Crews chip away at Condit Dam
Dismantling of dam on White Salmon River moves toward target of Aug. 31
Wednesday, July 11, 2012
WHITE SALMON — The numbers are impressive: 500 cubic yards of concrete hauled out each day. Six days per week. Workers at it 12 hours a day.
As the dismantling of Condit Dam continues, piece by piece, crews have picked up speed since the removal process began in earnest earlier this year. They'll have to keep it up if they hope to have it gone by an Aug. 31 target that's looming ever closer. PacifiCorp project coordinator Todd Olson estimated workers still have more than halfway to go with the structure itself.
"It's going to be tight," Olson said.
It's been more than eight months since a blast of dynamite breached Condit Dam in October, releasing the White Salmon River to flow freely for the first time in nearly a century. Northwestern Lake drained in barely an hour, and a deep canyon of mud emerged as the river carved its new course. That's now given way to steep, rocky river banks in places near the dam. But it's clear the landscape isn't done evolving.
PacifiCorp, which owns the dam and the area surrounding it, now has its eye toward helping the area find its new natural state. The Portland-based utility has graded much of the land that used to be inundated by Northwestern Lake, hoping to stabilize it and reduce unwanted erosion. Tree stumps dot otherwise bare slopes, offering a glimpse of what was. Crews will replant the area with natural vegetation later this year, Olson said. Then, they'll get out of the way.
"Our hope is that Mother Nature just does its thing,"
Olson said. "No one really knows how long that's going to take."
Once the dam is gone for good, rafters could ride the White Salmon River all the way down to its mouth at the Columbia River as soon as this fall. Many are already using a rebuilt take-out ramp at Northwestern Lake Park, a few miles upstream of Condit Dam. On Wednesday afternoon, a group of six large rafts with nearby white-water outfitter Wet Planet came off the water.
Condit Dam is gradually disappearing, and crews have made good progress in recent weeks, Olson said. As crews under lead contractor JR Merit chip away at what was a 125-foot-tall structure, each day it gets shorter -- exposing the wider base -- allowing more machinery to work atop the dam at one time. Dump trucks bring loads of concrete out to be spread along the former flow line that once carried water from the dam to the powerhouse farther downstream.
PacifiCorp decided to decommission the hydroelectric dam last year rather than install costly fish passage upgrades. But the removal process hasn't come without bumps of its own.
The final price tag is expected to reach $37 million, Olson said, about $5 million more than initial estimates. Costs rose as PacifiCorp worked to stabilize the bridge over the river at Northwestern Lake Park after the reservoir drained, he said. A dispute with cabin owners over dried-up wells has added to it. And PacifiCorp last month bought out one cabin considered unstable due to the river's shifting banks, Olson said, and plans to demolish it. Two other cabins are also off-limits due to similar safety concerns, and PacifiCorp is in negotiations with those owners, Olson said.
Uncertain fish future
One big question mark surrounding the Condit Dam removal is how fish will respond to the free-flowing river. A proposed management plan from the National Fisheries Marine Service would take a mostly hands-off approach at first.
"The hope is that we get some recovery, some natural production," said Rich Turner, a fisheries biologist with the National Oceanic and Atmospheric Administration who was involved in the plan.
Wildlife officials placed fall chinook salmon above the dam before its breaching last year. So far, no other fish have been confirmed on the river, Olson said.
The White Salmon River presents a unique opportunity, according to Turner. It's not often a century-old dam is breached, and other examples often leave the structure in place. Removing it completely removes some passage problems, he said.
One comparable example is the Elwha Dam on the Olympic Peninsula. The structure was dismantled earlier this year, but scientists have reportedly already spotted wild steelhead in a tributary of the Elwha River, past the former dam site.
On the White Salmon, Olson expects conditions to be much quieter late this year, when Condit Dam is gone and the area is replanted. They'll also keep invasive species in mind, he said, hoping to avoid leaving it "a dust bowl and a weed patch."
"We've got a ways to go," Olson said. "But we've certainly made some good progress since the breach time."