Out on the Olympic Peninsula of Washington state something incredible is happening. A major river has been deliberately set free. Persistent public interest and action, using the rule of law, prevailed in taking down two dams that have been strangling the Elwha River for the past century.
I cross the Elwha every time I go out to the open coast. Over the past few years I’ve been stopping to see how it’s been changing as the dams have come down. Join me on a trip down the river in pictures, with a brief description of what’s happening.
First, some context.
The river:
The Elwha is one of a dozen big rivers draining tremendous rainfall and snowmelt pouring off the peaks and hillsides of the Olympic Mountains. This small range rises 8000 feet almost straight up from the sea, catching moisture carried onto the continent by prevailing westerlies. Most of the rivers flow into the Pacific Ocean (like the Hoh and the Quillayute) or Hood Canal (like the Dosewallips); the Elwha is one of the few emptying northward into the Strait of Juan de Fuca. Like most Olympic peninsula rivers it is relatively short — its mainstem 45 miles — but it carries a huge load of runoff through a variety of habitats. Most of the river’s watershed (89%) is within Olympic National Park, and is largely wilderness. Before the dams went in the Elwha was notable for hosting all five species of Pacific salmon as well as several kinds of trout, and its terrestrial ecosystem diversity was equally rich.
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The dams:
In the early 20th century entrepreneurs arrived on the peninsula looking for ways to exploit the lush resources there. Thomas Aldwell saw potential in damming the Elwha to generate profitable electricity to power the lumber and paper mills in nearby Port Angeles. He bought up land along the river, formed a company and constructed first the Elwha dam (completed in 1913) and then the Glines Canyon dam further upriver (completed in 1926).
The effects:
Even though Aldwell was required to include fish ladders by an 1890 Washington state law, he cut a deal with the current State Fish commissioner,
agreeing to build a fish hatchery instead. The hatchery came to nothing, and the ~400,000 salmon who’d been migrating up the river for eons were trapped at 5 miles, unable to access the 70 miles of upriver and tributary habitats. 98% of the salmon disappeared from the Elwha. The loss of spawning salmon had a cascade effect, depriving upriver ecosystems of food for predators and scavengers, and eliminating the transfer of nutrients up into the forest.
As the dams pooled the river into lakes the temperature of the water rose making it unsuitable for many fish and promoting disease and parasites. Sediment also began to collect in the lakes depriving the river bed down-river and even along the coast. Instead of spreading varied sizes of sediment onto the riverbed, the river eroded it instead leaving a barren rocky riverbed rather than a productive one. The absence of sediment flowing out into the Strait also deprived shorelines to the east, including Klallam Tribe lands and Ediz Hook (a long sandspit protecting Port Angeles harbor, artificially and expensively reinforced by the Army Corps of Engineers for the past few decades).
The dams come down:
Ever since the dams bottled up the river, the local Native American tribex pressed for removing them. Salmon have always been essential to the Lower Elwha Klallam Tribe, for food and other reasons. When the
Boldt decision was handed down in 1979 returning treaty fishing rights to Indians, the Klallam had standing to request a return of the lost Elwha salmon runs. The legal fight began in earnest after Crown Zellerbach, then owner of the dams, applied to the Federal Energy Regulatory Commission to re-license The Glines Canyon dam. The Klallam Tribe and several environmental groups argued that dams are inappropriate inside a National Park (ONP established in 1938) and catastrophic to wildlife. The debate was taken up in Congress where Senators Brock Adams (D-Wash) supported dam removal and Slade Gorton (R-Wash) argued against it. Ultimately in
1992, the Elwha River Ecosystem and Fisheries Restoration Act came into law. The Federal government would buy the dams, take them down and restore the river ecosystems and fish runs. It took another 20 years of obstruction, and then planning, before dam removal actually began.
While 1000 dams have been removed in the last century (mostly in the last couple of decades; see this interactive
map for those near you) out of the 100,000 or so on U.S. waters, this project was the biggest yet attempted. Most dams are small. The Glines Canyon dam was 210 feet high, wedged between bedrock walls. After seeing the catastrophic effects of the “blow and go” technique on other projects, engineers decided to take the dams down gradually so the accumulated sediment wouldn’t devastate downriver habitats with a wall of mud.
One of the goals of the Elwha restoration project is to revegetate the newly exposed riverbanks. Left to itself, plants would colonize spontaneously but to avoid invasive weeds, which reproduce faster and more prolifically than native plants, an active approach has been implemented.
Total restoration activities in the Lake Mills and Lake Aldwell areas will take seven years and crews will install a variety of native plant species in different forms from seed to bare root. Planting within the former reservoir areas started in 2011 and will continue through 2017. Over the project period over 400,000 seedlings, trees and live stakes will be planted. In addition 2,000 pounds of seed will be applied to the Lake Mills restoration project area (Chenoweth et. al. 2011). — ELWHA RIVER REVEGETATION 2013: A PLANT PERFORMANCE STUDY
Two historical photos to compare to the current state of the old dam site:
This is what it looks like today. The near bank has been re-engineered to prevent erosion. There’s a black and white circular marker affixed near the top — perhaps a way to monitor the stability of the reformed bank? (sharp eyes may spot an eagle perched in a tree on the right).
Where the river empties into the Strait, there have been big changes. This sequence of photos below is from the USGS. The old river mouth had a narrow beach and eroded banks. During the flushing of sediment, even implemented slowly, a gigantic plume spread out into the sea, temporarily darkening nearshore habitats and killing kelp. The sediment also overwhelmed the new treatment plants built to purify drinking water for Port Angeles. Now there’s less sediment washing down, and it’s dropping gradually, re-creating a delta as it used to be before the dams went in.
I walked out onto the delta a few weeks ago. There were quite a few other people there too. The Elwha dam removal and restoration project is of great interest not just to the Park Service and science researchers, but to the general public in the Northwest, many of whom participated in the dam-removal fight.
The Lower Elwha Klallam reservation is on the other side of the river. New sediment has been rebuilding eroded shoreline there.
And the salmon?
Recovering the salmon populations has been a high priority of the restoration project since the start. Reports say salmon are already swimming up past the old dam sites in the free-running river and field researchers have counted many redds — yay! (see the details at the NPS site). However there’s some heated controversy about how to best re-establish the runs. Should it be wild salmon or hatchery fish? The Elwha salmon recovery is an issue that deserves its own article.
oooOOOooo
As alway, all nature observations are welcome in the comments below. Tell us what you’re seeing in your own natural neighborhood.
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