October 27, 2011
Condit Dam Demolished, White Salmon River Flows Free For 1st Time in Nearly a Century
By Chad Love
An almost century-old dam that blocked crucial spawning waters for Pacific northwest salmon and steelhead came crashing down yesterday.
From this story in the Seattle Times:
With a massive charge of TNT detonated at the base of Condit Dam, the White Salmon River roared back to life Wednesday. Penned up and drowned under a reservoir since the 125-foot-tall dam was completed in 1913, the White Salmon quickly found its natural channel.
Engineers had predicted it could take up to six hours to drain Northwestern Lake, which covered 92 acres and stretched 1.8 miles upstream. But the river was free flowing within two hours of blasting through a drain tunnel at the base of the dam at 12:11 p.m. Thomas Hickey, senior hydro engineer for PacifiCorp, said all went as planned in the breach. And while the river was a muddy mess, sluicing out some of the 2.4 million cubic yards of sediment behind the dam, scientists had expected that to occur. They planned ahead, salvaging 679 adult tule fall chinook from below the dam last month, and carrying the fish above the dam to spawn.
"...Located three miles from the river's confluence with the Columbia, taking out the dam is expected to reopen about 33 miles of habitat for steelhead and about 14 miles for chinook, depending on how well different runs of fish contend with natural falls in the river.