Garrison

Hydro power plant · Mercer County, North Dakota

Nameplate capacity
583 MW
Rank in North Dakota
#6
of 63 plants
In service since
1956
January 1956

Details

Primary fuel
Hydro
Technology
Conventional Hydroelectric
Operator
USACE-Omaha
County
Mercer County
Generating units
5
Share of state capacity
5.20%
Rank among hydro plants in North Dakota
#1 of 1
EIA plant code
2815

Generating units

Individual generating units at Garrison
UnitTechnologyNameplateSummerOnlineStatus
1Conventional Hydroelectric122 MW102 MW1956Operating
2Conventional Hydroelectric122 MW102 MW1956Operating
3Conventional Hydroelectric122 MW102 MW1956Operating
4Conventional Hydroelectric109 MW102 MW1960Operating
5Conventional Hydroelectric109 MW102 MW1960Operating

Nameplate is the maximum rated output; summer capacity is what the unit can reliably deliver on a hot day, which is typically lower.

Similarly sized plants in North Dakota

Milton R YoungCoal734 MW
Leland OldsCoal656 MW
CoyoteCoal450 MW
Lonesome Creek StationNatural gas363 MW

About this data

From EIA’s inventory of operable generators, May 2026 release. Capacity is nameplate — the maximum rated output of the equipment, not what the plant actually generates over a year, which depends on how often it runs. A 583 MW solar plant and a 583 MW nuclear plant have the same entry here and produce very different amounts of electricity.

“In service since” is the earliest in-service date among the units still listed, so a site rebuilt around newer equipment can read as younger than the site itself. All North Dakota power plants · What North Dakota actually generates