Condit Hydroelectric Project
Encyclopedia
Condit Hydroelectric Project was 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
decommissioned the project due to rising environmental costs, and the dam was intentionally breached
on October 26, 2011. Condit Dam is the largest dam ever removed in the United States, although its record is not slated to outlast 2012.
-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 the 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 power line across the Columbia River
. The project was acquired in 1947 by its current owner, PacifiCorp
.
The facility consisted of Condit Dam 45°46′02"N 121°32′16"W in Klickitat County, and its impoundment, Northwestern Lake; a woodstave
pipeline that transports water to a surge tank
and auxiliary spillway
; two penstock
s and the powerhouse. Two horizontally mounted francis turbine
s and generators produced electrical power, and the exhausted water rejoined the river about a mile (2 km) downstream of the dam.
The original design had fish ladder
s which were 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 ordered PacifiCorp to alter the dam and add fish ladders to meet environmental codes. PacifiCorp deemed the modifications too expensive and asked to decommission the dam instead. The project operated under annual license extensions until the Federal Energy Regulatory Commission
(FERC) approved decommissioning. The dam was breached at noon (Pacific Time) on October 26, 2011.
At the time, it was the largest U.S. dam to be removed. In 2012, the Elwha Ecosystem Restoration
Project on the Olympic Peninsula
is slated to remove the larger Elwha Dam
and Glines Canyon Dam
s.
for electrical power generation and returned to the river about a mile downstream. Additional flow beyond what the turbines could use was discharged through five tainter gate
s and two sluice gates. The dam crest had a pneumatically actuated hinged crestgate
which was designed to fail catastrophically as a safety relief when flow exceeds 18000 ft³/s (510 m³/s). The river averages 1125 ft³/s (32 m³/s), with flows up to 3500 ft³/s (99 m³/s) fairly common.
When river flow wasn't quite enough for two turbines, operation was cycled between running one and both turbines, based on a daily reservoir draw-down and refill cycle. The cycling was timed to meet peak electrical demands. That is, both turbines operated during hours of high electrical demand and the reservoir was drawn down. A single turbine operated during low electrical demand hours while the reservoir refilled. A similar cycle was used when inflow was less than enough for a single turbine. A weekly cycle was superimposed on the daily cycle that tended to draw down the reservoir during the week and allowed it refill during the weekend. In these cases, known as load factoring, the plant operated as a peaking plant. This mode of operation was greatly reduced through the 1980s and 1990s to appease lakefront cabin owners.
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 explained the appeal as a backup plan in case decommissioning application failed.
requirements. FERC's report also reviewed options to decommissioning the project, which it estimated would cost twice as much as the fish passage system.
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.
Breaching the dam involved cutting a 12 x 18 x 100 feet (30.5 m) tunnel in the its base; the final 15 feet (4.6 m) was drilled and blasted. A dredge removed woody sediment from the dam's inside face and, when breached, the reservoir was expected to drain within six hours, but actually drained much faster. The rest of the dam will be cut into blocks and removed for disposal or recycling on-site. As of the date of demolition, Condit dam was the largest dam ever removed for environmental reasons and the largest dam ever removed in the United States.
The quick drainage of the reservoir flushed a large amount of sediment quickly, helping to create 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.
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 have led to power production at $64 per MWh, and that for the project to be economically viable it would have to have produced power at $45 to $50 per MWh. The report further stated that power produced at Condit would have been 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 relied on trucking spawning salmon around the dam as a less expensive alternative to fish ladders. This type of proposal was previously rejected by FERC.
The sediment plume is expected to kill some aquatic life below the dam and displace fish as far downstream as Bonneville dam
. It could also harm several generations of an endangered chum
population.
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 some fish and environmental advocates see this case as an important precedent for dam removals to restore free flowing rivers.
White Salmon River
The White Salmon River is a river flowing into the Columbia River Gorge, originating on the slopes of Mount Adams. The lower portion of the river is in the Columbia River Gorge National Scenic Area and some of the upper sections are part of the National Wild and Scenic Rivers system...
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
National Register of Historic Places
The National Register of Historic Places is the United States government's official list of districts, sites, buildings, structures, and objects deemed worthy of preservation...
as an engineering and architecture landmark.
