Most hold water very well. One of my neighbors built a stock tank and was very glad to have hit a "spring" (seep) at 12'. I have not had the heart to tell him that it might not be so good. In any case his stock tank filled up and still has 6' of water with it being almost 5 months without rain. one other neighbor which is higher elevation hit rock from 1/2 to 3' in diameter. The pond was built deep and holds water fine below the dam level but seeps through the rock dam. It still has several feet of water in spite of the fact I can see rock down as deep as vision allows. The closest pond to me the dam looks like it has exactly the same material as mine. It is 45% full despite drought.
Where would I get the clay to pack around wet spot? Hire a backhoe to dig down to the clay layer?
