When dams go down, the beaches and the fish win
Hydro-energy is clean, cheap and reliable – in many ways, it’s every man’s dream: you get the reliability of fossil fuels with the eco-friendliness of wind and solar. But hydro also comes at a price, one that we are only recently discovering: it threatens biodiversity and encourages erosion. The removal of a dam on the Elwha […]
Hydro-energy is clean, cheap and reliable – in many ways, it’s every man’s dream: you get the reliability of fossil fuels with the eco-friendliness of wind and solar. But hydro also comes at a price, one that we are only recently discovering: it threatens biodiversity and encourages erosion.
The mouth of the Elwha River in Washington in March 2014 as the dam removal project sent sediment its way.
ANDY RITCHIE / NATIONAL PARK SERVICE
The removal of a dam on the Elwha River in northern Washington State – the largest such project in the United States – highlights the benefits that emerge after dams are taken down.
“We are seeing the rebuilding of an estuary and coast that were rapidly eroding prior to dam removal,” said Jonathan Warrick, a scientist at the geological survey and the lead author of a paper synthesizing the research, one of five on the project published in a recent issue of the journal Geomorphology.
The mouth of the Elwha in June 2014 showing the extent of the changes.
ANDY RITCHIE / NATIONAL PARK SERVICE
“Walking on this new land form that extends hundreds of meters toward the sea and changes every day — it’s fantastic,” he said. “It blows your mind.”
“The salmon have been coming back,” Dr. Warrick said. “They are spawning in portions of the river where they have not been for 100 years. And their numbers have increased a bit, too.”
