04 November 2011

Free at last

For 98 years, the 125-foot high Condit Dam in southeastern Washington State held back the White Salmon River, creating a serene lake, but choking off the waterway to salmon. Wednesday, in an historic effort, the dam was dramatically breached, and ecologists hope the increased flow of water will restore the waterway to fish and other aquatic organisms, as well as the birds and mammals that rely on them...

According to news reports, Portland-based PacifiCorp had decided that it was cheaper to source the dam's 14 megawatts elsewhere, rather than install expensive fish ladders and other improvements on the site, as would have been required for relicensing. According to the AP, the dam removal cost around $32 million, while the improvements would have cost $100 million...

Before the dam was demolished, biologists relocated salmon that were spawning below the structure, so their nests wouldn't be covered with silt.
Additional information at the National Geographic source, via The Presurfer and Neatorama.

7 comments:

  1. so much for 'clean' electricity, eh?

    It's always interesting the tradeoffs we have to make.

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  2. That surge looks very destructive. My first thought was that it could have been released more gently, but then I suppose the flow wouldn't have carried the silt properly. And anyway, sudden surges like that presumably happen as a result of natural events from time to time anyway.

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  3. Skipweasel, I think in the Grand Canyon the hydraulic engineers generate sudden releases like that to deposit sand/silt on the riverbanks to enhance various habitats.

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  4. As a Washingtonian, I'm very much in favor of hydroelectric power. Sadly many of our older dams were built without much of an understanding of their impact on the local biosphere. It's hard to weigh the natural impact against the electricity produced and sure to leave sore feelings no matter what's decided. The dams themselves are fascinating structures, though, thanks for bringing this one to our attention.

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  5. The electricity production being lost with this is being made up for by newer wind farms as well as hydro from more modern dams nearby. (hooray clean energy!) All the people I talked to local to this reservoir were in support of the dam being removed, which I think says a lot.
    We NW'ers love our salmon, and restoring the original flow and terrain as well as allowing the salmon to finish their drive upstream unimpeded more than makes up for some cloudy water for the next few months. I think PacifiCorp's decision in this case was a sort of a win-win.
    The dam itself is going to be removed over the next ten months, I can't wait to see how it looks a year from now-

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  6. Spectacular video!

    It's amazing how silted up the reservoir got. I've heard this kind of silt makes great garden soil as long as its not too polluted.

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