PacifiCorp
PacifiCorp
PacifiCorp is an electric power company in the northwestern United States.PacifiCorp has three primary subsidiaries:# Pacific Power is a regulated electric utility with service territory throughout Oregon, northern California, and southeastern Washington.# Rocky Mountain Power is a regulated...
decommissioned the project due to rising environmental costs, and the dam was intentionally breached
Dam removal
Dam removal is the process of removing out-dated, dangerous, or ecologically damaging dams from river systems. There are thousands of out-dated dams in the United States that were built in the 18th and 19th centuries, as well as many more recent ones that have caused such great ecological damage,...
on October 26, 2011. Condit Dam is the largest dam ever removed in the United States, although its record is not slated to outlast 2012.
Overview and history
The White Salmon is a glacierGlacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
-fed river originating on the slopes of Mount Adams
Mount Adams (Washington)
Mount Adams is a potentially activestratovolcano in the Cascade Range and the second-highest mountain in the U.S. state of Washington.Adams is a member of the Cascade Volcanic Arc, and is one of the arc's largest volcanoes,...
and emptying into the Columbia River
Columbia River
The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...
. Condit Dam is about 3.3 miles (5.3 km) upstream of the confluence. The area below the dam is part of the Columbia River Gorge
Columbia River Gorge
The Columbia River Gorge is a canyon of the Columbia River in the Pacific Northwest of the United States. Up to deep, the canyon stretches for over as the river winds westward through the Cascade Range forming the boundary between the State of Washington to the north and Oregon to the south...
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
Fishing
Fishing is the activity of trying to catch wild fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping....
. Impoundment of the river in 1911 removed 33 miles (53 km) of steelhead habitat and 14 miles (23 km) of salmon
Salmon
Salmon is the common name for several species of fish in the family Salmonidae. Several other fish in the same family are called trout; the difference is often said to be that salmon migrate and trout are resident, but this distinction does not strictly hold true...
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
Camas, Washington
Camas is a city in Clark County, Washington, with a population of 19,355 at the 2010 census. Officially incorporated on June 18, 1906, the city is named after the camas lily, a plant with an onion-like bulb prized by Native Americans. At the west end of downtown Camas is a large Georgia-Pacific...
. Surplus power was sold to Portland customers via a power line across the Columbia River
Columbia River
The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...
. The project was acquired in 1947 by its current owner, PacifiCorp
PacifiCorp
PacifiCorp is an electric power company in the northwestern United States.PacifiCorp has three primary subsidiaries:# Pacific Power is a regulated electric utility with service territory throughout Oregon, northern California, and southeastern Washington.# Rocky Mountain Power is a regulated...
.
The facility consisted of Condit Dam 45°46′02"N 121°32′16"W in Klickitat County, and its impoundment, Northwestern Lake; a woodstave
Woodstave
Woodstave is a common usage of a specific construction material made from wood. The form of the wood is in staves similar to the construction of a wooden barrel as manufactured by coopers of early years. Woodstave was commonly used in the construction of large vessels to contain and/or transport...
pipeline that transports water to a surge tank
Surge tank
A surge tank is a standpipe or storage reservoir at the downstream end of a closed aqueduct or feeder pipe to absorb sudden rises of pressure as well as to quickly provide extra water during a brief drop in pressure...
and auxiliary spillway
Spillway
A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...
; two penstock
Penstock
A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydraulic turbines and sewerage systems. It is a term that has been inherited from the technology of wooden watermills....
s and the powerhouse. Two horizontally mounted francis turbine
Francis turbine
The Francis turbine is a type of water turbine that was developed by James B. Francis in Lowell, Massachusetts. It is an inward-flow reaction turbine that combines radial and axial flow concepts....
s and generators produced electrical power, and the exhausted water rejoined the river about a mile (2 km) downstream of the dam.
The original design had fish ladder
Fish ladder
A fish ladder, also known as a fishway, fish pass or fish steps, is a structure on or around artificial barriers to facilitate diadromous fishes' natural migration. Most fishways enable fish to pass around the barriers by swimming and leaping up a series of relatively low steps into the waters on...
s which were 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 ordered PacifiCorp to alter the dam and add fish ladders to meet environmental codes. PacifiCorp deemed the modifications too expensive and asked to decommission the dam instead. The project operated under annual license extensions until the Federal Energy Regulatory Commission
Federal Energy Regulatory Commission
The Federal Energy Regulatory Commission is the United States federal agency with jurisdiction over interstate electricity sales, wholesale electric rates, hydroelectric licensing, natural gas pricing, and oil pipeline rates...
(FERC) approved decommissioning. The dam was breached at noon (Pacific Time) on October 26, 2011.
At the time, it was the largest U.S. dam to be removed. In 2012, the Elwha Ecosystem Restoration
Elwha Ecosystem Restoration
The Elwha Ecosystem Restoration Project in the United States is the largest dam removal project in history and the second largest ecosystem restoration project in the history of the National Park Service, after the Restoration of the Everglades...
