A core is something like this, only wider. It's tied into soil at the ends of the dam that don't let water thru, and is tied into the same type of soil under the dam. It's usually made from clay, and compacted in layers as it's placed to ensure that it won't let water thru it.


The PB member that took the picture was digging thru his dam to find a leak.

There's another picture of a cross section of a dam here: http://www.aces.edu/pubs/docs/A/ANR-0195/anr195two.html

Last edited by esshup; 04/12/13 04:57 PM. Reason: added link
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