The ecology of dams and dam removal: Condit Dam on the Lower Salmon River, WA (Part 3)

The White Salmon River watershed and surrounding vicinity. Borrowed from friendsofthewhitesalmon.org

By Nate Hough-Snee

Near Washington State’s Mt. Adams, a small river begins, flowing south into the Pacific Northwest’s largest wild Salmon production facility, the Columbia River. This river begins in steep headwaters on one of the Pacific Northwest’s lesser volcanoes and runs 44 miles through forests ranging from the subalpine to second-growth plantations, draining roughly 400 square miles. This relatively short, but spectacularly beautiful river is the White Salmon. More than half of the river was designated as either wild or scenic by congress in 1986. Not surprisingly, the river has been popular with boaters, hikers and photographers for the last century, partially due to its access to world-class whitewater, and partly because of the sublime setting of the upper watershed.

White Salmon River. Photo copyright Gary Grossman.

In startling contrast to the congressionally-ordained beauty of the upper White Salmon, a century-old concrete behemoth once resided a mere 3.3 miles upstream of the Columbia River-White Salmon confluence. This behemoth, the Condit Dam, like those dams formerly impounding the Rogue River, blocked salmon migration, prevented the movement of sediment and gravel across the watershed, and for at least a moment in time, provided great economic benefits to the local community. The trade-off was for years massive – the residents of Skamania and Klickitat counties received cheap power while migrating salmon were left with less than 10% of their historic range on the river, and next to none of it spawning habitat.

Condit Dam and Penstock. Photo from historichoodriver.com

While the Savage Rapids Dam on Oregon’s Rogue River existed to store water for the economical production of alfalfa and cows, the Condit Dam existed to provide cheap electrical power to local communities. At the PacifiCorp-owned dam, two large penstocks diverted water nearly a mile downstream, using 170 feet of head to turn two Francis turbines. The Condit Dam chugged along from 1913 onward, creating 79,700 Megawatt hours of electricity at $0.06/kWh), with almost nobody except the public utility districts and PacifiCorp taking note.

It has been overheard at many an event within the Pacific Northwest that, “cheap hydropower is what makes the Northwest economy mightier than Appalachia.” Like the Savage River Dams’ water storage, the cheapness of this hydroelectricity is laced with externalities: the loss of fisheries, downstream sediment delivery, and in many case, the way of life that accompanied Columbia River Basin salmon runs. By 1991 these publicly-born externalities became clear enough that the paradigm of cheap power on the White Salmon received a swift kick to the groin. In 1991, the Condit Dam applied for relicensing, and at the time the Federal Energy Regulatory Commission (FERC) stepped in to mandate what NOAA’s National Marine Fisheries Service would have eventually sued for: fish passage upstream. The application for relicensing failed based on the absence of fish ladders, long gone from floods that occurred shortly after dam construction. For nearly two decades, the Condit Dam would operate conditionally under annual license renewals while working with the FERC to find a viable fish passage solution for the dam.

Condit Dam powerhouse circa 1932. Photo by James Woosley

FERC was asking PacifiCorp to reduce the water that would be allocated to power production, while also installing a multi-million dollar fish ladder system. It was estimated that the ladders would cost several million dollars. This would be a big hit to PacifiCorp, but a hit that the dam may have been able to survive with continued power production and rate hikes. With the loss of power production at base flows, the project would have been substantially more expensive for PacifiCorp. The FERC politely and firmly entered into a staring contest with PacificCorp. After a decade, viable alternatives to expensive fish ladders failed to materialize and in 1999 the dam’s decommissioning was approved. After nearly a century, the White Salmon would run freely back to the Columbia.

If removing the dam for economic reasons was perceived to be risky for PacifiCorp, their first act in removing the dam would be an ecological spin of the roulette wheel. Many dams are removed in stages with parallel dredging of sediments, controlled reservoir drawdowns and concerted, methodical replanting and sediment management. Parting with tradition, PacifiCorp decided to blow the dam in one fell swoop, pulse the sediment downstream and start over. No silt lingering as spawning fish tried to return, no expensive sediment removal, and no big equipment on barges. If the Elwha and Glines Canyon Dams are dying a slow, painful death, in dam removal terms, the Condit Dam went to the doctor on a Monday and was diagnosed as terminally ill on Tuesday. The Condit Dam was dead by Friday. On October 26th, 2011 (actually a Wednesday), the Condit Dam was blown up, moving 750 acre-feet of water downstream, sediment and all. Stakeholders agreed that the long-term solution to acutely remove the dam that impaired fish was a much better trade-off than trying to mitigate for the dam’s take of migrating fish.

The ecological and geomorphic changes that have occurred within the river following dam removal are currently being documented by federal, state and tribal entities. The initial monitoring following dam removal focused on the fate of the sediment plume, but moving forward, will shift to estimating habitat quality and fish population dynamics.

The Condit Dam, unlike the Savage Rapids Dam has received considerable attention from the public. http://whitesalmontimelapse.wordpress.com/ provides an impeccable history of the dam and it’s creation, the resulting changes to the watershed and fishery and finally dam removal. Andy Maser and Steve Sampfli have done a knock-out job documenting this project, and their work will tell a thorough and elegant story of the White Salmon, Condit Dam and hopefully the ensuing ecosystem recovery. The videos linked below are theirs. For more technical details, PacifiCorp has publicly archived their decommissioning reports, photos and FERC documents, while the Washington State Department of Ecology also has an excellent website on ecosystem recovery in the White Salmon.

Condit Dam Removal Explained from Andy Maser on Vimeo.

Explosive Breach of Condit Dam from Andy Maser on Vimeo.

Up next: Part 4 – the Elwha and Glines Canyon Dams on the Elwha River and Part 5 – synthesis.

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