After its dams came down, a river is reborn

The Elwha River starts at Dodwell-Rixon Pass, a high crack in Washington’s Olympic Mountains. There, a hiker who crossed would find the Elwha Snowfinger, formed by heavy winter storms and the avalanches that pour off the surrounding mountainsides. Wedged into a steep-walled gully, it forms the upper reaches of the Elwha basin.

If the hiker followed this snow down, eventually she’d find a stream, and that stream would widen and become the Elwha River. As she traveled down, as more streams joined its flow, she would find one of those messy rivers that characterize the Pacific Northwest: Wide, braided channels, scattered with logs and boulders, gravel bars strewn with detritus, a sense of a landscape half-finished.

Then the river would round a corner and flow out into an area of high gravel banks stretching on for yards, dozens of feet above the water. These are what’s left of Lake Mills, one of two reservoirs that once trapped the Elwha.

Beginning in 2011, the federal government removed this dam and one lower down, blasting them away bit by bit over three years. Dozens of researchers from the U.S. Geological Survey and the Lower Elwha Klallam Tribe, University of Washington and the National Park Service, along with universities across the country, have since documented how that removal affected sediment in the water, small mammals, salmon, birds and the ocean the river flows into.

The return of this unpredictable river offers a lesson for others looking to down dams that have passed their prime. In this wildness is resilience. Slowly, with human aid, the river is carving itself a new form with a better chance of weathering disruptions, including climate change. A new Elwha, unleashed.

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