Monday, October 12, 2009

Damn Dam

Rogue River in Oregon

The environment and our need for energy as long been at odds. And for as long as mills have ground grain into flour or hewn logs into lumber, our waterways have served our power needs. In more recent times, we have damned damed our rivers, rushing waters spinnign turbines, to create direct electricity. No viable form of energy production is without its impacts. Overly channelized rivers have destroyed the landscape's ability to deal with flooding, habitats were destroyed by the dam lakes, and some species such as salmon have neared depletion as spawning waters were cut off from the ocean.

The environmental impact can and has been mitigated by some projects like fish ladders. However, there is a growing trend to return some damed rivers to their (more) natural state by removing or altering the dams. Frequently, this is not possible in areas where development has occurred downstream. On the Rogue River in Oregon, the natural area surrounding the aged Savage Rapids Dam allowed for its recent demolition. For the first time in more than 100 years, the Rogue could flow unimpeded for 157 miles from the Cascade foothills to the Pacific Ocean. The dam's fish ladders, as well as some fish screens, no longer meet federal standards. The U.S. Bureau of Reclamation thinks removing the dam will increase the number of salmon reaching spawning grounds by 22 percent a year, an increase of about 114,000 fish.

Construction crews built a coffer dam and started jackhammering half of the dam to pieces last April, and on Friday removed the piles of rock and gravel holding the river back, allowing the river to flow freely. The rest of the dam is to be removed by December. The river quickly cut down through the huge accumulation of sand, gravel and rocks that had built up behind the dam the past 88 years. A flotilla of some 80 people in rafts, driftboats and kayaks celebrated the breaching of the Savage Rapids Dam this past Saturday by floating through the remains of the concrete structure. "What this really represents today is our culture being capable of backing up a little bit and doing something differently," said a flotilla participant as he pushed off from the bank and rowed his driftboat down the newly freed section of river.

Source: Jeff Barnyard, AP

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