FloodZoneMap.org

Union County, Ohio Flood Zones

Check an Address in Union County

Enter any address in Union County, Ohio to see its FEMA flood zone

The Flooding Character of Union County

Flash flooding from thunderstorms is the dominant flood character in Union County, OH. Over the past 30 years, NOAA Storm Events data recorded 44 flood events and 15 flash flood events. Recent examples include flash flooding on June 5, 2024, attributed to a cold front causing heavy rain, and widespread showers leading to flooding on July 6, 2022.

National Flood Insurance Program (NFIP) claims data shows that properties in Zone A experienced an average water depth of 2.7 feet, with an average payout of $8,724. Properties in Zone X had an average water depth of 0.3 feet and an average payout of $9,392. Homeowners in or near areas designated as Zone A, or those located near rivers and streams, should pay the most attention to flood risk.

Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.

Read First-Hand Flood Stories from Union County

1 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.

Read Ohio flood stories →

Flood Risk Data for Union County

Union County, Ohio has recorded 59 flood-related events since 1996 according to NOAA's Storm Events Database, including 15 flash floods and 44 river or area floods. The county has received 13 federal disaster declarations. Enter any address above to check its FEMA flood zone designation.

Union County Disaster History

FEMA Disaster Declarations (1978–2024)

Disaster Declarations
13
Latest Disaster
Tornadoes (2024-03-14)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Union County

DeclarationTypeDate
TornadoesTornadoMar 14, 2024
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Severe StormsSevere StormJun 29, 2012
Severe Wind Storm Associated With Tropical Depression IkeSevere StormSep 14, 2008
Record Snow And Near Record SnowSnowstormMar 7, 2008
Hurricane Katrina EvacuationHurricaneAug 29, 2005
Severe Winter Storms, Flooding, And MudslidesSevere StormDec 22, 2004
SnowSnowstormDec 22, 2004
Severe Storms And FloodingSevere StormAug 27, 2004

Recorded Flood Events in Union County

NOAA Storm Events Database (1996–2025)

Total Flood Events
59
River/Area Floods
44
Flash Floods
15
Total Property Damage
$3.1M

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Union County

TypeDateDamage
Flash FloodJun 5, 20240.00K
FloodJul 24, 20230.00K
FloodJul 17, 20220.00K
FloodJul 6, 20220.00K
FloodJun 10, 20210.00K
FloodMar 28, 20200.00K
FloodSep 7, 20200.00K
FloodJun 19, 20190.00K
FloodJun 18, 20190.00K
FloodMay 17, 20190.00K

Union County Flood History

Flash Flood — Jun 5, 2024

A cold front moved through the Ohio Valley, causing showers and thunderstorms out ahead of it. Some of the storms produced heavy rain and flash flooding.

Flood — Jul 24, 2023

Scattered thunderstorms developed as a low pressure system moved through the Ohio Valley.

Flood — Jul 17, 2022

Showers with embedded thunderstorms developed ahead of a low pressure system moving through the Great Lakes region.

Flood — Jul 6, 2022

An upper level disturbance produced widespread showers and thunderstorms across central Ohio during the overnight hours.

Flood — Jun 10, 2021

Slow moving thunderstorms developed during the afternoon hours in a warm and humid airmass.

Source: NOAA National Weather Service Storm Events Database.

Union County NFIP Flood Insurance Claims

Total Claims Filed
47
Total Paid Out
$367,853
Avg Claim
$9,680
Avg Water Depth
3.7 ft

Claims by Flood Zone

A Zones (High Risk)
22
X Unshaded (Low)
2

Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).

Flood Zone Types in Union County

FEMA assigns flood zone designations to areas in Union County, Ohio:

AE High Risk — 1% annual chance of flooding. Insurance required.

VE Very High Risk — Coastal flooding with wave action.

X (Shaded) Moderate Risk — 500-year floodplain.

X Low Risk — Outside major floodplains.

View all flood zone types →

Flood Insurance in Union County

Properties in Union County, Ohio that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.

Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.

Visit FloodSmart.gov to find an agent and get a quote.