NOXON RAPIDS
OperatingHydro power plant
- Capacity
- 532 MW
- Primary fuel
- Hydro
- County
- Sanders County
- Operator
- AVISTA CORP
- Status
- Operating
- Commissioned
- 1959
- EIA plant ID
- 2199
- Generators
- 5
- Technology
- Conventional Hydroelectric
- Net generation (2024)
- 1,324 GWh
- Capacity factor (2024, EIA nameplate)
- 31%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 47.9607, -115.7342
NOXON RAPIDS, a 532 MW Hydro power plant in Sanders County, Montana. Operated by AVISTA CORP, commissioned 1959.
How NOXON RAPIDS compares
With 532 MW of capacity, NOXON RAPIDS ranks 2nd among the 48 operating power plants Bywatts maps in Montana and is the largest of the 21 operating Hydro plants in the state. It accounts for about 21% of Montana's operating Hydro capacity and 8.6% of all operating capacity in the state. Nationally it is the 42nd-largest of the 1,243 operating Hydro plants in the database. Commissioned in 1959, it is older than 69% of the 46 operating Montana plants with a recorded commissioning year. It shares Sanders County with one other operating plant, THOMPSON FALLS.
EIA-860 lists 5 generators at the site with 488 MW of nameplate capacity, all conventional hydroelectric technology. Net generation was 1,324 GWh in 2024 (a 31% capacity factor), down 24% from 2022. Its generators came online between 1959 and 1977.
Grid neighborhood
The nearest named substation is NOXON (230 kV), about 0.2 miles away; the closest transmission line found within 10 miles is a 230 kV line owned by AVISTA CORP, under 0.1 miles away. One other operating power plant sits within 25 miles: CABINET GORGE (265 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
NOXON RAPIDS is a 532 MW hydro power plant in Sanders County, MT, operated by AVISTA CORP, commissioned in 1959. Sanders County carries low modeled catastrophe exposure in the FEMA National Risk Index, scoring 1.4 of 5 at the 10th national percentile. Riverine flooding is the leading peril, rated Relatively Low by FEMA at the 93rd 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.
Sanders County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Riverine flooding | Relatively Low | 93rd | 4.7 of 5 | 0.68 |
| Ice storm | Relatively Moderate | 88th | 4.5 of 5 | 0.20 |
| Wildfire | Relatively Moderate | 87th | 4.5 of 5 | <0.01 |
| Earthquake | Relatively Low | 81st | 4.2 of 5 | 0.02 |
| Winter weather | Relatively High | 70th | 3.8 of 5 | 43.6 |
| Heat wave | Very Low | 48th | 2.9 of 5 | 2.1 |
| Strong wind | Very Low | 14th | 1.6 of 5 | 0.22 |
| Lightning | Very Low | 13th | 1.5 of 5 | 17.8 |
| Hail | Very Low | 12th | 1.5 of 5 | 0.30 |
| Tornado | Very Low | 3rd | 1.1 of 5 | 0.04 |
Perils not assessed in Sanders 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 Sanders 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.