What are the potential downsides to dam removal?
Dam removal does result in fundamental changes to the local environment. The reservoir will be eliminated, and with it the flat-water habitat that had been created. Wetlands surrounding the reservoir will also be drained, although new wetlands are often created both in the newly restored river reach above the former dam site and in the river below. Sediment that collects behind a dam, sometimes over hundreds of years, may contain toxics such as PCBs, dioxide, and heavy metals. Re-suspension of these toxic-laden sediments in the process of dam removal has the potential to damage downstream water quality and threaten the health of fish and wildlife and water users. Short-term impacts of the dam removal itself can include increased water turbidity and sediment buildup downstream if large amounts of sediment from the reservoir, are released, and water quality impacts from sudden releases of water and changes in temperature. These impacts, however, can be prevented through proper removal te
