Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? how deep can I go?

I'm assuming that you did a test on the clay to see how impervious to water it is. If the clay changes consistency or color, see if you can do another test. I thought I had good clay, then it quickly turned into a clay/gravel mix, with higher % of gravel the more we dug. We ended up going thru 2 different aquafiers (layers of sand/gravel) in the clay. The pond ended up with almost a 4' variance of water level (from Spring to late Fall) due to hitting the aquafiers and not being able to pack them closed.