Wells Dam
Name officialWells Hydroelectric Project[1]
Dam crossesColumbia River
Res nameLake Pateros
LocationChelan / Douglas counties, Washington
OperatorDouglas County Public Utility District
Dam length4,460 feet (1,360 m)[2]
Construction beganJuly 12, 1962[1]
OpeningAugust 22, 1967
Res capacity total331,200 acre feet
Plant turbines
  • 10 Total MW[3]
  • 7x 89.0 MW
  • 3x 77.4 MW
Plant capacity855.2 MW [3]
Plant annual gen3,502.38 GWh[4]
Coordinates47°56′43.44″N 119°51′57.6″W
Dam width crest169 feet (52 m)[5]
Spillway count11[5]
Dam height foundation186 feet (57 m)[5]

Wells Dam is a hydroelectric embankment dam located on the Columbia River, downstream from the confluence of the Okanogan River, Methow River, and the Columbia River in Washington state. The dam, associated structures, and machinery make up the Wells Hydroelectric Project. It is owned and operated by Douglas County Public Utility District.

It has produced electricity since August 22, 1967. Its operating license from the US Federal Energy Regulatory Commission is next up for renewal in 2052.[6] The Wells project has ten generating units rated at a combined 855.2 megawatts.[3] In addition to the Douglas County and Okanogan County public utility districts, the project provides electricity to Puget Sound Energy, Portland General Electric, PacifiCorp, Avista Corporation,[7] and the Confederated Tribes of the Colville Reservation.[8]

Its reservoir is named Lake Pateros. Just below and adjacent is Carpenter Island boat launch and fish hatchery river access. Lake Pateros is not deep but a high volume of water moves through it. Thus, low-head, high-volume Kaplan turbine runners drive generation.[9]

Hydroelectric power capacity

GeneratorNameplate Capacity (MW)[3]
U-177.4
U-289.0
U-389.0
U-489.0
U-589.0
U-689.0
U-789.0
U-877.4
U-977.4
U-1089.0
Total855.2

See also

References

  1. ^ "Wells Project License". Douglas County PUD. Public Utility District No. 1 of Douglas County. Retrieved 21 March 2026.
  2. ^ "Wells Project". Douglas County PUD. Public Utility District No. 1 of Douglas County. Retrieved 21 March 2026.
  3. ^ "January 2026: EIA 860M". Preliminary Monthly Electric Generator Inventory. U.S. Energy Information Administration. Retrieved 21 March 2026.
  4. ^ "2024: EIA-923". Form EIA-923 detailed data with previous form data. U.S. Energy Information Administration. Retrieved 21 March 2026.
  5. ^ "Property ID: 710488 Wells Dam Hydrocombine". WISAARD. Washington State Department of Archaeology and Historic Preservation. Retrieved 27 March 2026.
  6. ^ Christine Pratt (2013-05-30). "Wells Dam gets new 40-year license". The Wenatchee World. Retrieved May 31, 2018.
  7. ^ "Wells Hydroelectric Project". Foundation for Water & Energy Education. Retrieved December 18, 2021.
  8. ^ "How the Confederated Tribes of the Colville Reservation Balance Hydropower and Natural Resource Protection". Hydro Leader. December 14, 2021. Retrieved December 18, 2021.
  9. ^ "Wells Dam Rehabilitation Project". Toshiba America Energy Systems Corp. Retrieved May 31, 2018.