Oahe — Plant Summary
- EIA Plant ID
- 3356
- Capacity
- 786.1 MW
- Primary Fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Status
- Operating
- Location
- Hughes, SD
- Operating Since
- 1962
- Generators
- 7
- Operator
- USACE-Omaha
- Parent Company
- —
- Annual Generation
- 2,188,759 MWh
- Capacity Factor
- 31.7%
- Balancing Authority
- Southwest Power Pool
- ISO/RTO
- SPP
- NERC Region
- MRO
Oahe
OperatingHydro
Ranked #1 of 4 Hydro plants in SD#32 of 1454 nationally
786.1 MW Hydro operating in Hughes, SD — Southwest Power Pool
EIAGEMWD
786.1 MW
Nameplate Capacity
7
Generators
units
Conventional Hydroelectric
Technology
1962
Operating Since
Location
Coordinates
44.4504, -100.3866
County
Hughes, SD
Nearby Plants
- Ft. PierreDistillate Oil6 MW · 9.2 km
- Pierre SolarSolar1 MW · 9.3 km
Ownership & Operator
Owner data does not fully agree across sources.
EIA typically reports the operating utility, while GEM resolves to the financial owner or parent corporation. Both can be correct.
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | USACE-Omaha | US Army Corps of Engineers - Omaha District | — |
| Owner(s) | USACE-Omaha | US Army Corps of Engineers - Omaha District [100%] | — |
| Status | Operating | operating | — |
Ownership Chain
GEM identifies the owner as US Army Corps of Engineers - Omaha District [100%]
This entity is not yet in the GEM ownership database — chain unavailable.
About
The Oahe Dam is a large earthen dam on the Missouri River, just north of Pierre, South Dakota, United States. Begun in 1948 and opened in 1962, the dam creates Lake Oahe, the fourth-largest man-made reservoir in the United States. The reservoir stretches 231 miles (372 km) up the course of the Missouri to Bismarck, North Dakota. The dam's power plant provides electricity for much of the north-central United States. It is named for the Oahe Indian Mission established among the Lakota Sioux in 1874.
Read more on WikipediaThe Oahe hydroelectric plant is located in Hughes County, South Dakota. It has a total capacity of 786.1 MW across 7 generators, making it the largest of three hydroelectric plants in the state. Nationally, it ranks as the 32nd largest out of 194 hydroelectric facilities. The plant began operating in 1962 and is operated by the US Army Corps of Engineers (USACE-Omaha). The primary fuel source is water ("WAT").
In the most recent year with available data, Oahe generated 2,188,759 MWh of electricity, achieving a capacity factor of 31.7%. The plant operates within the Southwest Power Pool (SPP) balancing authority and the Midwest Reliability Organization (MRO) NERC region.
Generated from EIA, GEM, and public data sources
Engineering & Generators
Grid Context
NERC Region
MRO
Balancing Authority
Southwest Power Pool
Grid Voltage
230 kV
Regulatory Status
RE
Entity Type
Federal
Sector
Electric Utility
Generation
100.8K MWh
Latest Month
2.2M MWh
Annual Generation
31.7%
Capacity Factor
Jan 2022 – Dec 2024
Financial Data
No financial data available for this plant.
Pricing & Market Data
HIGH confidencePoint of Interconnection
Nearest Substation
Oahe Substation · 230 kV
Substation Distance
0 km
Coord Source
OSM spatial
Market Position
ISO/RTO Market
SPP
LMP Node
WAUE.OAHE.1
Pricing Hub
SPP North Hub
Node Source
Curated node match
News & Articles (8)Beta
Last updated 2026-03-26
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