Pond Boss Forums POND CONSTRUCTION Soil questions New lake on sandy soil (existing stream bed)

Welcome to the forum. I think your gut feeling is correct. How far below the ground surface is the water now? i.e., if you dug a hole in the ground and didn't pile any dirt around it, how far down would the water be from the surface?

My pond is like that. We dug in sand, hitting a thin layer of clay at 11'. Water was above the clay. We dug thru the clay and hit a solid band of clay at 20'. During the Spring, test holes would have water in them at 3' below the surface. I have had water levels drop around 5' from the surface. There wasn't enough clay available to seal the pond, so I have to live with it fluctuating in level, or use the well to keep it full.

With the stream running thru the pond, whatever fish are in the stream (both present and future) will end up in your pond unless you detour the stream around the pond.