Rocky, I opted out of the car bodies. I am in Oklahoma now working on the pond all this week. I decided to go with limestone boulders, earth terraces, 6" diameter mesquite trees cut and anchored in concrete, and the partial burial of 20 huge tractor tires. I got them for nothing, and they seem to be working out great. I wanted something that would not hurt a swimmer or a boat when the pond is low. I have young kids, and this pond will be next to the house. I'm trying to take pictures as we go along.
As for the watershed, the NRCS says I have 152 acres of watershed, which should be more than enough (according to them). But it really depends on the annual rainfall in your area. SW Oklahoma rarely gets enough. If you are in east Texas you wouldn't need near that much, but you might need even more in west Texas.
I'm learning a lot, and will start a completely different kind of pond on the same property as soon as I finish this one. Hopefully this winter. This one is very deep, and the next one involves damming a creek. I will be very long, nearly a half mile, but not so wide. It will flood oak forest, so I think there will be little need for additional structure. And it is a different watershed. Hope I live long enough to wear these ponds out.
Regards, Tom
