ROSS
OperatingHydro power plant
- Capacity
- 450 MW
- Primary fuel
- Hydro
- County
- Whatcom County
- Operator
- CITY OF SEATTLE - (WA)
- Status
- Operating
- Commissioned
- 1952
- EIA plant ID
- 6202
- Generators
- 4
- Technology
- Conventional Hydroelectric
- Net generation (2024)
- 410 GWh
- Capacity factor (2024, EIA nameplate)
- 10%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 48.7299, -121.0713
ROSS, a 450 MW Hydro power plant in Whatcom County, Washington. Operated by CITY OF SEATTLE - (WA), commissioned 1952.
How ROSS compares
With 450 MW of capacity, ROSS ranks 17th among the 126 operating power plants Bywatts maps in Washington and 13th of the 65 operating Hydro plants in the state. It accounts for about 2.1% of Washington's operating Hydro capacity and 1.5% of all operating capacity in the state. Nationally it is the 50th-largest of the 1,243 operating Hydro plants in the database. Commissioned in 1952, it is older than 80% of the 125 operating Washington plants with a recorded commissioning year. Its operator, CITY OF SEATTLE - (WA), runs 7 operating plants in Washington totaling 1,929 MW. It shares Whatcom County with 9 other operating plants, including FERNDALE GENERATING STATION and GORGE.
EIA-860 lists 4 generators at the site with 450 MW of nameplate capacity, all conventional hydroelectric technology. Net generation was 410 GWh in 2024 (a 10% capacity factor), down 45% from 2022. Its generators came online between 1952 and 1956.
Grid neighborhood
The nearest named substation is DIABLO (230 kV), about 3.4 miles away; the closest transmission line found within 10 miles is a 230 kV line owned by CITY OF SEATTLE - (WA), under 0.1 miles away. Another 3 operating power plants totaling 392 MW sit within 25 miles; the largest is GORGE (207 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
ROSS is a 450 MW hydro power plant in Whatcom County, WA, operated by CITY OF SEATTLE - (WA), commissioned in 1952. Whatcom County carries low modeled catastrophe exposure in the FEMA National Risk Index, scoring 1.1 of 5 at the 2nd national percentile. Earthquake is the leading peril, rated Relatively Moderate by FEMA at the 95th 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.
Whatcom County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Earthquake | Relatively Moderate | 95th | 4.8 of 5 | 0.02 |
| Coastal flooding | Relatively Moderate | 56th | 3.2 of 5 | 3.6 |
| Heat wave | Relatively Moderate | 49th | 3.0 of 5 | 2.4 |
| Riverine flooding | Relatively Moderate | 46th | 2.9 of 5 | 0.18 |
| Winter weather | Relatively Moderate | 34th | 2.4 of 5 | 37.3 |
| Ice storm | Very High | 32nd | 2.3 of 5 | 0.53 |
| Wildfire | Very Low | 29th | 2.2 of 5 | <0.01 |
| Lightning | Relatively Moderate | 4th | 1.2 of 5 | 8.1 |
| Tornado | Very Low | 3rd | 1.1 of 5 | 0.02 |
| Hail | Very Low | 1st | 1.0 of 5 | 0.01 |
| Strong wind | Very Low | 0th | 1.0 of 5 | <0.01 |
Perils not assessed in Whatcom 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 |
Model hail, wind and flood exposure for Whatcom 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.