Enloe Dam and Powerplant
Encyclopedia
The Enloe Dam, also known as the Similkameen Dam, and its powerplant, are located on the Similkameen River
about 4 miles (6.4 km) west-northwest of Oroville, Washington
. Located just above Similkameen (Coyote) Falls, the concrete arch-gravity dam
stands about 54 feet (16.5 m) high, with a crest length of about 290 feet (88.4 m), built between 1916 and 1923. The dam was named after the president of the Okanogan Valley Power Company, Eugene Enloe. The dam was operated to generate power at its powerplant, located about 850 feet (259.1 m) downstream from the dam.
and Oroville
, as well as the nearby Owasco, Ivanhoe, Ruby and Canba mines. Attempts by Hagerty's estate to sell the dam in 1913 met no interest, partly due to the poor state of the crib dam. Eugene Enloe of the Okanogan Valley Power Company was able to secure the rights to the site in 1916, hiring C.F. Uhden to design the dam that year. Construction did not start until 1919 and was completed in 1920 at a cost of $350,000, $150,000 of it Enloe's money. Enloe sold the dam and powerplant in 1923 to Washington Water Power Company, who added a second penstock.
system at less cost. The dam's reservoir extends 2 miles (3.2 km) up the Similkameen River. Largely silted up, it is just 9 feet (2.7 m) deep. Storage capacity is only 507 acre.ft.
The concrete powerhouse is in a partly ruinous state, and options have been presented to stabilize or demolish the structure when the proposed new hydroelectric development is undertaken. The powerhouse was fed by two wood stave penstocks, 7 feet (2.1 m) in diameter, running to Pelton wheel
s driving two 1.6 megawatt generators. The generator hall stands next to a heavily-built transformer vault.
The Okanogan Public Utility District obtained a new license for power generation from the Federal Energy Regulatory Commission
in 1983, but the license was withdrawn in 1986 because the dam's impact on anadromous fish had not been addressed. A second license for a 4.1 megawatt plant was granted in 1996, but was again rescinded on the same grounds in 2000. Yet another application was submitted in August 2008, seeking to build a new powerplant to generate 9 megawatts, fed by a new intake channel.
Enloe Dam was listed on the National Register of Historic Places
on October 18, 1978 as an example of early power development in rural Washington.
Similkameen River
The Similkameen River runs through southern British Columbia, eventually discharging into the Okanogan River near Oroville, Washington in the United States. The river is approximately long, and its drainage basin is in area...
about 4 miles (6.4 km) west-northwest of Oroville, Washington
Oroville, Washington
Oroville is a town in Okanogan County, Washington, United States. The population was 1,686 at the 2010 census.-Geography:Oroville is located at ....
. Located just above Similkameen (Coyote) Falls, the concrete arch-gravity dam
Arch-gravity dam
An arch-gravity dam, curved-gravity dam or arched dam is a dam with the characteristics of both an arch dam and a gravity dam. It is a dam that curves upstream in a narrowing curve that directs most of the water against the canyon rock walls, providing the force to compress the dam...
stands about 54 feet (16.5 m) high, with a crest length of about 290 feet (88.4 m), built between 1916 and 1923. The dam was named after the president of the Okanogan Valley Power Company, Eugene Enloe. The dam was operated to generate power at its powerplant, located about 850 feet (259.1 m) downstream from the dam.
History
The dam replaced a wood crib dam started in 1903 by J.M. Hagerty, a local entrepreneur, and completed a year after his death. The dam fed a generating plant in a wooden powerplant below the dam and falls. Power went to the towns of NighthawkNighthawk, Washington
Nighthawk is an unincorporated community on the Similkameen River in Okanogan County, Washington state, USA. It was named for a nearby mine. Nighthawk is a logging area along Loomis-Oroville Highway west-northwest of Oroville, Washington. Nighthawk also features a border crossing and is...
and Oroville
Oroville, Washington
Oroville is a town in Okanogan County, Washington, United States. The population was 1,686 at the 2010 census.-Geography:Oroville is located at ....
, as well as the nearby Owasco, Ivanhoe, Ruby and Canba mines. Attempts by Hagerty's estate to sell the dam in 1913 met no interest, partly due to the poor state of the crib dam. Eugene Enloe of the Okanogan Valley Power Company was able to secure the rights to the site in 1916, hiring C.F. Uhden to design the dam that year. Construction did not start until 1919 and was completed in 1920 at a cost of $350,000, $150,000 of it Enloe's money. Enloe sold the dam and powerplant in 1923 to Washington Water Power Company, who added a second penstock.
Description
The dam features an unregulated overflow spillway whose height can be augmented by flashboards. The powerplant replaced a small run-of-river plant which received water from a diversion channel. In 1923 the site was purchased by the Washington Water Power Company. In 1942 the WWPC was purchased by the Okanogan Public Utility District, which then ceased operations at Enloe Dam in 1958, as power was available from the Bonneville Power AdministrationBonneville Power Administration
The Bonneville Power Administration is an American federal agency based in the Pacific Northwest. BPA was created by an act of Congress in 1937 to market electric power from the Bonneville Dam located on the Columbia River and to construct facilities necessary to transmit that power...
system at less cost. The dam's reservoir extends 2 miles (3.2 km) up the Similkameen River. Largely silted up, it is just 9 feet (2.7 m) deep. Storage capacity is only 507 acre.ft.
The concrete powerhouse is in a partly ruinous state, and options have been presented to stabilize or demolish the structure when the proposed new hydroelectric development is undertaken. The powerhouse was fed by two wood stave penstocks, 7 feet (2.1 m) in diameter, running to Pelton wheel
Pelton wheel
The Pelton wheel is an impulse turbine which is among the most efficient types of water turbines. It was invented by Lester Allan Pelton in the 1870s. The Pelton wheel extracts energy from the impulse of moving water, as opposed to its weight like traditional overshot water wheel...
s driving two 1.6 megawatt generators. The generator hall stands next to a heavily-built transformer vault.
Redevelopment
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...
in 1983, but the license was withdrawn in 1986 because the dam's impact on anadromous fish had not been addressed. A second license for a 4.1 megawatt plant was granted in 1996, but was again rescinded on the same grounds in 2000. Yet another application was submitted in August 2008, seeking to build a new powerplant to generate 9 megawatts, fed by a new intake channel.
Enloe Dam was listed on 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...
on October 18, 1978 as an example of early power development in rural Washington.
External links
- Enloe Dam, On Similkameen River, Oroville vicinity, Okanogan, WA at the Historic American Engineering Record
- Enloe Dam, Power House, On Similkameen River, Oroville vicinity, Okanogan, WA at HAER