CHIEF JOSEPH

Operating

Hydro power plant

Capacity
2,456 MW
Primary fuel
Hydro
County
Douglas County
Operator
USACE NORTHWESTERN DIVISION
Status
Operating
Commissioned
1955
EIA plant ID
3921
Coordinates
47.9954, -119.6412

See it on the map

CHIEF JOSEPH, a 2,456 MW Hydro power plant in Douglas County, Washington. Operated by USACE NORTHWESTERN DIVISION, commissioned 1955.

Weather peril exposure

CHIEF JOSEPH is a 2,456 MW hydro power plant in Douglas County, WA, operated by USACE NORTHWESTERN DIVISION, commissioned in 1955. Douglas County carries low modeled catastrophe exposure in the FEMA National Risk Index, scoring 1.6 of 5 at the 14th national percentile. Riverine flooding 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.

1.6 of 5Modeled catastrophe exposure
LowExposure band
Riverine floodingLeading peril
Relatively LowFEMA county risk rating

Douglas County hazard ratings

PerilFEMA ratingNational percentilePeril scoreEvents per year
Riverine floodingRelatively Moderate97th4.9 of 50.32
WildfireRelatively Moderate96th4.9 of 50.01
EarthquakeRelatively Low86th4.4 of 5<0.01
Heat waveRelatively Low63rd3.5 of 54.4
Winter weatherRelatively Low36th2.4 of 514.6
Strong windRelatively Low9th1.3 of 50.11
LightningRelatively Low7th1.3 of 511.5
TornadoVery Low4th1.2 of 50.05
HailRelatively Low2nd1.1 of 50.11
Ice stormVery Low0th1.0 of 50.01

Perils not assessed in Douglas 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.

PerilWhy it is not scored
HurricaneFEMA rating is "Not Applicable" for this county
Coastal floodingFEMA rating is "Not Applicable" for this county

Model hail, wind and flood exposure for Douglas 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.