YELLOWTAIL
OperatingHydro power plant
- Capacity
- 250 MW
- Primary fuel
- Hydro
- County
- Big Horn County
- Operator
- U S BUREAU OF RECLAMATION
- Status
- Operating
- Commissioned
- 1966
- EIA plant ID
- 2204
- Generators
- 4
- Technology
- Conventional Hydroelectric
- Net generation (2024)
- 798 GWh
- Capacity factor (2024, EIA nameplate)
- 33%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 45.3072, -107.9581
YELLOWTAIL, a 250 MW Hydro power plant in Big Horn County, Montana. Operated by U S BUREAU OF RECLAMATION, commissioned 1966.
How YELLOWTAIL compares
With 250 MW of capacity, YELLOWTAIL ranks 5th among the 48 operating power plants Bywatts maps in Montana and 4th of the 21 operating Hydro plants in the state. It accounts for about 9.7% of Montana's operating Hydro capacity and 4.0% of all operating capacity in the state. Nationally it is the 75th-largest of the 1,243 operating Hydro plants in the database. Commissioned in 1966, it is older than 67% of the 46 operating Montana plants with a recorded commissioning year. Its operator, U S BUREAU OF RECLAMATION, runs 3 operating plants in Montana totaling 728 MW. It shares Big Horn County with one other operating plant, HARDIN GENERATOR PROJECT.
EIA-860 lists 4 generators at the site with 278 MW of nameplate capacity, all conventional hydroelectric technology (this page's HIFLD capacity figure is 250 MW). Net generation was 798 GWh in 2024 (a 33% capacity factor), up 16% from 2022.
Grid neighborhood
The closest transmission line found within 10 miles is a 230 kV line owned by WAPA-- WESTERN AREA POWER ADMINISTRATION, under 0.1 miles away. Within 50 miles are 2 mapped data centers; the nearest is YRIX in Billings, about 42.3 miles away.
Computed by Bywatts from HIFLD power plant and transmission line records, EIA-860/923 survey data and PeeringDB data center locations; distances are straight-line. Sources and methodology
Weather peril exposure
YELLOWTAIL is a 250 MW hydro power plant in Big Horn County, MT, operated by U S BUREAU OF RECLAMATION, commissioned in 1966. Big Horn County carries elevated modeled catastrophe exposure in the FEMA National Risk Index, scoring 3.2 of 5 at the 56th national percentile. Wildfire is the leading peril, rated Relatively Moderate by FEMA at the 97th 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.
Big Horn County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Wildfire | Relatively Moderate | 97th | 4.9 of 5 | <0.01 |
| Riverine flooding | Relatively Low | 84th | 4.4 of 5 | 0.68 |
| Hail | Relatively Low | 62nd | 3.5 of 5 | 1.6 |
| Heat wave | Very Low | 49th | 3.0 of 5 | 2.0 |
| Earthquake | Very Low | 44th | 2.8 of 5 | <0.01 |
| Lightning | Relatively High | 28th | 2.1 of 5 | 32.4 |
| Ice storm | Very Low | 21st | 1.8 of 5 | 0.01 |
| Winter weather | Relatively High | 18th | 1.7 of 5 | 24.4 |
| Tornado | Very Low | 16th | 1.6 of 5 | 0.32 |
| Strong wind | Relatively High | 7th | 1.3 of 5 | 0.83 |
Perils not assessed in Big Horn 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 |
Model hail, wind and flood exposure for Big Horn 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.