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| the problem |
The Northwest's worst kept secret is the decline of salmon populations in its rivers and streams. Nevertheless salmon culture has persisted down the ages into the 21st century. How to save the salmon from extinction in the wild is a perennial debating topic contested by interests with conflicting goals. When dams were first constructed for irrigation and later power on the region's waterways, fish ladders were required to allow salmon to spawn upstream. But ladders proved repulsive to salmon, so they gave way to hatcheries. Hatcheries have also proved to be a poor solution as wild populations have continued to decline. Biologists note hatchery raised salmon to be less robust, an observation seconded by sport fishers. Hatchery fish are also suspected of spreading disease to wild stocks. Now,
when all else has produced disappointing results, Northwestern states are turing to what was perhaps an obvious, from a biological standpoint, but unprofitable solution--dam removal.
US Person advocated for this action with Oregon's former Republican Senator Gordon Smith in Washington, DC.
Oregon has removed several smaller water control dams recently but the dam removal project on the Elwah River in Washington state's Olympic Peninsula is certainly the largest, and one of the most ecologically ambitious ecological restoration projects in the Northwest. Demolition of two dams blocking salmon runs began in 2011 and is now nearing completion. Before the dams were built, the Elwha River hosted all five of the Northwest's Pacific salmon species: sockeye, coho, chum, pink, and chinook. Elwha's chinooks were monsters, commonly reaching 100 pounds. The runs of the various species took place a different times all year, so the river was full of migrating salmon, perhaps 400,000 annually. Soon the salmon stopped returning to their ancestral river because the Elwah dam without a ladder blocked their run. By 1990's the native sockeye were extinct, and the chinook and chum nearly so. The dams also deprived the Klallam tribe of a major food source and cultural icon. The benefit for all of this habitat destruction was power for a single Port Angeles paper mill.
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| a solution |
After their fishing rights were restored in the 70's the tribe fought a protracted legal battle with the aid of conservation groups to remove the Elwah River dams. After a heated political battle, Congress authorized the Interior Department to buy the dams for $29.5 million and remove them if necessary. Destroying the structures is just part of a complicated effort to re-create an entire watershed that has been altered by unnatural impoundments of large amounts of water. Sediment has built up over more than a century. Getting it moved downstream and out into the Strait of Juan de Fuca has been problematic. The upper dam, Gilnes Canyon
[photo], had to be removed slowly in stages to allow an estimated 34 million cubic yards of sediment to be moved downstream by the river, and also to allow remaining salmon opportunities to spawn without choking on the silt, sand and gravel. 700 acres of forest has to be replanted with native species in a nutrient poor lake bed. Fish repopulation relies on hatchery fish, a method conservationists are suing to stop since they think it threatens endangered wild fish. Hatchery fish are transported around the lower reaches of the river to clearer channels above the former lower Elwah dam. About half of these have spawned successfully. In 2012 500 wild fish churned up the Elwah and natural gravel bars are re-forming, a good sign that the river is on the road to a full recovery. Most the Elwah watershed is protected in Olympic National Park. But whether the Elwah success story will be enough to convince policy makers to remove the big dams on the upper Columbia River and Idaho's Rogue River that block more than a third of the salmon's former spawning grounds is a policy question yet unanswered and sure to be controversial.
