MILNER HYDRO
OperatingHydro power plant
- Capacity
- 60 MW
- Primary fuel
- Hydro
- County
- Cassia County
- Operator
- IDAHO POWER CO
- Status
- Operating
- Commissioned
- 1992
- EIA plant ID
- 7190
- Generators
- 3
- Technology
- Conventional Hydroelectric
- Net generation (2024)
- 98.7 GWh
- Capacity factor (2024, EIA nameplate)
- 19%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 42.5268, -114.0369
MILNER HYDRO, a 60 MW Hydro power plant in Cassia County, Idaho. Operated by IDAHO POWER CO, commissioned 1992.
How MILNER HYDRO compares
With 60 MW of capacity, MILNER HYDRO ranks 20th among the 123 operating power plants Bywatts maps in Idaho and 10th of the 70 operating Hydro plants in the state. It accounts for about 2.4% of Idaho's operating Hydro capacity and 1.2% of all operating capacity in the state. Nationally it is the 256th-largest of the 1,243 operating Hydro plants in the database. Commissioned in 1992, it is newer than 52% of the 121 operating Idaho plants with a recorded commissioning year. Its operator, IDAHO POWER CO, runs 20 operating plants in Idaho totaling 1,894 MW. It shares Cassia County with 4 other operating plants, including MILNER DAM WIND PARK LLC and RAFT RIVER GEOTHERMAL POWER PLANT.
EIA-860 lists 3 generators at the site with 60 MW of nameplate capacity, all conventional hydroelectric technology. Net generation was 98.7 GWh in 2024 (a 19% capacity factor).
Grid neighborhood
The nearest named substation is BYPASS HYDROELECTRIC FACILITY, about 2.5 miles away; the closest transmission line found within 10 miles is a 138 kV line owned by IDAHO POWER CO, under 0.1 miles away. Another 15 operating power plants totaling 174 MW sit within 25 miles; the largest is TWIN FALLS (53 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
MILNER HYDRO is a 60 MW hydro power plant in Cassia County, ID, operated by IDAHO POWER CO, commissioned in 1992. Cassia County carries moderate modeled catastrophe exposure in the FEMA National Risk Index, scoring 2.0 of 5 at the 24th national percentile. Wildfire is the leading peril, rated Relatively Moderate by FEMA at the 99th 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.
Cassia County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Wildfire | Relatively Moderate | 99th | 5.0 of 5 | 0.01 |
| Earthquake | Relatively Low | 81st | 4.3 of 5 | <0.01 |
| Riverine flooding | Relatively Low | 61st | 3.5 of 5 | 0.75 |
| Heat wave | Relatively Low | 53rd | 3.1 of 5 | 2.5 |
| Strong wind | Relatively Low | 37th | 2.5 of 5 | 0.51 |
| Winter weather | Relatively Moderate | 34th | 2.4 of 5 | 15.3 |
| Lightning | Relatively Moderate | 25th | 2.0 of 5 | 28.4 |
| Hail | Very Low | 18th | 1.7 of 5 | 0.30 |
| Ice storm | Very Low | 18th | 1.7 of 5 | 0.01 |
| Tornado | Very Low | 11th | 1.4 of 5 | 0.22 |
Perils not assessed in Cassia 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 Cassia 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.