Seminoe Dam Explained

Seminoe Dam
Location Map:Wyoming
Location Map Caption:Location of Seminoe Dam in Wyoming
Coordinates:42.1558°N -106.9083°W
Country:United States
Location:Carbon County, Wyoming
Status:In use
Construction Began:1936
Opening:1939
Owner:U.S. Bureau of Reclamation
Dam Type:Concrete thick gravity-arch
Dam Height:295feet[1]
Dam Length:530feet
Dam Width Crest:15feet
Dam Width Base:85feet
Dam Volume:210000yd3
Dam Crosses:North Platte River
Spillway Count:1
Spillway Type:Gated concrete tunnel
Spillway Capacity:48500cuft/s
Res Name:Seminoe Reservoir
Res Capacity Total:1017279acre.ft[2]
Res Catchment:7210mi2
Res Surface:20291acres
Res Max Depth:206feet
Plant Hydraulic Head:166feet[3]
Plant Turbines:3x 15 MW
Plant Capacity:45 MW
Plant Annual Gen:96,406,970 KWh (2007)

Seminoe Dam is a concrete thick-arch dam on the North Platte River in the U.S. state of Wyoming. The dam stores water for irrigation and hydroelectricity generation and is owned and operated by the U.S. Bureau of Reclamation. It is the uppermost dam on the North Platte River and is located directly upstream from the Kortes Dam. It lies in a narrow, isolated canyon formed by the North Platte cutting through the Seminoe Mountains about 40miles northeast of Rawlins. The 295feet dam forms Seminoe Reservoir, which covers more than 20000acres when full.[4] Seminoe State Park is adjacent to the reservoir. The small village of Seminoe Dam abuts the dam and reservoir and provides residence for the dam attendants and park services personnel.

History

This dam was first proposed in the 1930s as part of the Bureau of Reclamation's Kendrick Project, which would regulate the flow of the North Platte River in order to improve agriculture in the valleys surrounding Casper, Wyoming.[5] Originally known as the Casper-Alcova Project, it was authorized by the National Industrial Recovery Act on June 16, 1933 in response to the Great Depression. The project was renamed the Kendrick Project on August 9, 1937 in honor of Wyoming politician John B. Kendrick.[6]

In 1934, Winston Brothers Company and Associates won the construction contract for Seminoe Dam. Groundbreaking of the site was on February 20, 1936, with preliminary blasting and excavations. The diversion tunnel for the North Platte was completed on January 17, 1937, with one fatality, and by May of that year, a cofferdam was completed to a sufficient height to divert the river into the new channel. Concrete pouring began on January 19, 1938, and the last bucket was emptied on December 21, 1938. Water storage began on April 2, 1939, when the outlet tunnels were closed. The dam's power station was finished and the entire project was declared operational on August 3, 1939. A total of two deaths and several serious injuries resulted from the construction, and a pair of active faults that cut across the canyon near the dam site had to be excavated and filled in.[6]

On March 25, 1969, a helicopter experienced engine problems and crashed into the rocky canyon near Seminoe dam killing Bureau of Reclamation employees David McMillan and Howard Leroy Gates. (Altoona Mirror, April 21, 1969)

When the project was first completed, it delivered water to just 600acres, but has progressed steadily, and by 1980 supplied irrigation water to 22581acres in the Casper valley.[3]

A $2.5 billion 900 MW / 9 GWh (10-hour) pumped-storage hydroelectricity plant is scheduled to use Seminoe reservoir as the lower reservoir, and a new dam and reservoir as the upper.[7]

Recreation

The Seminoe Reservoir is stocked with fish by the Wyoming Game and Fish Commission, and is open to boating and fishing, although access to the shoreline is limited and sometimes difficult due to the lack of development and distance from major cities.

See also

External links

Notes and References

  1. Web site: Dimensions. U.S. Bureau of Reclamation. Kendrick Project. 2008-08-30. 2011-02-27.
  2. Web site: Hydraulics and Hydrology. U.S. Bureau of Reclamation. Kendrick Project. 2008-08-30. 2011-02-27.
  3. Web site: Kendrick Project. U.S. Bureau of Reclamation. 2009-12-22. 2011-02-27.
  4. Web site: Seminoe Reservoir. Wyoming State Water Plan. Platte River Basin Water Atlas. 2011-02-27.
  5. News: Killingbeck . Dale . 2024-05-05 . Irrigating Wyoming – It’s Complicated, Involves Lots of Dams And Careful Monitoring . 2024-05-06 . Cowboy State Daily . en.
  6. Web site: Klajic. Leisl A.. The Kendrick Project (Casper-Alcova). U.S. Bureau of Reclamation. Bureau of Reclamation History Program. 2000. 2011-02-27.
  7. Web site: Murray . Cameron . rPlus Energies submits Final License Application for 9GWh pumped hydro plant in Wyoming . Energy Storage News . 26 January 2023.