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60-Second Earth

World's Largest River Restoration Project Begins

The removal of two dams on the Elwha River will help restore once-abundant salmon runs. David Biello reports

Ninety-eight years ago, engineers tamed Washington State's Elwha River. Dams provided electricity, at the expense of runs of five types of Pacific salmon. But the fish should soon be back. 

The two dams on the Elwha are coming down, part of the largest river restoration project ever undertaken in the world and a pointed contrast to the burgeoning number of dams being built around the world. Among other highlights will be the removal of the 21-story tall Glines Canyon Dam—the tallest dam ever taken down.

The restoration will also require careful treatment of the sediment that has built up behind the dams—so as not to bury Olympic National Park or the communities downstream with decades of silt.

Once the $325 million project is completed, locals will greet returning pink, Chinook, Coho, chum and sockeye salmon—as well as the animals that rely on them, like black bears and bald eagles. And sandy beaches may return to the Elwha's delta in the Juan de Fuca Strait.

The first chunks of concrete have been removed from the dams, which will slowly be eaten away over the next few years. At which point, the Elwha River will flow freely for the first time in a century.

—David Biello

[The above text is a transcript of this podcast.]

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