My pond builder wants to install 4" field tile around perimeter of the 3/4 acre pond to be built. attached to a sump pit and pump the ground water out the overflow pipe to the creek for a couple months. His theory is it keeps the pond area dried up and easier for digging. After completion he turns the sump discharge around to pump the ground water into the pond thus helping it fill without the ground pressure possibly busting thru. Has anyone else done this during their build? Pond will be 20 ft.deep