I can't offer any legal advice either, but I'll give you a scenario that happened on our place. It's kind of similar to yours.

At our pond we did some drilling ahead of the purchase of the property as well as a perc test for the Septic system. The drill returned depths of topsoil, clay, and limestone. The perc test was done with a backhoe. Although it wasn't directly in the pond build it gave a good visual of what the soil looked like down to say 6-8'. So, we kinda knew going in what we were going to do ahead of the purchase/build.

The limestone was the kicker. We knew ahead of the build that there was rock in the area specifically from the drill test. There is an old rock quarry caddy corner from the property, and the neighbor to the south said he built his basement on rock. How deep it is....no idea. Knowing it was there basically set the max pond depth unless I wanted to blast it out of there (no cheap) for additional depth. We also knew that we needed to have a clay liner over the rock to make sure the pond was able to seal. Our max depth is 11-12'. We never hit rock. Depth was accomplished by both excavation and building the pond dam higher than adjacent soils.

Now for your case. The part that I see as similar is your underground water table. Much like my limestone this sets your bottom depth and if you don't want a ground water pond you must have a way to seal the bottom, in your case clay. If you didn't know it was there previously it's basically a hidden condition. Digging the pond deeper may not help if you can't seal the pond due to water table. It's either raise the dam height or live with the max allowable of the soils/water table.

Not a pro in this area, sounds like a tough scenario to work through.

Not sure I would start stocking ahead of the final pond build at this point, echoing esshup's thoughts.

1.5acre LMB, YP, BG, RES, GSH, Seasonal Tilapia
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