Cougar Dam
Cougar Dam | |
---|---|
Location | Lane County, Oregon, U.S. |
Coordinates | 44°7′44″N 122°14′25″W / 44.12889°N 122.24028°W |
Opening date | 1964[1] |
Operator(s) | Cenwp[1] |
Dam and spillways | |
Impounds | South Fork McKenzie River |
Height | 519 feet (158 m)[1] |
Length | 1,600 feet (488 m)[1] |
Reservoir | |
Creates | Cougar Reservoir |
Total capacity | 219,000 acre-feet (0.270 km3)[1] |
Catchment area | 210 square miles (544 km2)[1] |
Surface area | 1,280 acres (520 ha)[1] |
Cougar Dam is a 519-foot (158 m) tall rockfill hydroelectric dam in the U.S. state of Oregon. It has a gated concrete spillway and a powerhouse with two turbines totaling 25 megawatts of electric power.[2][3]
The dam impounds the
In 2005, the Willamette temperature control facility was constructed to help regulate the water temperature released to the river below Cougar Dam in an attempt to reduce the negative effects on salmon migration.[5] To further help recover threatened chinook salmon and bull trout populations,[6][7] in the Willamette River Basin, the U.S. Army Corps of Engineers constructed a fish collection and sorting facility on the South Fork McKenzie River below Cougar Dam which was completed in 2010.[5] From 2003 to 2005, state-of-the-art turbine runners were installed in the turbine-generator units at the Cougar powerhouse, and were designed to resist cavitation and operate efficiently at very large head ranges.[2]
Background
Cougar Dam was completed in 1963 at a cost of $54.2 million and the two turbine units were completed in 1964.
Temperature control tower
The original intakes for the powerhouse and regulating outlet were deep and pulled water from the bottom of the reservoir which is much colder than the surface water.[9] During the spring and summer, the release of unnaturally cold water into the McKenzie River reduces salmon migration and productivity.[9] In the fall, the reservoir level is considerably lower and the warmer water from the surface enters the intakes and makes the river downstream unnaturally warm which causes salmon eggs to hatch several months too early. In order to help control the temperature of water discharged below the dam, the original intake tower was modified by adding a 302-foot (92 m) tall wet well. The wet well has three adjustable gates at various levels so that different temperature water can be mixed in the wet well to a desired temperature.[9] The mixed water enters the existing regulating and penstock intakes.[8] By controlling the temperature of the water released from the dam, the impacts on the McKenzie River are greatly reduced.[9]
Fish collection and sorting facility
When the Cougar Dam was originally constructed, it contained adult and juvenile fish passage facilities that helped fish move past the dam. However, fish no longer migrated to the facility, and it became ineffective.[5] The Army Corps of Engineers decided to construct a new collection and sorting facility to collect, sort, and transport fish upstream and downstream of the dam. The new facility would cost $14.7 million and include a fish ladder, presort pool, sorting facility, and two pump structures for water supply.[10] At the collection and sorting facility, adult salmon and bull trout will be loaded on trucks and released into high-quality habitats above Cougar Dam in an effort to recover threatened salmon and bull trout populations.[5]
Replacement of turbines
The runners from the two turbines in the Cougar powerhouse experienced significant cavitation damage during operation and by the 1980s they were in need of repair and had to be taken out of service four times a year for inspections and repair.
See also
- List of lakes in Oregon
References
- ^ a b c d e f g "Cougar Dam". National Performance of Dams Project Directory. Department of Civil and Environmental Engineering, Stanford University. Archived from the original on July 16, 2011. Retrieved May 9, 2011.
- ^ a b c d e f g h G. Charles Allen Jr., U.S. Army Corps of Engineers. "Seeking Best Value During Equipment Procurement". Hydro World. HCI Publications, Inc., a division of PennWell Corporation. Retrieved May 9, 2011.
- ^ a b c d e "Cougar Dam and Reservoir". Archived from the original on May 17, 2011. Retrieved May 9, 2011.
- ^ a b "Cougar Dam". Bonneville Power Administration. Archived from the original on July 26, 2011. Retrieved May 9, 2011.
- ^ a b c d "Corps Completes Cougar Dam Fish Collection Facility To Aid McKenzie River Salmon, Bull Trout". Columbia Basin Bulletin. Intermountain Communications. August 27, 2010. Archived from the original on October 8, 2011. Retrieved May 9, 2011.
- ^ "5-Year Review: Summary & Evaluation of Upper Willamette River Steelhead and Upper Willamette River Chinook" (PDF). National Oceanic and Atmospheric Administration. 2011. Retrieved 2013-12-03.
- ^ "Species Profile-Bull Trout (Salvelinus confluentus)". U.S. Fish and Wildlife Service. Retrieved 2013-12-05.
- ^ a b c Bird, Brad; Stephen J. Schlenker; Nathan T. Higa (October 8, 2003). "Design of a Multi-Level Intake for Temperature Control featuring a Lake Tap at Cougar Dam, Vida, Oregon" (PDF). U.S. Army Corps of Engineers. Archived from the original (PDF) on July 21, 2011. Retrieved May 9, 2011.
- ^ a b c d e "Cougar Reservoir Water Temperature Control and Upstream Passage Project". Oregon Department of Fish and Wildlife. Archived from the original on August 23, 2011. Retrieved May 9, 2011.
- ^ "The Projectwise Project Showcase". Bentley Systems. 2011. Retrieved May 9, 2011.