Project on the Olympic Peninsula
Olympic Peninsula
The Olympic Peninsula is the large arm of land in western Washington state of the USA, that lies across Puget Sound from Seattle. It is bounded on the west by the Pacific Ocean, the north by the Strait of Juan de Fuca, and the east by Puget Sound. Cape Alava, the westernmost point in the contiguous...
is slated to remove the larger Elwha Dam
Elwha Dam
The Elwha Dam is a 108-ft high dam located in the United States, in the state of Washington, on the Elwha River approximately upstream from the mouth of the river on the Strait of Juan de Fuca. The dam was built under the direction of Thomas Aldwell...
and Glines Canyon Dam
Glines Canyon Dam
Glines Canyon Dam , built in 1927, is a high concrete arch dam that forms Lake Mills upstream from the Elwha River's mouth....
s.
River flow
Condit dam was required to discharge at least 15 ft³/s (0.4 m³/s) to keep the river channel viable. Surplus water was used by the turbinesWater turbine
A water turbine is a rotary engine that takes energy from moving water.Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy...
for electrical power generation and returned to the river about a mile downstream. Additional flow beyond what the turbines could use was discharged through five tainter gate
Tainter gate
The Tainter gate is a type of radial arm floodgate used in dams and canal locks to control water flow. It is named for Wisconsin structural engineer Jeremiah Burnham Tainter....
s and two sluice gates. The dam crest had a pneumatically actuated hinged crestgate
Floodgate
Floodgates are adjustable gates used to control water flow in flood barriers, reservoir, river, stream, or levee systems. They may be designed to set spillway crest heights in dams, to adjust flow rates in sluices and canals, or they may be designed to stop water flow entirely as part of a levee or...
which was designed to fail catastrophically as a safety relief when flow exceeds 18000 ft³/s (510 m³/s). The river averages 1125 ft³/s (32 m³/s), with flows up to 3500 ft³/s (99 m³/s) fairly common.
Power production
The two turbines could use a maximum of 1,400 ft³/s (40 m³/s) and operate efficiently with as little as 1,100 ft³/s (31 m³/s). In this flow range the plant operated as a run-of-river. Inflow equaled outflow, and both turbines operated continuously to supply base load electricity.When river flow wasn't quite enough for two turbines, operation was cycled between running one and both turbines, based on a daily reservoir draw-down and refill cycle. The cycling was timed to meet peak electrical demands. That is, both turbines operated during hours of high electrical demand and the reservoir was drawn down. A single turbine operated during low electrical demand hours while the reservoir refilled. A similar cycle was used when inflow was less than enough for a single turbine. A weekly cycle was superimposed on the daily cycle that tended to draw down the reservoir during the week and allowed it refill during the weekend. In these cases, known as load factoring, the plant operated as a peaking plant. This mode of operation was greatly reduced through the 1980s and 1990s to appease lakefront cabin owners.
Licensing
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. From 1993 until 2011, PacifiCorp operated the plant under annual license extensions while it sought approval from FERC for the 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 explained the appeal as a backup plan in case decommissioning application failed.
| FERC number | 2342 |
| Dam type | Gravity dam, 471 feet (143.6 m) long, 125 feet (38.1 m) high |
| Location | Mile 3.3 (km 5.3) |
| Concrete used for construction | 30,000 cubic yards (23,000 m³) |
| Floodgates | Five Tainter Tainter gate The Tainter gate is a type of radial arm floodgate used in dams and canal locks to control water flow. It is named for Wisconsin structural engineer Jeremiah Burnham Tainter.... , two sluice Sluice A sluice is a water channel that is controlled at its head by a gate . For example, a millrace is a sluice that channels water toward a water mill... , one hinged crest gate |
| Pipeline | 13.5 ft (4.2 m) dia, 5100 ft (1550 m) long, wood stave |
| Penstocks | 2 x 9 ft (2.7 m) dia x 650 ft (198.1 m), steel and wood stave |
| Turbines Water turbine A water turbine is a rotary engine that takes energy from moving water.Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy... |
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 Hydraulic head Hydraulic head or piezometric head is a specific measurement of water pressure above a geodetic datum. It is usually measured as a water surface elevation, expressed in units of length, at the entrance of a piezometer... |
167.8 ft (51 m) |
| Operation modes | peaking or baseload, depending on available flow |
| Normal lake maximum elevation above SL | 295.2 |
| Reservoir capacity | 1300 acre.ft |
| Useful reservoir storage capacity | 665 acre.ft |
| Surface area | 92 acres (370,000 m²) |
| Average annual Energy Production (1936–1989) | 79,700 MWh MWH MWH may stand for:* International Air Transport Association airport code for Grant County International Airport* MWH Global, an international water engineering consultancy* Men Without Hats, a Canadian New Wave band... |
| Annual operating costs | $400,000 |
| Annual power benefits | $2,896,000 |
| Annual value of power at consumer rates | $4.8 million ($0.06/kWh) |
FERC Proposals
After Pacificorp's license application failed in 1993, FERC prepared an environmental impact statement that proposed installation of a state of the art fish passage system as conditions for license renewal. The enhancements were to include fish ladders to allow upstream migrations of spawning salmon, and other modifications of the dam and operating procedures to allow a 95% survival rate of down stream migrating salmon. These conditions were based on National Marine Fisheries ServiceNational Marine Fisheries Service
The National Marine Fisheries Service is a United States federal agency. A division of the National Oceanic and Atmospheric Administration and the Department of Commerce, NMFS is responsible for the stewardship and management of the nation's living marine resources and their habitat within the...
