Tuesday, November 1, 2011

Release the River: Condit Dam Removal

The biggest dam removal project in Washington history had a spectacular start this last weekend. Condit Dam built in 1913 had a tunnel blasted through its base with the final blast this past week. The lake behind the hole drained down in a couple of hours. The dam removal came after nearly a 20 year process to get to this point. When Pacific Power applied to relicense the dam in 1991, the Federal Energy Regulatory Commissioner (FERC) provided as conditions for renewal a new fish passage structure and operation of the dam in a manner that was less harmful to fish. The fish passage structure was very expensive and the new operational requirements limited the electric generation that made the dam less profitable. After years of operating with an annual license Pacific Power opted for removing the dam.

However, there was further wrangling over the dam. Skamania and Klickitat Counties sought taking control of the dam but in the end they too decided it was not feasible. The next struggle was just how was the dam to be removed. There was a lot of sediment built up behind the dam. FERC wanted the sediment dredged; however, Pacific Corp argued against the high cost and presented the approach that while the impacts of a sudden breach might be harmful, the period of damage would be short lived. In the end Pacific Power prevailed with sudden breach approach. And I will say that it makes for good video as well as interesting geology processes.

Two videos: first is some great footage of the breach, flooding and erosion assembled by Columbia River Keeper and the second an overview of the project by Pacific Power. The term "release the river" is a quote of Treebeard in Lord of the Rings.


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