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

Riverside County Disaster Risk

Riverside County, California

FEMA Risk Rating

Very High

National Percentile

100th

of 3,144 counties

State Rank

#2

of 58 (1 = highest risk)

Flood Risk

100th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very High

Higher than 100% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very High

Higher than 100% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 87% of US counties

Earthquake

Seismic activity and ground shaking risk

Very High

Higher than 100% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 12% of US counties

Risk Overview

About Natural Disaster Risk in Riverside County, California

Riverside ranks among nation's highest-risk counties

With a composite risk score of 99.90 out of 100, Riverside County faces significantly elevated natural disaster threats compared to the typical U.S. county. This "Very High" rating places it well above California's state average of 88.72, indicating exposure to multiple concurrent hazards.

Second-most dangerous county in California

Riverside ranks near the top of California's 58 counties for overall natural disaster risk, exceeded only by a handful of peers. The county's scores reflect extreme exposure to earthquakes (99.81), wildfires (99.97), and floods (99.90)—each individually at dangerous levels.

Riskier than San Bernardino and inland neighbors

Riverside's 99.90 score slightly exceeds San Bernardino County (99.84) and substantially outpaces San Benito (85.24) and San Luis Obispo (95.90) counties. The Inland Empire's twin counties both face extreme multi-hazard risk, making the region California's most disaster-prone.

Wildfires, earthquakes, and floods dominate

Wildfire risk scores 99.97—the highest in the state—with recent fire seasons destroying thousands of structures annually. Earthquake (99.81) and flood (99.90) risks are equally severe, meaning most Riverside properties face credible threats from all three hazards simultaneously.

Comprehensive coverage is essential here

Standard homeowners insurance excludes both earthquakes and wildfires, leaving most Riverside residents significantly underinsured. Consider adding earthquake and wildfire riders to your policy immediately—and verify flood coverage if you're in a mapped flood zone or near rivers.

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

Preparedness Guide

What to Prepare for in Riverside County

Top Hazards by Exposure

  1. #1
    WildfirePrepare
    100th percentile
  2. #2
    FloodPrepare
    100th percentile
  3. #3
    EarthquakePrepare
    100th percentile

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

Risk Advisory: Riverside County

Risk Verdict

Riverside County's composite risk score at the 100th percentile nationally reflects extreme multi-hazard exposure that demands active preparedness. Residents should prioritize a formal household emergency plan, including evacuation routes, insurance review, and a well-stocked emergency kit.

Hazard Breakdown

Wildfire risk is Riverside County's dominant natural hazard, ranked at the 100th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 100th percentile nationally. Additional tracked hazards include earthquake (100th percentile), tornado (87th percentile), hurricane (12th percentile).

Preparedness Context

With wildfire ranked at the 100th percentile nationally, Riverside County is in a zone where air quality can deteriorate rapidly before structures are threatened. An N95 respirator and a HEPA air purifier are practical items for Riverside County households to have on hand before fire season. A secondary flood exposure at the 100th percentile nationally means Riverside County residents face hazards from two distinct natural peril categories during different seasons. Defensible space, insurance review, and an evacuation plan are the three preparedness pillars for Riverside County households — and the insurance review is the one most often deferred by Riverside County residents and most costly to skip when a fire event actually occurs.

Regional Context

Riverside County is 11.2 composite risk points above the California average, indicating that residents face greater natural hazard exposure than most of their in-state neighbors.

Is your household prepared for Riverside 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 Riverside County, CA?
Riverside County has a FEMA National Risk Index rating of Very High, placing it in the 100th 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 Riverside County?
Riverside County is evaluated for five major natural hazard types: wildfire (100th percentile), flooding (100th percentile), earthquake (100th percentile), tornado (87th percentile), hurricane (12th percentile). The highest-risk hazard is wildfire at the 100th 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 Riverside County risk compare to the California average?
Riverside County's composite risk percentile is 100th, compared to the California state average of 89th percentile. The state's overall risk rating is Relatively Moderate. This means Riverside County faces higher natural disaster risk than the typical county in California.
Is Riverside County at risk for wildfire?
Yes, Riverside County's wildfire risk is at the 100th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Riverside County is at the 100th 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 Riverside County higher risk than average?
Riverside County's composite risk score of 100th percentile is above the California state average of 89th percentile. This elevated risk is driven by wildfire exposure (100th percentile), along with flooding and earthquake and 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.