esshup's response had not yet posted when I started typing my 6:33 PM response. That is why I kind of covered some of the same points that he did, but in a slightly different fashion.
I was NOT correcting esshup's response. He is an actual pond expert!
P.S. My groundwater ponds also fluctuate quite a bit (4-5 feet). Are you wetter than usual over the past year? If so, it may be time to release your contractor for now, and have him come back after a hot, dry summer.
The demobilization costs for moving his equipment out, may be significantly less than the additional cost/hours that he has to put in fighting wet conditions. It never hurts to ask him.
