If you love the demolition of tons and tons of concrete, then fix your gaze on Washington state. Sure, you’ve read—and if you haven’t yet, check my blog here—all about Viadoom and the destruction of Seattle’s aging Alaskan Way Viaduct. But that’s just a small sampling of the crashing of concrete around the state, a state that has the removal of the nation’s three tallest dams to ever come down in history concurrently ongoing.
Yeah, right now, three roughly 100-year-old dams are getting ripped out of Washington rivers. And they’re all super huge. Again, highly publicized was the beginning of demolition on the Elwha River and Glines Canyon dams in September—read my blog about it here (don’t you love the shameless self-promotion). But just last week work started on pulling out the Condit Dam too. Crews in south central Washington started it out with a blast, just to make things a bit more interesting.
Crews pounded a hole in the 125-foot-tall dam in the White Salmon River using plenty of detonation prowess, sending the pent up 92-acre reservoir of Northwestern Lake downstream in a mere two hours, four hours faster than the conservative estimates had predicted.
The Condit Dam (finished in 1913) removal will go quite differently than the gingerly deconstructed Elwha and Glines Canyon projects. Both of those dams, located on the Elwha River in the Olympic National Park, are being slowly dismantled from the top down. The Elwha Dam (finished in 1913), actually the third-highest of the trio at a mere 108 feet tall, and the Glines Canyon Dam (1927), the tallest at 210 feet, have crews actively removing just a few feet of concrete at a time to slowly trickling the sediment into an environmentally sensitive area. Things run a bit differently on the White Salmon River just three miles north of its confluence with the massive Columbia River.
There, a blast in the bottom of the 125-foot-tall structure released the river in a torrent of water and the Northwest’s winter rains should wash the remainder of the backed-up sediment out of the area. And instead of slow-moving deconstruction, crews will return to the area in spring 2012 and have the entire structure torn out by the end of the summer 2012, opening 33 miles of new spawning and rearing grounds for steelhead and 15 miles for salmon.
In the end, the removal of all three dams aims to restore natural habitat to the area without a drastic reduction in power provided to the area. After all, the 100-year-old dams weren’t the top-producing pieces in the Northwest’s hydropower portfolio. So, for the next three years—like I said, it will take longer over at the Elwha River—folks can watch the dismantling of concrete dams throughout Washington State. And when that all wraps up, turn your attention back to the Alaskan Way Viaduct and its eventual complete demolition. The concrete keeps crashing in the Pacific Northwest.
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