Nameplate capacity
259 MW
Rank in Oklahoma
#38
of 147 plants
In service since
1968
May 1968
Details
- Primary fuel
- Hydro
- Technology
- Hydroelectric Pumped Storage
- Operator
- Grand River Dam Authority
- County
- Mayes County
- Generating units
- 6
- Share of state capacity
- 0.71%
- Rank among hydro plants in Oklahoma
- #1 of 11
- EIA plant code
- 2982
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 1 | Hydroelectric Pumped Storage | 43 MW | 40 MW | 1968 | Operating |
| 2 | Hydroelectric Pumped Storage | 43 MW | 40 MW | 1968 | Operating |
| 3 | Hydroelectric Pumped Storage | 43 MW | 40 MW | 1968 | Operating |
| 4 | Hydroelectric Pumped Storage | 43 MW | 41 MW | 1971 | Operating |
| 5 | Hydroelectric Pumped Storage | 43 MW | 42 MW | 1971 | Operating |
| 6 | Hydroelectric Pumped Storage | 43 MW | 39 MW | 1971 | Operating |
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 Oklahoma
| Canadian Hills Wind | Wind | 294 MW |
| Maverick Wind Project, LLC | Wind | 288 MW |
| 25 Mile Creek | Wind | 250 MW |
| Rush Springs Wind | Wind | 250 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 259 MW solar plant and a 259 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 Oklahoma power plants · What Oklahoma actually generates