Clay, properly compacted, and build it with a core trench. Get it covered with something to keep the water from eroding it away again.

Here's some reading for ya.

http://www.sccdistrict.com/pond.htm

Make double darn sure that it is large enough to handle the water. Consult the NRCS office in your county for more specific information.

Last edited by Dave Davidson1; 06/15/13 04:47 AM.
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