Island County, Washington Natural Disaster Risk
FEMA National Risk Index assessment · WA
LowComposite Risk Score
National percentile: 78th
Island County faces low composite natural disaster risk (NRI Risk Index score 78.0, 78th national percentile), driven primarily by landslide and earthquake exposure. Expected annual loss across all 18 hazard types is $39M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Island County at low composite risk, with a National Risk Index score of 78.0 out of 100 — placing it in the 78th national percentile and below the national average for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
The county's risk is driven primarily by landslide (downhill movement of rock, soil, and debris on unstable slopes) at High risk — $6M in expected annual loss and about 0.40 events per year; earthquake (ground shaking from sudden movement along geologic faults) at Medium risk — $22M in expected annual loss and about 0.03 events per year; and volcanic activity (eruptions producing ashfall, lava, and pyroclastic hazards) at Low risk — $3K in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $39M in expected annual loss for a population of 87K.
Beyond physical exposure, Island County has a low social vulnerability rating (how susceptible the population is to harm) and a very high community resilience rating (its capacity to prepare for and recover from disasters). A less vulnerable population paired with strong resilience helps the community absorb and recover from events.
The federal record bears this out: Island County has received 22 federal disaster declarations since 1980, including 12 for severe storm events and 5 for flood events. The most recent was Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides (flood), declared in April 2026.
Among 39 Washington counties, Island County ranks #21 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Landslide | High | 0.40 / yr | $6M |
| Earthquake | Medium | 0.03 / yr | $22M |
| Volcanic Activity | Low | 0.00 / yr | $3K |
| Ice Storm | Medium | 0.34 / yr | $314K |
| Coastal Flood | Medium | 3.20 / yr | $1M |
| Riverine Flood | Low | 0.04 / yr | $8M |
| Cold Wave | Low | 0.16 / yr | $889K |
| Winter Weather | Low | 5.71 / yr | $56K |
| Tsunami | Very Low | 0.06 / yr | $402K |
| Wildfire | Very Low | 0.00 / yr | $20K |
| Heat Wave | Very Low | 0.48 / yr | $137K |
| Lightning | Low | 4.83 / yr | $88K |
| Tornado | Very Low | 0.01 / yr | $85K |
| Avalanche | Very Low | 0.01 / yr | $2 |
| Hail | Very Low | 0.01 / yr | $3K |
| Strong Wind | Very Low | 0.01 / yr | $6K |
| Drought | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
Disaster History
Island County has received 22 federal disaster declarations since 1980, most recently Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides in April 2026. Most frequent causes: Severe Storm (12), Flood (5), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2026 | Flood | Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| April 2024 | Severe Storm | Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| January 2023 | Severe Storm | Severe Winter Storm, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| January 2022 | Flood | Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| April 2021 | Severe Storm | Severe Winter Storm, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| April 2020 | Flood | Severe Storms, Flooding, Landslides, and Mudslides |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| March 2019 | Severe Storm | Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, Mudslides, Tornado |
| January 2016 | Severe Storm | Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
Showing the 10 most recent of 22 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Island County?
Island County has a composite FEMA National Risk Index score of 78.0 out of 100, placing it in the Low category and the 78th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Island County?
The three highest-rated hazards are Landslide (High, $6M EAL), Earthquake (Medium, $22M EAL), Volcanic Activity (Low, $3K EAL). These account for most of the county's expected annual losses.
How does Island County compare to other Washington counties?
Island County ranks #21 of 39 Washington counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Island County had?
FEMA records 22 federal disaster declarations for Island County since 1980, most often 12 for severe storm events and 5 for flood events. The most recent was Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides, declared in April 2026.
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. Island County's $39M EAL is a statistical average, not a guarantee for any specific year or address.