Some say the removal of Washington’s Condit Dam is a sign of what’s to come on the Klamath River
by JOEL ASCHBRENNER, Herald and News 11/15/11
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| AP photo courtesy of PacifiCorp A hole is breached in the 100-year-old Condit Dam on the White Salmon River Oct. 26 near White Salmon, Wash. The 12-story dam is one of the largest dams to be breached for fish passage in U.S. history. |
A cloud of brown, sediment-laden water exploded from the bottom of the Condit Dam following the final blast to breach the nearly 100-year-old dam.
The murky water gushed from a 13-foot-by-18-foot hole in the dam last month, flowing to the Columbia River less than three miles downstream. Above the dam, the 92-acre Northwestern Lake drained in less than an hour — five to six times quicker than predicted — leaving a mudflat where the river carved a steep canyon into the silt and sent iceberg-like chunks of sediment f loating downstream.
Breaching the PacifiCorp dam on south central Washington’s White Salmon River is one of the first steps in returning the river to its natural flow, but it is the culmination of 20 years of studies, permitting and settlement talks.
Condit is one of the largest dams breached for fish passage in U.S. history. Some say it will serve as a litmus test for the plan to remove four PacifiCorp dams on the Klamath River.
PacifiCorp officials, however, say the success or failure of the Condit Dam removal will have little bearing on the Klamath River.
The huge amounts of sediment left behind the Condit Dam show how problematic dam removal can be, said Tom Mallams, president of the Off-Project Water Users Association and a vocal opponent of K la mat h River dam removal.
“I’m hoping people look at the results and don’t believe the rhetoric that comes out of the environmental groups,” he said. “ They say the river is clean and running free now, but it’s not running free. It’s a little trickle through a mudball, which is nothing desirable if you ask me.”
Craig Tucker, spokesman for the Karuk Tribe, which supports Klamath River dam removal, said the Condit Dam could provide insight in how dam removal affects river ecology. It’s too early, however, to draw any conclusions from the Condit Dam, he said.
“If you look at those pictures of Condit now, it doesn’t look too attractive — there’s a lot of mud and silt,” Tucker said. “But we have to look back in one, three, maybe five years, at the overall health of the river.”
PacifiCorp spokesman Tom Gaunt said sediment is being washed down the White Salmon River as expected and the company has contingency plans to remove excess silt if too much remains. Dam removal on the White Salmon River, Gaunt said, hardly compares to dam removal on the Klamath River.
“They are two very different rivers,” he said. “Klamath is its own issue and it encompasses an even wider range of issues than at Condit.”
Proposal to remove Klamath dams comes about in familiar way
A plan to remove four hydroelectric dams on the Klamath River is coming together similar to a removal plan for the Condit Dam on Washington’s White Salmon River.
PacifiCorp first considered removing the Condit Dam in 1991, said PacifiCorp spokesman Bob Gravely. The dam’s federal license expired in 1996 and relicensing would have required adding fish ladders and screens and increasing in-stream flows. Doing so would make operating the dam uneconomical, PacifiCorp officials say.
So PacifiCorp joined 22 other parties to sign a water settlement deal in 1999 calling for the removal of Condit and restoration of fish habitat there.
On the Klamath River, the four dams proposed for removal have licenses that expired in 2006. PacifiCorp was faced with a similar mandate to install fish ladders and screens. Adding fish ladders would cost millions more than removing the dams and would reduce their power potential by about 25 percent, so the company began closeddoor water settlement talks with Klamath Basin stakeholders.
Those talks spurred the Klamath Basin Restoration Agreement and Klamath Hydroelectric Settlement Agreement, which were signed in 2010. The Secretary of the Interior is expected to determine in March if dam removal is feasible and in the public interest. Pending that determination and legislation to fund the agreements, the dams would be removed in 2020.
PacifiCorp officials, however, say removing dams rather than relicensing is not company policy. PacifiCorp recently began installing fish ladders in Washington at its Lewis River dams as part of requirements to relicense the 510-megawatt hydroelectric project there, Gravely said.
Condit project smaller than Klamath plan
The Condit Dam is the largest hydroelectric facility PacifiCorp has ever removed, said company spokesman Bob Gravely, but the project is only a fraction of the scale of proposed dam removal on the Klamath River.
The 125-foot high, 471-foot long Condit Dam produced up to 13.7 megawatts of power, enough to power about 7,000 homes. Removing the dam cost an estimated $33 million.
The four Klamath River dams proposed for removal — the J.C. Boyle, Copco No. 1 and No. 2 and Iron Gate — can produce up to 169 megawatts, enough to power about 70,000 homes, PacifiCorp officials say. Removing them will cost between $247 million and $290 million.
There was an estimated 2.3 million cubic yards of sediment behind the Condit Dam. Behind the four Klamath River dams sits an estimated 13.4 million to 16.5 million cubic yards of silt, with nearly 9 million cubic yards behind Copco No. 1 alone, according to a Department of the Interior environmental impact study released in September.
Dams being removed from Elwha River
Hydroelectric dams also are being removed on the Elwha River, one of the largest rivers in Washington’s Olympic Peninsula.
Removing the Glines Canyon Dam and the Elwha Dam there is expected to take three years and cost nearly $27 million. It’s the largest dam removal project in U.S. history, according to the Department of the Interior. Construction work to remove both dams began in September. At the 210-foot-tall Glines Canyon Dam, sections of concrete will be removed one-by-one. This “notching” process will slowly drain the reservoir over time.
A temporary diversion channel will be dug around the Elwha Dam, allowing the reservoir to drain while the 105-foot-tall concrete dam is deconstructed.
The Elwha and Glines Canyon dams, built in 1913 and 1927, respectively, generated electricity for a nearby paper mill for decades. In 2000, the Department of the Interior bought the dams in order to remove them. Removing the dams will allow anadromous fish to reclaim 70 miles of spawning habitat blocked by the dams, according to the Department of the Interior.
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