Condit Hydroelectric Project is a development on the White Salmon River in the U.S. state of Washington. It was completed in 1913 to provide electrical power for local industry and is listed in the National Register of Historic Places as an engineering and architecture landmark.
PacifiCorp has announced its intention to decommission the project due to rising environmental costs. If approved by FERC, the Condit dam removal will be the largest dam ever removed in the United States, at least until 2012 when the Elwha Ecosystem Restoration Project will remove the Elwha Dam and Glines Canyon Dams on the Olympic Peninsula.
The White Salmon is a glacier fed river originating on the slopes of Mount Adams and emptying into the Columbia River. Condit Dam is about 3.3 miles (5.3 km) upstream of its confluence. The area below the dam is part of the Columbia River Gorge National Scenic Area, while parts of the river upstream belong to the National Wild and Scenic Rivers system. The area is famous for its natural beauty and recreational activities such as whitewater rafting and fishing. Impoundment of the river in 1911 removed 33 miles (53 km) of steelhead habitat and 14 miles (23 km) of salmon habitat.
The Condit Hydroelectric project, named after its lead engineer B.C. Condit, was built by Northwestern Electric Company in 1913 to supply electrical power for the Crown Willamette Paper Company in Camas, Wa. Surplus power was sold to Portland customers via a powerline across the Columbia River. The project was acquired in 1947 by its current owner, PacifiCorp.
The facility consists of Condit Dam and its impoundment, Northwestern Lake; a woodstave pipeline that transports water to a surge tank and auxiliary spillway; two penstocks and the powerhouse. Two horizontally mounted francis turbines and generators produce electrical power, and the exhausted water rejoins the river about a mile (2 km) downstream of the dam.
The original design had fish ladders which where twice destroyed by floods shortly after the dam's completion. The Washington State Fisheries Department then required Northwestern Electric to participate in a fish hatchery instead of rebuilding the fish ladders. This ended natural salmonid migration on the river.
In 1996, the federal government required that PacifiCorp make significant alterations to the dam to meet environmental codes, which included the addition fish ladders. PacifiCorp deemed the modifications too expensive and applied for decommissioning. Currently, the project is operating under annual license extensions, pending approval from FERC of the decommissioning plan. Dam removal is expected to begin in 2008.
When river flow isn't quite enough for two turbines, operation is cycled between running one and both turbines, based on a daily reservoir draw-down and refill cycle. The cycling is timed to meet peak electrical demands; that is, both turbines operate during hours of high electrical demand and the reservoir is drawn down; a single turbine operates during low electrical demand hours while the reservoir refills. A similar cycle is used when inflow is less than enough for a single turbine. A weekly cycle is superimposed on the daily cycle that tends to draw down the reservoir during the week and allowing refill during the weekend. In these cases, known as load factoring, the plant operates as a peaking plant. This mode of operation has been greatly reduced since the 1980s and 1990s to appease lakefront cabin owners.
According to Federal Power Act of 1920, hydropower producers are periodically required to apply for license renewal from FERC. Condit's license was last reviewed in 1991, when it failed approval, and expired in 1993. Since then PacifiCorp has operated the plant under annual license extensions while it seeks approval from FERC for decommissioning.
In December, 2005 PacifiCorp filed an appeal of FERC's 1991 license rejection under the Bush administration's 2005 energy bill, which allows power producers to challenge licensing requirements retroactively. PacifiCorp explains the appeal as a backup plan in case decommissioning falls through.
|Dam type||Gravity dam, long, high|
|Location||Mile 3.3 (km 5.3)|
|Concrete used for construction||30,000 cubic yards (23,000 m³)|
|Floodgates||Five Tainter, two sluice, one hinged crest gate|
|Pipeline||13.5 ft (4.2 m) dia, 5100 ft (1550 m) long, wood stave|
|Penstocks||2 x dia x , steel and wood stave|
|Turbines||2 x Francis|
|Tailrace||concrete lined, 350 ft (110 m)|
|Maximum generating capacity||14.7 MW|
|Maximum turbine hydraulic capacity||1400 ft³/s (40 m³/s)|
|Hydraulic head||167.8 ft (51 m)|
|Operation modes||peaking or baseload, depending on available flow|
|Normal lake maximum elevation above SL||295|
|Reservoir capacity||1,300 acre-feet (1,600,000 m³)|
|Useful reservoir storage capacity||665 acre-feet (820,000 m³)|
|Surface area||92 acres (370,000 m²)|
|Average annual Energy Production (1936 - 1989)||79,700 MWh|
|Annual operating costs||$400,000|
|Annual power benefits||$2,896,000|
|Annual value of power at consumer rates||$4.8 million ($0.06/kWh)|
The investment needed to comply with the new requirements was estimated at $30 to $50 million, while at the same time reducing the amount of water available for power production. PacifiCorp decided the project was no longer economically viable and began negotiations for decommissioning. In 1999 PacifiCorp announced an agreement had been reached, at which point they applied to FERC for approval. The plan called for dam removal to begin in 2006 and capped PacifiCorp's liability at $17.5 million. In 2005 they applied for an operating extension to 2008, to earn another $3.3 million to help offset the cost of dam removal. The main parties involved in negotiations were federal regulatory bodies such as the National Marine Fisheries Service, Native American Tribal governments with interests in the area, and a number of local and national environmental groups.
Breeching the dam involves cutting a 12 x 18 x tunnel in the its base; the final will be drilled and blasted. A dredge will remove woody sediment from the dam's inside face and, when breached, the reservoir will drain within six hours. The rest of the dam will be cut into blocks and removed for disposal or recycling on-site. If decommissioning is approved, Condit dam will be the largest dam ever removed for environmental reasons and the largest dam ever removed in the United States
The quick drainage of the reservoir will flush a large amount of sediment quickly, helping to creating a new river channel above the dam. The remaining sediment will continue to erode until vegetation takes root. The sediment plume will harm the aquatic ecosystem temporarily; in the case of bull trout it will be a negative influence for two years, after which it will be a positive influence due to improved ecosystem nutrition. Also, a new sand bar is expected to form at the mouth of the White Salmon River, interfering with Native American fishing rights, for which PacifiCorp will pay a settlement.
There is opposition to the dam removal from Klickitat and Skamania county governments. Objections revolve around the loss of lake front property and water recreation, loss of wetlands and water habitat, and a perception that PacifiCorp is choosing the cheapest way to abandon the project, rather than paying for FERC's preferred solution (a state of the art fish passage system), which some believe is the best solution for all parties.
The Klickitat Public Utility District Board of Commissioners investigated acquiring the project from Pacificorp to continue its operation as a power plant. A 2002 study commissioned from CH2M Hill calculated that purchasing and upgrading as required by FERC would lead to power production at $64 per MWh, and that for the project to be economically viable it would have to produce power at $45 to $50 per MWh. The report further stated that power produced at Condit would be more expensive than a Gas fired plant for more than 20 years after its acquisition.
In July, 2006, KPUD and Skamania County announced a new effort to acquire the project from Pacificorp and preserve the dam. Their plan relies on trucking spawning salmon around the dam as a less expensive alternative to fish ladders. This type of proposal was previously rejected by FERC. KPUD and Skamania County have retained lawyers and announced their intention to acquire the project under eminent domain should Pacificorp refuse to negotiate a sale.
Most environmental groups involved with the decommissioning plan, as well as the national forest service, believe that the long term benefits of removing the dam far outweigh the short term damage done by flushed sedimentation. And fish and environmental advocates see this case as an important precedent for dam removals to restore free flowing rivers.