For what its worth the pond book I have that shows how to build ornamental ponds warns against concrete in climates where there is freezing or thawing. It coincides with what Bill cody said.
I built a wood foundation for my log home specifically because all concrete foundations crack. They are also damp to some extent. My specially treated wood foundation with a pea gravel exterior is dry as a bone. No leaks whatsoever in 12 years.
Do you really need a liner or concrete? If your soil is not too porous, and you alter your banks to keep them from caving in, why bother? One added benefit of a natural soil pond is more natural conversion of nitrites to nitrates etc. And although I find my Chara growth annoying, and try to keep it thinned out, I have no doubt it provides addtional surface for nitrification and produces some oxygen during the day. And friend in the know says it provides a lot of habitat for forage insects also.
Last edited by Cecil Baird1; 03/03/08 10:52 PM.
