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

Polk County Disaster Risk

Polk County, Oregon

FEMA Risk Rating

Relatively Low

National Percentile

73th

of 3,144 counties

State Rank

#20

of 36 (1 = highest risk)

Flood Risk

68th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 68% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 43% of US counties

Tornado

Tornado and severe thunderstorm risk

Very Low

Higher than 13% of US counties

Earthquake

Seismic activity and ground shaking risk

Relatively High

Higher than 95% of US counties

Risk Overview

About Natural Disaster Risk in Polk County, Oregon

Polk County's risk slightly above average

Polk County's composite score of 72.84 and Relatively Low rating exceed the U.S. average but reflect moderate hazard exposure across multiple types. Earthquake risk (95.39) and flood risk (68.23) drive the county's overall profile.

Mid-range risk compared to Oregon

At 72.84, Polk County sits notably above Oregon's 63.43 state average, placing it in the state's upper-middle tier for disaster risk. The Willamette Valley location exposes residents to significant seismic and flood hazards.

Riskier than most adjacent counties

Polk County's 72.84 score exceeds Marion, Benton, and Yamhill counties' composite risks. The county's position in the seismically active Willamette Valley explains its elevated earthquake exposure relative to western neighbors.

Earthquakes and floods threaten Polk

Earthquake risk reaches 95.39, reflecting Polk's location in Oregon's most seismically active region. Flood risk scores 68.23, with the Willamette River and tributaries posing seasonal inundation threats to valley communities.

Earthquakes and flood coverage essential

Polk County homeowners should secure earthquake insurance riders—often 10–15% of home value—and verify flood coverage, particularly if within a mapped floodplain. Standard policies exclude both, making separate coverage critical.

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

Preparedness Guide

What to Prepare for in Polk County

Top Hazards by Exposure

  1. #1
    EarthquakePrepare
    95th percentile
  2. #2
    FloodPrepare
    68th percentile
  3. #3
    WildfirePrepare
    43th percentile

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

Risk Advisory: Polk County

Risk Verdict

At the 73th percentile nationally, Polk County experiences a manageable level of natural hazard risk that falls below the U.S. median. Polk County's risk profile calls for targeted preparedness, focusing on the hazard categories that dominate the county's score.

Hazard Breakdown

Earthquake risk is Polk County's dominant natural hazard, ranked at the 95th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 68th percentile nationally. Additional tracked hazards include wildfire (43th percentile), tornado (13th percentile).

Preparedness Context

Polk County's primary hazard, earthquake, ranks at the 95th percentile nationally. Unreinforced masonry structures carry the highest injury risk during seismic events; residents in older buildings should check with their municipality about available seismic retrofit programs. The county's flood risk at the 68th percentile nationally is a seasonal consideration alongside the year-round earthquake threat, requiring awareness of both hazard types. After a major earthquake, Polk County residents should expect water service disruption for 24 to 72 or more hours. Storing a minimum of one gallon per person per day for three days — before any event — is the most direct preparedness action households can take.

Regional Context

Polk County falls 9.4 points above Oregon's typical county risk level, which means the hazard environment here is notably more demanding than the state baseline.

Is your household prepared for Polk 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 Polk County, OR?
Polk County has a FEMA National Risk Index rating of Relatively Low, placing it in the 73th 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 Polk County?
Polk County is evaluated for five major natural hazard types: earthquake (95th percentile), flooding (68th percentile), wildfire (43th percentile), tornado (13th percentile). The highest-risk hazard is earthquake at the 95th 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 Polk County risk compare to the Oregon average?
Polk County's composite risk percentile is 73th, compared to the Oregon state average of 63th percentile. The state's overall risk rating is Relatively Low. This means Polk County faces higher natural disaster risk than the typical county in Oregon.
Is Polk County at risk for earthquake?
Yes, Polk County's earthquake risk is at the 95th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Polk County is at the 68th 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 Polk County higher risk than average?
Polk County's composite risk score of 73th percentile is above the Oregon state average of 63th percentile. This elevated risk is driven by earthquake exposure (95th 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.