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

Delaware County Disaster Risk

Delaware County, Ohio

FEMA Risk Rating

Relatively Low

National Percentile

79th

of 3,144 counties

State Rank

#13

of 88 (1 = highest risk)

Flood Risk

86th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Moderate

Higher than 86% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 27% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 82% of US counties

Earthquake

Seismic activity and ground shaking risk

Relatively Low

Higher than 66% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 27% of US counties

Risk Overview

About Natural Disaster Risk in Delaware County, Ohio

Delaware County faces elevated disaster risk

Delaware County scores 78.75 on the composite risk scale, earning a 'Relatively Low' rating that nonetheless exceeds national averages substantially. The county's composite score reflects significant exposure across multiple natural disaster categories.

High-risk county within Ohio

At 78.75, Delaware County's risk score substantially exceeds Ohio's state average of 55.03, placing it in the upper tier of the state's most hazard-prone counties. The county's composite risk is roughly 43% above the statewide average.

Regional risk leader among peers

Delaware County (78.75) faces considerably higher disaster risk than most nearby counties, including Crawford (35.24), Defiance (41.89), and Darke (52.67). Only Fairfield County (72.61) approaches comparable risk levels among surrounding communities.

Floods and tornadoes demand preparedness

Flood risk (86.36) and tornado risk (81.52) dominate Delaware County's natural disaster profile, both scoring in the high range. Earthquake risk (66.19) ranks third among county hazards, while wildfire (26.75) and hurricane (27.28) risks remain secondary concerns.

Invest in comprehensive flood and tornado protection

Delaware County residents should prioritize flood insurance and storm-rated safe rooms, given the county's elevated flood and tornado risks. Ensure proper drainage around foundations, install storm shutters, and secure a backup generator for extended power outages following severe weather events.

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

Preparedness Guide

What to Prepare for in Delaware County

Top Hazards by Exposure

  1. #1
    FloodPrepare
    86th percentile
  2. #2
    TornadoPrepare
    82th percentile
  3. #3
    EarthquakePrepare
    66th percentile

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

Risk Advisory: Delaware County

Risk Verdict

Delaware County ranks at the 79th percentile nationally for natural disaster risk — below the median for U.S. counties. Comprehensive household preparedness — including reviewing insurance, maintaining emergency supplies, and knowing evacuation routes — is strongly recommended.

Hazard Breakdown

Flood risk is Delaware County's dominant natural hazard, ranked at the 86th percentile nationally under FEMA's National Risk Index. Tornado ranks second at the 82th percentile nationally. Additional tracked hazards include earthquake (66th percentile), hurricane (27th percentile), wildfire (27th percentile).

Preparedness Context

Delaware County sits at the 86th percentile nationally for flood exposure. Knowing your property's flood zone designation — available at FEMA's Flood Map Service Center — is the first step toward understanding actual exposure and insurance options. Secondary tornado exposure at the 82th percentile adds a second preparedness layer; households should review coverage options and alert sign-up for both hazard types. Regardless of specific hazard, Delaware County households benefit from a practiced communication plan: a designated out-of-state contact and a pre-agreed evacuation destination established before the season's peak risk period.

Regional Context

Compared to other Ohio counties, Delaware County runs 23.7 composite risk points higher than the state mean — reflecting above-average hazard concentration in this area.

Is your household prepared for Delaware 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 Delaware County, OH?
Delaware County has a FEMA National Risk Index rating of Relatively Low, placing it in the 79th 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 Delaware County?
Delaware County is evaluated for five major natural hazard types: flooding (86th percentile), tornado (82th percentile), earthquake (66th percentile), hurricane (27th percentile), wildfire (27th percentile). The highest-risk hazard is flooding at the 86th 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 Delaware County risk compare to the Ohio average?
Delaware County's composite risk percentile is 79th, compared to the Ohio state average of 55th percentile. The state's overall risk rating is Relatively Low. This means Delaware County faces higher natural disaster risk than the typical county in Ohio.
Is Delaware County at risk for flooding?
Yes, Delaware County's flooding risk is at the 86th percentile nationally. This places it in the top quartile for this hazard type.
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 Delaware County higher risk than average?
Delaware County's composite risk score of 79th percentile is above the Ohio state average of 55th percentile. This elevated risk is driven by flooding exposure (86th percentile), along with tornado and earthquake 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.