Delaware County, OH
FEMA National Risk Index scores, disaster declarations & hazard data
Delaware County has experienced 15 federally declared disasters since 1965, most recently Tornadoes in 2024. Its overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Delaware County's highest-rated hazards are hail, winter weather, and ice storm, with its top risk rated "Relatively Moderate" by FEMA's National Risk Index. Recorded storm events have decreased 64% over the past five years compared to the prior five-year period. Community vulnerability is relatively low (2nd percentile nationally), indicating stronger recovery capacity than most US counties.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Delaware County has been designated in 15 declarations since 1965, covering 5 disaster types including severe storm (6), tornado (3), snowstorm (3).
| Year | Type | Event name |
|---|---|---|
| 2024 | Tornado | Tornadoes |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2012 | Severe Storm | Severe Storms |
| 2009 | Severe Storm | Severe Wind Storm Associated With Tropical Depression Ike |
| 2008 | Snowstorm | Record Snow And Near Record Snow |
| 2005 | Snowstorm | Snow |
| 2005 | Severe Storm | Severe Winter Storms, Flooding, And Mudslides |
| 2005 | Hurricane | Hurricane Katrina Evacuation |
| 2004 | Severe Storm | Severe Storms And Flooding |
Showing the 10 most recent of 15 total declarations since 1965.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Very Low | 26.7 | 0 | 0 | — |
| Inland Flooding | Relatively Moderate | 86.4 | 33 | 0 | $11K |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 66.2 | — | — | — |
| Heat Wave | Relatively Low | 76.6 | 2 | 0 | — |
| Tornado | Relatively Moderate | 81.5 | 6 | 0 | $1.1M |
| Hurricane | Very Low | 27.3 | 0 | 0 | — |
| Hail | Relatively Moderate | 89.4 | 13 | 0 | $1K |
| Strong Wind | Relatively Moderate | 78.3 | 0 | 0 | — |
| Winter Weather | Relatively High | 87.8 | 0 | 0 | — |
| Ice Storm | Relatively High | 86.8 | — | — | — |
| Cold Wave | Relatively Low | 40.9 | — | — | — |
| Lightning | Relatively Moderate | 79.6 | 0 | 0 | — |
| Drought | Very Low | 14.4 | 0 | 0 | — |
| Landslide | Very Low | 47.2 | 0 | 0 | — |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Not Applicable | — | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Delaware County ranks in the 2nd percentile (Very low) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 2nd | Very low |
| Socioeconomic status | 1st | Very low |
| Household characteristics | 17th | Very low |
| Racial & ethnic minority status | 50th | Moderate |
| Housing type & transportation | 4th | Very low |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 6th | Very Low |
| Risk to homes | 5th | Very Low |
| Buildings in direct exposure zone | 41.5% | — |
NOAA tracked 53 weather events in this county over 2016–2025: 39 in 2016–20 vs 14 in 2021–25 (-64% — frequency decreasing).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Delaware County?
According to the FEMA National Risk Index, the highest-risk hazards in Delaware County, Ohio are hail, winter weather, and ice storm. The county's overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Has Delaware County received federal disaster declarations?
Yes. Delaware County has received 15 federal disaster declarations since 1965, including declarations in 2024. The most common disaster type on record is severe storm (6 declarations).
Has Delaware County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Delaware County include Tornadoes (2024). See the declarations table above for the full history since 1965.
How does Delaware County's natural hazard risk compare to nearby counties?
Among neighboring counties, Franklin County, OH has the highest overall natural hazard risk (Relatively High) and Morrow County, OH has the lowest (Very Low). Delaware County is rated Relatively Low overall.
How is Delaware County's composite disaster risk index calculated?
Delaware County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Delaware County's composite score of 79 means its overall natural hazard risk is higher than 79% of US counties.