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John Day

Hydro power plant · Sherman County, Oregon

Nameplate capacity
2,160 MW
Rank in Oregon
#1
of 301 plants
In service since
1968
August 1968

Details

Primary fuel
Hydro
Technology
Conventional Hydroelectric
Operator
USACE Northwestern Division
County
Sherman County
Generating units
16
Share of state capacity
11.25%
Rank among hydro plants in Oregon
#1 of 63
EIA plant code
3082

Generating units

Individual generating units at John Day
UnitTechnologyNameplateSummerOnlineStatus
1Conventional Hydroelectric135 MW135 MW1968Out of service but expected to return to service in next calendar year
10Conventional Hydroelectric135 MW135 MW1969Out of service and NOT expected to return to service in next calendar year
11Conventional Hydroelectric135 MW118 MW1970Operating
12Conventional Hydroelectric135 MW118 MW1970Operating
13Conventional Hydroelectric135 MW135 MW1970Operating
14Conventional Hydroelectric135 MW118 MW1971Out of service but expected to return to service in next calendar year
15Conventional Hydroelectric135 MW135 MW1971Operating
16Conventional Hydroelectric135 MW135 MW1971Operating
2Conventional Hydroelectric135 MW135 MW1968Operating
3Conventional Hydroelectric135 MW129 MW1968Out of service but expected to return to service in next calendar year
4Conventional Hydroelectric135 MW118 MW1968Operating
5Conventional Hydroelectric135 MW135 MW1969Operating
6Conventional Hydroelectric135 MW135 MW1969Operating
7Conventional Hydroelectric135 MW135 MW1969Operating
8Conventional Hydroelectric135 MW118 MW1969Out of service but expected to return to service in next calendar year
9Conventional Hydroelectric135 MW118 MW1969Operating

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 Oregon

The DallesHydro1,820 MW
BonnevilleHydro1,162 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 2,160 MW solar plant and a 2,160 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 Oregon power plants · What Oregon actually generates