The Electron Hydroelectric Project, originally known as the Puyallup Project, is a
hydroelectric power plant operated by Electron Hydro LLC on the
Puyallup River
The Puyallup River ( ) is a river in the U.S. state of Washington. About long, it is formed by glaciers on the west side of Mount Rainier. It flows generally northwest, emptying into Commencement Bay, part of Puget Sound. The river and its tribu ...
in
Pierce County,
Washington
Washington commonly refers to:
* Washington (state), United States
* Washington, D.C., the capital of the United States
** A metonym for the federal government of the United States
** Washington metropolitan area, the metropolitan area centered o ...
. It generates of electricity
and is operated and maintained by approximately 20 full-time employees.
Location
It is located along the Puyallup River near
Kapowsin, Pierce County, approximately southeast of
Tacoma and southeast of
Seattle
Seattle ( ) is a seaport city on the West Coast of the United States. It is the seat of King County, Washington. With a 2020 population of 737,015, it is the largest city in both the state of Washington and the Pacific Northwest regio ...
in the western foothills of
Mount Rainier.
Technology
The project, which was completed in 1904, draws water from the Puyallup River behind the Electron Diversion Dam, then funnels it to the Electron power plant via a span of wooden
flume
A flume is a human-made channel for water, in the form of an open declined gravity chute whose walls are raised above the surrounding terrain, in contrast to a trench or ditch. Flumes are not to be confused with aqueducts, which are built to t ...
running along the side hills of the winding river valley while the river runs down a steep canyon. The wooden flume has a cross section of and can supply up to of water per second to the turbines of the Electron powerhouse.
Original construction took approximately 14 months to complete. The grade is uniform and runs at seven feet of elevation per mile.
A light railway line was built on top of the flume to shuttle maintenance workers and equipment. It is known as "the crookedest railway in the world,"
but it is not the only railway line with this claim.
The flume and the railway were rebuilt in the 1940s, then again in 1985 on the original track. The original wood frames were replaced with over 12,000 steel frames, roughly on center. The flume is supported with over 6,000 bents. The flume is lined with 5.5 million board feet of fir. Electron Hydro, LLC is in the process of rebuilding the wood liner with
Alaska yellow cedar and possibly coated with
Polyurea
Polyurea is a type of elastomer that is derived from the reaction product of an isocyanate component and a synthetic resin blend component through step-growth polymerization. The isocyanate can be aromatic or aliphatic in nature. It can be mon ...
. It is notable for likely being the largest flume in use for hydroelectric projects in the United States.
Fish passage facilities
The upstream migration of spawning adult
salmon
Salmon () is the common name for several commercially important species of euryhaline ray-finned fish from the family Salmonidae, which are native to tributaries of the North Atlantic (genus ''Salmo'') and North Pacific (genus '' Oncorhy ...
and
rainbow trout is possible by a concrete,
fish ladder
A fish ladder, also known as a fishway, fish pass, fish steps, or fish cannon is a structure on or around artificial and natural barriers (such as dams, locks and waterfalls) to facilitate diadromous fishes' natural migration as well as move ...
built alongside the wooden diversion dam opposite the flume intake. Migrating juvenile fish that inadvertently enter the wooden flume downstream will be captured alive and placed back in the Puyallup River using a trap-and-haul facility, which is located in the storage reservoir’s forebay.
Controversy
On July 29, 2020, Electron Hydro, the company that owns and operates the dam, experienced an industrial accident in which crumb rubber debris was released into the Puyallup River. Astro-turf used as part of a cofferdam broke loose from the HDPE liner and was spilled into the river. The company took immediate action to rectify the spill.
References
External links
*
*{{HAER , survey=WA-12 , id=wa0187 , title=Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA , photos=89 , dwgs=6 , data=26 , cap=6
Historic American Engineering Record in Washington (state)
Hydroelectric power companies of the United States
Puyallup, Washington
Light rail in Washington (state)
Energy infrastructure completed in 1904
1904 establishments in Washington (state)
Hydroelectric power plants in Washington (state)
Puget Sound Energy
Puyallup River