Oregon volcanic activity risk
Deschutes County has the highest volcanic activity risk in Oregon, scoring 96.1 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Deschutes County | 96.1 | Relatively Moderate |
| 2 | Clackamas County | 95.8 | Relatively Moderate |
| 3 | Hood River County | 95.4 | Relatively Moderate |
| 4 | Lane County | 94.5 | Relatively Moderate |
| 5 | Multnomah County | 93.5 | Relatively Moderate |
| 6 | Marion County | 92.8 | Relatively Moderate |
| 7 | Linn County | 91.9 | Relatively Low |
| 8 | Klamath County | 91.5 | Relatively Low |
| 9 | Wasco County | 91.2 | Relatively Low |
| 10 | Washington County | 89.3 | Relatively Low |
| 11 | Jefferson County | 87.6 | Relatively Low |
| 12 | Douglas County | 85.3 | Relatively Low |
| 13 | Yamhill County | 84.4 | Relatively Low |
| 14 | Polk County | 84 | Very Low |
| 15 | Lincoln County | 83.7 | Very Low |
| 16 | Clatsop County | 82.1 | Very Low |
| 17 | Columbia County | 81.8 | Very Low |
| 18 | Tillamook County | 80.5 | Very Low |
| 19 | Jackson County | 77.5 | Very Low |
| 20 | Lake County | 76.5 | Very Low |
| 21 | Sherman County | 74.6 | Very Low |
| 22 | Harney County | 72.6 | Very Low |
| 23 | Umatilla County | 72 | Very Low |
| 24 | Crook County | 70.4 | Very Low |
| 25 | Morrow County | 63.2 | Very Low |
| 26 | Grant County | 53.1 | Very Low |
| 27 | Malheur County | 52.8 | Very Low |
| 28 | Gilliam County | 51.1 | Very Low |
| 29 | Wheeler County | 44.3 | Very Low |
| 30 | Benton County | 21.5 | Very Low |
| 31 | Baker County | 19.2 | Very Low |
| 32 | Josephine County | 12.4 | Very Low |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Volcanic Activity risk nationally:
Other hazard risks in Oregon:
Frequently asked questions
What is the highest volcanic activity risk county in Oregon?
Deschutes County, OR has the highest volcanic activity risk in Oregon, with a FEMA National Risk Index score of 96.1 out of 100 (rated "Relatively Moderate").
What causes volcanic activity risk in Oregon?
Volcanic activity risk reflects expected losses from lava flows, tephra fall, lahars (volcanic mudflows), and volcanic gases. The highest-risk counties are in Washington (Mt. Rainier), Oregon (Mt. Hood), and Hawaii (Kilauea, Mauna Loa). Alaska's Aleutian chain contains many active volcanoes affecting nearby communities and trans-Pacific air traffic. Volcanic ashfall events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.