Restoration of Hydrologic Functions of Streams Impacted by Milldams

Floodplain deposits upstream of milldams or other similar structures have affected the hydrologic function of eastern US stream channels. Stream restoration efforts that seek to restore channel profile stability and hydrologic function will require that both the channel and the floodplain be re-constructed to establish a floodplain with a vegetation root zone and a channel bed that is hydraulically connected to the gravel aquifer. Depending on constraints limiting floodplain excavation, two approaches may be taken: full-depth floodplain excavation and limited floodplain excavation. These techniques are based on the elevation of the gravel and bedrock that underlay the pre-settlement floodplains and the aquifer that they support.