riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Island County Disaster Risk

Island County, Washington

FEMA Risk Rating

Relatively Low

National Percentile

78th

of 3,144 counties

State Rank

#21

of 39 (1 = highest risk)

Flood Risk

73th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 73% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 35% of US counties

Tornado

Tornado and severe thunderstorm risk

Very Low

Higher than 11% of US counties

Earthquake

Seismic activity and ground shaking risk

Relatively High

Higher than 96% of US counties

Risk Overview

About Natural Disaster Risk in Island County, Washington

Island County's Natural Disaster Risk

Island County scores 77.99 on the composite risk scale, earning a Relatively Low rating but exceeding Washington's state average of 70.01. The county's island geography creates focused exposure to seismic and flood hazards despite lower wildfire risk.

Where Island Ranks in Washington

Island County ranks in the mid-to-upper range among Washington's 39 counties for natural disaster risk, with a score of 77.99. The county's risk profile is heavily shaped by its Puget Sound location and proximity to major fault systems.

Compared to Your Neighbors

Island County's risk (77.99) exceeds inland peer Grant County (76.94) but significantly trails coastal Grays Harbor County (96.98). Unlike Grays Harbor, Island County's lower wildfire risk (35.43) reflects marine climate influence, but earthquake exposure (96.28) remains critically high.

Your Top Threats: Earthquake and Flood

Earthquake risk ranks highest at 96.28, reflecting Island County's position adjacent to the Puget Sound and active seismic zones underlying Puget Basin geology. Flood risk at 73.40 reflects island and tidal dynamics, while wildfire exposure remains low at 35.43 due to the maritime climate.

Earthquake and Flood Coverage Essential

Island County residents should secure earthquake insurance immediately and obtain flood coverage through the National Flood Insurance Program for coastal properties. Retrofit homes to current seismic codes and maintain awareness of tsunami risk in waterfront areas.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Island County

Top Hazards by Exposure

  1. #1
    EarthquakePrepare
    96th percentile
  2. #2
    FloodPrepare
    73th percentile
  3. #3
    WildfirePrepare
    35th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Island County

Risk Verdict

Island County's FEMA risk score places it at the 78th percentile nationally, indicating lower-than-typical exposure for a U.S. county. At this risk level, having a documented household preparedness plan — not just awareness — is the meaningful next step for Island County residents.

Hazard Breakdown

Earthquake risk is Island County's dominant natural hazard, ranked at the 96th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 73th percentile nationally. Additional tracked hazards include wildfire (35th percentile), tornado (11th percentile).

Preparedness Context

With earthquake ranked as the top hazard at the 96th percentile nationally, Island County residents benefit from reviewing homeowners insurance: standard policies rarely cover earthquake damage, and separate earthquake insurance must be purchased before an event. The county's flood risk at the 73th percentile nationally is a seasonal consideration alongside the year-round earthquake threat, requiring awareness of both hazard types. Earthquake insurance in Island County is typically offered as a separate policy — standard homeowners coverage excludes ground movement. Reviewing this gap and comparing policy options before an event is a financial preparedness step with potentially large consequences.

Regional Context

The Washington county average is 8.0 composite points below Island County's score, a gap that reflects the county's elevated position in the state's hazard distribution.

Is your household prepared for Island County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Island County, WA?
Island County has a FEMA National Risk Index rating of Relatively Low, placing it in the 78th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Island County?
Island County is evaluated for five major natural hazard types: earthquake (96th percentile), flooding (73th percentile), wildfire (35th percentile), tornado (11th percentile). The highest-risk hazard is earthquake at the 96th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Island County risk compare to the Washington average?
Island County's composite risk percentile is 78th, compared to the Washington state average of 70th percentile. The state's overall risk rating is Relatively Low. This means Island County faces higher natural disaster risk than the typical county in Washington.
Is Island County at risk for earthquake?
Yes, Island County's earthquake risk is at the 96th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Island County is at the 73th percentile.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Why is Island County higher risk than average?
Island County's composite risk score of 78th percentile is above the Washington state average of 70th percentile. This elevated risk is driven by earthquake exposure (96th percentile), along with flooding risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

Data Source

Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.

Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.