teeroy, welcome to PondBoss. Howdy neighbor. We're just a few hours away near Dolores,Co. My brother and sister in law, and our son and daughter in law are just down the hill by Fanta Se, as they like to call it. Our drive to visit them sometimes takes us through Espanola.
Dry dry dry where you are, isn't it!
What kinds of stock water impoundments are in your neck of the desert? Is there anything close to the size, as in volume, of the pond you're considering? I ask because a dam 10' tall may be more than you need to capture the meager snowmelt and monsoonal rain that falls by you.
I like your idea of using the block wall and rebar, then backfilling, with a liner to hold the bit of surface water you get there. My cautionary tale is that here, with our clay soils, our 3" to 2' of snow, and monsoon generated summer rain does not affect the depth of our 1/4 acre pond in any significant way. We get a small flow of runoff from rain; nothing from the snow melt. We've got 3 significant draws joining our pond with fewer than 50 acres of watershed. Our pond is irrigation water fed.
Good luck with your project. If you like, I can swing by on one of our trips to NM.
Roger
