Marion County, Oregon Natural Disaster Risk
FEMA National Risk Index assessment · OR
HighComposite Risk Score
National percentile: 96th
Marion County faces high composite natural disaster risk (NRI Risk Index score 95.5, 96th national percentile), driven primarily by earthquake and heat wave exposure. Expected annual loss across all 18 hazard types is $171M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Marion County at high composite risk, with a National Risk Index score of 95.5 out of 100 — placing it in the 96th national percentile and in the upper tier of natural-disaster risk nationally. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in earthquake (ground shaking from sudden movement along geologic faults) at High risk — $122M in expected annual loss and about 0.02 events per year; heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at Medium risk — $7M in expected annual loss and about 5.62 events per year; and volcanic activity (eruptions producing ashfall, lava, and pyroclastic hazards) at Medium risk — $84K in expected annual loss and about 0.01 events per year. Across all hazards, FEMA estimates $171M in expected annual loss for a population of 344K.
Beyond physical exposure, Marion County has a medium social vulnerability rating (how susceptible the population is to harm) and a medium community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The county's disaster history tells the same story: Marion County has received 15 federal disaster declarations since 1964, including 4 for fire events and 4 for flood events. The most recent was Liberty Fire (fire), declared in August 2023.
Among 36 Oregon counties, Marion County ranks #4 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Earthquake | High | 0.02 / yr | $122M |
| Heat Wave | Medium | 5.62 / yr | $7M |
| Volcanic Activity | Medium | 0.01 / yr | $84K |
| Riverine Flood | Medium | 0.71 / yr | $37M |
| Strong Wind | High | 0.06 / yr | $2M |
| Lightning | High | 7.27 / yr | $986K |
| Landslide | Low | 3.63 / yr | $23K |
| Winter Weather | Medium | 18.44 / yr | $180K |
| Ice Storm | Medium | 0.64 / yr | $245K |
| Wildfire | Very Low | 0.00 / yr | $75K |
| Cold Wave | Low | 0.24 / yr | $932K |
| Hail | Low | 0.13 / yr | $172K |
| Avalanche | Very Low | 0.01 / yr | $122 |
| Tornado | Very Low | 0.10 / yr | $268K |
| Drought | Very Low | 5.77 / yr | $1K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Marion County has received 15 federal disaster declarations since 1964, most recently Liberty Fire in August 2023. Most frequent causes: Fire (4), Flood (4), Severe Storm (3).
| Declared | Type | Disaster |
|---|---|---|
| August 2023 | Fire | Liberty Fire |
| May 2021 | Severe Storm | Severe Winter Storm |
| September 2020 | Fire | Wildfires and Straight-Line Winds |
| September 2020 | Fire | Wildfires |
| September 2020 | Fire | Beachie Creek Lionshead Fire Complex |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| March 2012 | Flood | Severe Winter Storm, Flooding, Landslides, and Mudslides |
| March 2009 | Severe Storm | Severe Winter Storm, Record and Near Record Snow |
| September 2005 | Coastal Storm | Hurricane Katrina Evacuation |
Showing the 10 most recent of 15 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Marion County?
Marion County has a composite FEMA National Risk Index score of 95.5 out of 100, placing it in the High category and the 96th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Marion County?
The three highest-rated hazards are Earthquake (High, $122M EAL), Heat Wave (Medium, $7M EAL), Volcanic Activity (Medium, $84K EAL). These account for most of the county's expected annual losses.
How does Marion County compare to other Oregon counties?
Marion County ranks #4 of 36 Oregon counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Marion County had?
FEMA records 15 federal disaster declarations for Marion County since 1964, most often 4 for fire events and 4 for flood events. The most recent was Liberty Fire, declared in August 2023.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Marion County's $171M EAL is a statistical average, not a guarantee for any specific year or address.