US Army Corps of Engineers
Northwestern Division Website

Libby Dam

Libby Dam and Lake Koocanusa

Published Sept. 29, 2015
Reservoir Elevations
  • Normal full pool: 749.5 meters (2,459 feet)
  • Normal minimum pool: 697.0 meters (2,287 feet)
  • Surface area at full pool: 18,830 hectares (46,500 acres)
  • Total storage capacity: 7.2 kilometers3 (5,869,000 acre-feet)
  • Usable storage capacity 6.1 kilometers3 (4,980,000 acre-feet)

Dam, Concrete Gravity

  • Deck Elevation: 753.5 meters (2,472 feet)
  • Length: 916.0 meters (3,055 feet)
  • Approximate height above foundation: 112.8 meters (370 feet)
  • Maximum spillway capacity: 4,106 meters3/sec (145,000 cfs)
  • Maximum low level outlets capacity: 1,730 meters3/sec (61,000 cfs)

Power Facilities

  • Designed ultimate installation: 8 units at 105 MW total 840 MW
  • Currently installed: 5 units at 120 MW total 600 MW
  • Date power commercially available: August 24, 1975
  • Head at full pool: 107.0 meters (352 feet)
  • Maximum turbine discharge of 5 units at full pool: 745.6 meters3/sec (26,500 cfs)

More information on Libby Dam is available from the USACE, Seattle District.