Pond Boss Forums POND CONSTRUCTION Selecting a site Dewatering before digging

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

How is he going to seal the pond bottom/sides to keep the water in the pond after construction is completed?

I got nice clay down around the 6 ft area. already had a test hole dug. perfect pond material im told. hes gonna line the sides with it

Is he planning on compacting the sides and bottom of the pond?

yes that is the plan. He's built quite a few ponds. I've seen pics and he built one for a buddies friend. He was very happy with his work. I'm just curious of the dewatering part if anybody has come across that before.

On my first pond, the contractor dug a trench down the future bowl to a lower area to "dewater" the pond area. I installed a bottom drain on my 3rd pond to deal with a sand lens that continuously seeped water, but the area never really dewatered. However, I would not have been able to dig it without the drain. Sounds like this is not your contractor's first rodeo.