SEMINOE
OperatingHydro power plant
- Capacity
- 52 MW
- Primary fuel
- Hydro
- County
- Carbon County
- Operator
- U S BUREAU OF RECLAMATION
- Status
- Operating
- Commissioned
- 1939
- EIA plant ID
- 4182
- Generators
- 3
- Technology
- Conventional Hydroelectric
- Net generation (2024)
- 137 GWh
- Capacity factor (2024, EIA nameplate)
- 30%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 42.1562, -106.9084
SEMINOE, a 52 MW Hydro power plant in Carbon County, Wyoming. Operated by U S BUREAU OF RECLAMATION, commissioned 1939.
How SEMINOE compares
With 52 MW of capacity, SEMINOE ranks 23rd among the 53 operating power plants Bywatts maps in Wyoming and 2nd of the 14 operating Hydro plants in the state. It accounts for about 17% of Wyoming's operating Hydro capacity and 0.6% of all operating capacity in the state. Nationally it is the 275th-largest of the 1,243 operating Hydro plants in the database. Commissioned in 1939, it is older than 90% of the 53 operating Wyoming plants with a recorded commissioning year. Its operator, U S BUREAU OF RECLAMATION, runs 13 operating plants in Wyoming totaling 297 MW. It shares Carbon County with 4 other operating plants, including SEVEN MILE HILL and DUNLAP.
EIA-860 lists 3 generators at the site with 52 MW of nameplate capacity, all conventional hydroelectric technology. Net generation was 137 GWh in 2024 (a 30% capacity factor), about 2.5 times its 2022 output.
Grid neighborhood
The nearest named substation is SEMINOE, under 0.1 miles away; the closest transmission line found within 10 miles is a 115 kV line owned by WAPA-- WESTERN AREA POWER ADMINISTRATION, under 0.1 miles away. Another 2 operating power plants totaling 103 MW sit within 25 miles; the largest is FREMONT CANYON (67 MW, Hydro).
Computed by Bywatts from HIFLD power plant, substation and transmission line records and EIA-860/923 survey data; distances are straight-line. Sources and methodology
Weather peril exposure
SEMINOE is a 52 MW hydro power plant in Carbon County, WY, operated by U S BUREAU OF RECLAMATION, commissioned in 1939. Carbon County carries low modeled catastrophe exposure in the FEMA National Risk Index, scoring 1.2 of 5 at the 5th national percentile. Riverine flooding is the leading peril, rated Relatively Low by FEMA at the 87th percentile.
The Bywatts loss layer is calibrated to solar PV hardware, so it is not applied to a hydro plant. The ratings below are the FEMA National Risk Index county hazard ratings for this location.
Carbon County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Riverine flooding | Relatively Low | 87th | 4.5 of 5 | 0.29 |
| Wildfire | Relatively Low | 81st | 4.2 of 5 | <0.01 |
| Earthquake | Relatively Low | 78th | 4.1 of 5 | <0.01 |
| Ice storm | Relatively Low | 60th | 3.4 of 5 | 0.02 |
| Winter weather | Relatively Moderate | 44th | 2.8 of 5 | 24.5 |
| Lightning | Relatively High | 22nd | 1.9 of 5 | 44.2 |
| Hail | Very Low | 15th | 1.6 of 5 | 0.23 |
| Tornado | Very Low | 10th | 1.4 of 5 | 0.37 |
| Strong wind | Very Low | 9th | 1.4 of 5 | 0.23 |
Perils not assessed in Carbon County
These perils carry no usable National Risk Index figure for this county, so they are excluded from the scoring rather than scored zero. A zero would claim the peril was assessed and found benign.
| Peril | Why it is not scored |
|---|---|
| Hurricane | FEMA rating is "Not Applicable" for this county |
| Coastal flooding | FEMA rating is "Not Applicable" for this county |
| Heat wave | FEMA rating is "No Rating" for this county |
Model hail, wind and flood exposure for Carbon County in the weather risk calculator
Ratings are the FEMA National Risk Index county hazard ratings; the peril score is a Bywatts transform of the FEMA national percentile. Full data sources and the solar vulnerability methodology are in the weather risk calculator.
Modeled estimate for screening and negotiation. Built from FEMA National Risk Index county hazard data and a solar vulnerability layer documented above. Not a quote, a binder, or actuarial advice, and not a substitute for a carrier's own model. Hazard data: FEMA National Risk Index December 2025, synced 2026-07-24. Resolution is county level, not site level.