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

Union County Disaster Risk

Union County, Illinois

FEMA Risk Rating

Relatively Low

National Percentile

55th

of 3,144 counties

State Rank

#50

of 102 (1 = highest risk)

Flood Risk

39th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 39% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 9% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 62% of US counties

Earthquake

Seismic activity and ground shaking risk

Moderate

Higher than 90% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 36% of US counties

Risk Overview

About Natural Disaster Risk in Union County, Illinois

Union County near national risk average

With a composite risk score of 55.38, Union County sits just above the national median for natural disaster risk. This "Relatively Low" rating masks significant earthquake exposure (90.14), which is exceptionally high despite moderate overall risk.

Slightly below Illinois average

Union's 55.38 score edges slightly below the Illinois state average of 54.46, making it one of the safer counties statewide. However, its earthquake risk places it among the state's most seismically vulnerable counties.

Similar risk to Washington County

Union County's 55.38 score closely mirrors nearby Washington County (55.15), both sitting in the lower-risk zone. Both counties share elevated earthquake exposure that distinguishes them from lower-risk peers like Wabash County (24.84).

Earthquake risk dominates the profile

Earthquake risk of 90.14 is exceptionally high and Union's primary hazard concern, reflecting its position near active fault zones in southern Illinois. Tornado risk (61.58) and hurricane risk (36.13) present secondary but meaningful threats.

Earthquake coverage is your priority

Standard homeowners insurance excludes earthquake damage—you must purchase a separate earthquake policy to protect your home from seismic events. Secure heavy furniture, water heaters, and mirrors to walls, and keep emergency supplies (water, food, first aid) accessible.

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

Preparedness Guide

What to Prepare for in Union County

Top Hazards by Exposure

  1. #1
    EarthquakePrepare
    90th percentile
  2. #2
    TornadoPrepare
    62th percentile
  3. #3
    FloodPrepare
    39th percentile

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

Risk Advisory: Union County

Risk Verdict

Natural hazard pressure in Union County is below the national midpoint, with a composite score at the 55th percentile. Proactive emergency planning and awareness of the specific hazards driving Union County's score can meaningfully reduce household risk.

Hazard Breakdown

Earthquake risk is Union County's dominant natural hazard, ranked at the 90th percentile nationally under FEMA's National Risk Index. Tornado ranks second at the 62th percentile nationally. Additional tracked hazards include flood (39th percentile), hurricane (36th percentile), wildfire (9th percentile).

Preparedness Context

Earthquake exposure at the 90th percentile nationally puts Union County in a zone where utilities — gas, water, electrical — are the most common post-quake hazard. Knowing how to shut off the main gas valve is an important household skill to develop before an event occurs. Alongside earthquake exposure, Union County's tornado risk at the 62th percentile nationally reinforces the value of maintaining a household emergency supply cache usable for multiple hazard scenarios. Union County households benefit from keeping shoes and a flashlight near the bed — post-earthquake navigation through debris in the dark is a common cause of secondary injury. This low-cost step has outsized protective value.

Regional Context

Union County's risk score is broadly comparable to the Illinois county average, with a 0.9-point gap that places the county near the center of the state's hazard distribution.

Is your household prepared for Union 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 Union County, IL?
Union County has a FEMA National Risk Index rating of Relatively Low, placing it in the 55th 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 Union County?
Union County is evaluated for five major natural hazard types: earthquake (90th percentile), tornado (62th percentile), flooding (39th percentile), hurricane (36th percentile), wildfire (9th percentile). The highest-risk hazard is earthquake at the 90th 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 Union County risk compare to the Illinois average?
Union County's composite risk percentile is 55th, compared to the Illinois state average of 55th percentile. The state's overall risk rating is Relatively Low. This means Union County faces higher natural disaster risk than the typical county in Illinois.
Is Union County at risk for earthquake?
Yes, Union County's earthquake risk is at the 90th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Union County is at the 39th 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 Union County higher risk than average?
Union County's composite risk score of 55th percentile is above the Illinois state average of 55th percentile. This elevated risk is driven by earthquake exposure (90th percentile), along with tornado 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.