There is a reservoir system near my uncle’s house that has an old dam that has been bypassed in the watershed. You can see the wall of the original dam in the 3rd photo here. It’s getting taken over by trees on the downstream side. Upstream it appears to have filled in for the most part. The factory that originally used the dam is long gone, with not a trace left, other than this dam ands sluice way that has two waterfalls.