Pond Boss Forums POND CONSTRUCTION Selecting a site Watershed for 2.4 acre pond

I think in your situation, the logical way to go about it is to use a liner to minimize any seepage through a clay liner. Water evaporation is going to be high, and it sounds like a 4" well will be all you need. In any case, I'd double screen the well, both to expose more area to the aquifer, and to lengthen the longevity of the well. If you can, use a stainless, not plastic screen. They perform better.

I agree with the NRCS in making sure you have a large enough emergency spillway. You don't want a 500-1,000 year rain event to blow out the dam and require repair of both the dam and the liner.

I would dig it as deep as your pocketbook allows. You will have to cover the caliche with some sort of padding to help prevent it puncturing the liner. Also deeper means more water in the "bank" so to speak during times of drought.

Look at Bend Tarp and Liner. They have a woven fabric liner that looks to be pretty good. I've never used it, but the sample that they sent me was tougher than urethane liners.