Iroquois County, Illinois Natural Disaster Risk
FEMA National Risk Index assessment · IL
LowComposite Risk Score
National percentile: 74th
Iroquois County faces low composite natural disaster risk (NRI Risk Index score 74.0, 74th national percentile), driven primarily by cold wave and riverine flood exposure. Expected annual loss across all 18 hazard types is $34M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Iroquois County is low, with a National Risk Index score of 74.0 out of 100 — placing it in the 74th national percentile and below the national average for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in cold wave (prolonged spells of dangerously low temperatures) at High risk — $10M in expected annual loss and about 3.63 events per year; riverine flood (rivers and streams overflowing their banks after heavy rain or snowmelt) at Medium risk — $20M in expected annual loss and about 1.39 events per year; and earthquake (ground shaking from sudden movement along geologic faults) at Low risk — $891K in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $34M in expected annual loss for a population of 27K.
Beyond physical exposure, Iroquois County has a low social vulnerability rating (how susceptible the population is to harm) and a high community resilience rating (its capacity to prepare for and recover from disasters). A less vulnerable population paired with strong resilience helps the community absorb and recover from events.
History supports the rating: Iroquois County has received 9 federal disaster declarations since 1990, including 2 for biological events and 2 for severe storm events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 102 Illinois counties, Iroquois County ranks #29 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | High | 3.63 / yr | $10M |
| Riverine Flood | Medium | 1.39 / yr | $20M |
| Earthquake | Low | 0.00 / yr | $891K |
| Hail | Low | 3.09 / yr | $508K |
| Tornado | Low | 1.02 / yr | $2M |
| Strong Wind | Low | 4.62 / yr | $514K |
| Heat Wave | Low | 4.74 / yr | $289K |
| Landslide | Very Low | 0.18 / yr | $610 |
| Lightning | Low | 45.80 / yr | $128K |
| Hurricane | Very Low | 0.01 / yr | $15K |
| Winter Weather | Low | 9.95 / yr | $27K |
| Ice Storm | Very Low | 0.98 / yr | $26K |
| Drought | Very Low | 0.25 / yr | $8K |
| Wildfire | Very Low | 0.00 / yr | $1K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Iroquois County has received 9 federal disaster declarations since 1990, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Biological (2), Severe Storm (2), Snowstorm (2).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| March 2008 | Severe Storm | Severe Storms and Flooding |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| May 2002 | Tornado | Severe Storms, Tornadoes and Flooding |
| January 2001 | Snowstorm | Illinois Winter Snow Storms |
| January 1999 | Snowstorm | Il-Winter Storm 1/1/99 |
| April 1994 | Severe Storm | Severe Storms and Flooding |
| March 1990 | Severe Ice Storm | Severe Ice Storm |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Iroquois County?
Iroquois County has a composite FEMA National Risk Index score of 74.0 out of 100, placing it in the Low category and the 74th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Iroquois County?
The three highest-rated hazards are Cold Wave (High, $10M EAL), Riverine Flood (Medium, $20M EAL), Earthquake (Low, $891K EAL). These account for most of the county's expected annual losses.
How does Iroquois County compare to other Illinois counties?
Iroquois County ranks #29 of 102 Illinois counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Iroquois County had?
FEMA records 9 federal disaster declarations for Iroquois County since 1990, most often 2 for biological events and 2 for severe storm events. The most recent was Covid-19 Pandemic, declared in March 2020.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Iroquois County's $34M EAL is a statistical average, not a guarantee for any specific year or address.