Johnson County Disaster Risk

Johnson County has a FEMA National Risk Index rating of Relatively Low, placing it in the 51th 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.

Johnson County is evaluated for five major natural hazard types: earthquake (91th percentile), tornado (56th percentile), hurricane (38th percentile), flooding (38th percentile), wildfire (11th percentile). The highest-risk hazard is earthquake at the 91th 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.

Johnson County's composite risk percentile is 51th, compared to the Illinois state average of 55th percentile. The state's overall risk rating is Relatively Low. This means Johnson County faces lower natural disaster risk than the typical county in Illinois.

Yes, Johnson County's earthquake risk is at the 91th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Johnson County is at the 38th percentile.

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.

Johnson County's composite risk score of 51th percentile is below the Illinois state average of 55th percentile, indicating relatively lower exposure to natural hazards. However, no county is completely risk-free. The primary hazard type is earthquake at the 91th percentile. Residents should still maintain emergency preparedness plans and appropriate insurance coverage.