On the Elwha, a New Life When the Dam Breaks- page 3 | People & Places | Smithsonian
Two antique dams on Washington state's Elwha River are set to be demolished. (Brian Smale)

On the Elwha, a New Life When the Dam Breaks

A huge dam-removal project will reveal sacred Native American lands that have been flooded for a century

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But despite its spirited appearance, the Elwha is barely alive. Only the five miles of habitat below the dams is currently accessible to salmon. Historically the river produced some 400,000 wild adult salmon annually; today it’s closer to 3,000.

The exile of the salmon has meant the banishment of other animals that otherwise would feast on the fish. The area’s populations of bobcats, bear, mink and river otter have likely declined. In similar ecosystems in nearby Canada, there are “bald eagles like mosquitoes,” Young says. But they appear to be much more rare on the Elwha. Since salmon carcasses aren’t fertilizing riverside vegetation with nutrients brought upstream from the ocean, even the cedars starve.

Pat Crain, a park fisheries biologist, snorkeled portions of the Elwha a few years ago, drifting “like a log” down the river and tallying all the living creatures he encountered by making hash marks on a piece of PVC pipe strapped to his arm. He glimpsed thousands of rainbow trout above the dams, but “there were long stretches where we saw virtually nothing.” Just mile after mile of perfect, deserted salmon habitat.

Yet the one snippet of river that the fish can still access—the five miles below the first dam— is in the worst shape of all. “Down there is terrible habitat,” Crain said, “but that’s where the fish are trying to live.”

Because the river water heats up in the reservoirs before it’s released, temperatures downstream are too warm for the salmon; the heat reduces the water’s oxygen stores and spurs the spread of disease. In the early 1990s, for instance, 70 percent of the river’s chinook died before spawning, and the run never fully recovered. Also, because almost all the timber gets caught behind the dams, the lower Elwha has few logjams to create the pools and channels that shelter juvenile fish. In recent years, the tribe has begun constructing artificial logjams.

The worst problem downstream, though, is the lack of usable sediment. Salmon need gravel of a certain size to bury their eggs. Normally, eroded particles from the Olympic Mountains, washed downriver, would replenish the gravel supply, which the Elwha continuously pushes out to sea. But the dams block the sediment from reaching the lower river, where the bottom now is just boulders in places.

The dearth of new sand and gravel also degrades the delta and beaches, which are composed almost entirely of large cobbles now. “We used to have shellfish and clams on our beaches,” Robert Elofson, the tribe’s river restoration director, told me. “Had a geoduck bed out there, but the quality and size of the bed have been impacted. Eelgrass and kelp are impacted too.”

Amazingly, DNA tests have shown that descendants of nearly all the Elwha’s species of wild salmon may still inhabit the river, including chinook and king salmon, coho, pink and chum. The only ones that have likely been eliminated are the native sockeye, which spawned exclusively in a natural lake above the dams. “When the dams went in, their life history trajectory was immediately cut off,” says Mike McHenry, the tribe’s habitat program manager. The other fish still come back to spawn in small numbers, which should grow significantly when the dams are gone. Today only about 200 pink salmon breed in the river, for instance; in the future, park fisheries biologists expect roughly 100,000.

Our propeller plane was now bobbing and dipping in the thick of the mountains. Below us the headwaters of the Elwha frothed white with effort. To get this far on foot entails a grueling three-day backpacking trip; I tried to imagine the willpower necessary to arrive as chinook once did, by water, battling for dozens of miles against rapids and a ripping current.

Suddenly the misty gray ceiling above us lifted, and we were in a cathedral dome of clouds. The pilot mumbled into his mouthpiece and pointed ahead, and I saw a hammock of pure whiteness nestled between mountains. The Snowfinger.

About Abigail Tucker

A frequent contributor to Smithsonian, Abigail Tucker is writing a book about the house cat.

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