requirements. FERC's report also reviewed options to decommissioning the project, which it estimated would cost twice as much as the fish passage system.
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
National Marine Fisheries Service
The National Marine Fisheries Service is a United States federal agency. A division of the National Oceanic and Atmospheric Administration and the Department of Commerce, NMFS is responsible for the stewardship and management of the nation's living marine resources and their habitat within the...
, Native American
Native Americans in the United States
Native Americans in the United States are the indigenous peoples in North America within the boundaries of the present-day continental United States, parts of Alaska, and the island state of Hawaii. They are composed of numerous, distinct tribes, states, and ethnic groups, many of which survive as...
Tribal governments with interests in the area, and a number of local and national environmental groups.
PacifiCorp proposal
PacifiCorp's decommissioning plan differed from FERC's decommissioning proposal in how the sediment behind the dam is treated. FERC's plan was to dredge or bypass the sediment while PacifiCorp's plan uses the demolition of the dam to quickly flush as much sediment as possible, thereby minimizing the amount of time the sediment plume harms downstream aquatic life.Breaching the dam involved cutting a 12 x 18 x 100 feet (30.5 m) tunnel in the its base; the final 15 feet (4.6 m) was drilled and blasted. A dredge removed woody sediment from the dam's inside face and, when breached, the reservoir was expected to drain within six hours, but actually drained much faster. The rest of the dam will be cut into blocks and removed for disposal or recycling on-site. As of the date of demolition, Condit dam was the largest dam ever removed for environmental reasons and the largest dam ever removed in the United States.
The quick drainage of the reservoir flushed a large amount of sediment quickly, helping to create 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
Aquatic ecosystem
An aquatic ecosystem is an ecosystem in a body of water. Communities of organisms that are dependent on each other and on their environment live in aquatic ecosystems. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems....
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.
Controversy
There was opposition to the dam removal from Klickitat and Skamania county governments. Objections revolved around the loss of lake front property and water recreation, loss of wetlands and water habitat, and a perception that PacifiCorp was 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 believed was 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
CH2M Hill
CH2M Hill is an American-based global provider of engineering, construction, and operations services for corporations, nonprofits, and federal, state, and local governments. The firm is headquartered in Meridian, an unincorporated area of Douglas County, Colorado in the Denver-Aurora Metropolitan...
calculated that purchasing and upgrading as required by FERC would have led to power production at $64 per MWh, and that for the project to be economically viable it would have to have produced power at $45 to $50 per MWh. The report further stated that power produced at Condit would have been 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 relied on trucking spawning salmon around the dam as a less expensive alternative to fish ladders. This type of proposal was previously rejected by FERC.
The sediment plume is expected to kill some aquatic life below the dam and displace fish as far downstream as Bonneville dam
Bonneville Dam
Bonneville Lock and Dam consists of several run-of-the-river dam structures that together complete a span of the Columbia River between the U.S. states of Oregon and Washington at River Mile 146.1. The dam is located east of Portland, Oregon, in the Columbia River Gorge. The primary functions of...
. It could also harm several generations of an endangered chum
Chum salmon
The chum salmon, Oncorhynchus keta, is a species of anadromous fish in the salmon family. It is a Pacific salmon, and may also be known as dog salmon or Keta salmon, and is often marketed under the name Silverbrite salmon...
population.
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 some fish and environmental advocates see this case as an important precedent for dam removals to restore free flowing rivers.