond through, something along the lines of like a toilet tank sort of idea? Merry Christmas to all!