When I built my pond, I added a 2" PVC pipe under the dam and into the deepest part of the pond. Its there to let water drain out or possibly water cattle below the pond. Its not going to help with silting. The intake is similar to what this guy did (scroll to bottom): https://www.libertynaturepreserve.com/p40.htm which is a pipe with multiple small holes, surrounded by a large plastic housing filled with rock.

If you want a system that takes the dirty silty water off the bottom (and thus help some with silting), you need a bottom withdrawal system: http://www.georgialandsales.com/pdf/PondSiphonSystem.pdf

edit - I realize now I probably misunderstood when you said pond drain and thus the first section above does not apply.

Last edited by Redonthehead; 06/14/19 11:55 AM.
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