This video is great.
Over 8000 dams in Pennsylvania have been removed making the state the nations leader in stream restoration. But is it working. There is a theory that mill dams and mill ponds as old as 400 years may be causing modern day erosion. Dorothy Merritts and Bob Walter of Franklin and Marshall College believe that many restorationists have misdiagnosed the actual issue. Erosion is key and residual (or legacy) sediments left over from mill pond removal erodes and allows streams to reconnect to their floodplains (a good thing for a fish and a bad thing if it takes out your house). As a test they removed a LOT (30,000 cubic yards) of dirt down to the presettlement level on a deeply incised stream. Native species are thriving! Floodplain reconnection was achieved, it didn't look like they added large wood either!.
From our own work I find that many restorationists want to stabilize banks and this video points out what I have long suspected, stable banks aren't necessarily a good thing.
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