Is there an issue with doing a clay liner with a high water table? You have mentioned that and I believe right now that a clay liner would be my best bet.
No issue with the clay liner (unless you have very strange circumstances). Basically, if you get your pond sealed with clay, any movement of water through your aquifer will try to go AROUND your pond.
The big issue will be CONSTRUCTING your pond in an area with a high water table. Wet ground is always a hassle for heavy construction equipment. Wet ground with clay involved is even worse.
Your contractor may have to dig a deep pit above your pond location and run a big pump to draw down the groundwater enough to excavate and line your actual pond location. That is feasible for many groundwater tables, but will add to your expense. (It will also add to your expense even if you do a liner pond.)
Also for the drain tile, would there need to be an "electrified pump" installed with this? Ideally wouldn't like to mess with electric if I don't have to, I feel like the sump pump for the pit would be going off all the time as well.
I was thinking that a high ground water table ballooning your liner would be a "rare" problem. I have a 2" gas-powered trash pump that I use to occasionally move water at our property. (Cheap one like mine is currently $450 at Tractor Supply for 150 gallons/minute.) They work very well in that type of application. I have filled mine with gas and left it running while I did other work at the farm.
