THE FEDERAL ENERGY Regulatory Commission (FERC) has released a staff report endorsing the removal of the 38.1m high Condit dam on the White Salmon river in Washington, US. However, the state of Washington Department of Ecology is conducting public hearings on how water quality would be affected if the dam is removed under what is known as 401 certification.
The dam’s owner, Portland-based PacifiCorp, has sought permission from state and federal agencies to remove the 89-year-old structure rather than relicense the dam for hydro generation, under conditions stipulated by FERC, with fish passage structures for salmon and steelhead. If the utility wins approval from the state regulators, PacifiCorp will blast a hole in the dam, releasing more than 1.5Mm3 of sediment trapped upstream of the dam in the process. The sediment will wash into the river’s lower 5.1km, filling deep pools near the mouth of the river that are used by salmon and steelhead and could permanently raise the river’s level by 3m.
The work would be performed in October 2006. In its 1999 settlement agreement with environmental groups, public agencies and Columbia river tribes, PacifiCorp capped its costs for dam removal at US$17.15M.