La Paz County, Arizona Natural Disaster Risk
FEMA National Risk Index assessment · AZ
MediumComposite Risk Score
National percentile: 84th
La Paz County faces medium composite natural disaster risk (NRI Risk Index score 83.5, 84th national percentile), driven primarily by riverine flood and heat wave exposure. Expected annual loss across all 18 hazard types is $28M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates La Paz County at medium composite risk, with a National Risk Index score of 83.5 out of 100 — placing it in the 84th national percentile and near the national midpoint for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
The county's risk is driven primarily by riverine flood (rivers and streams overflowing their banks after heavy rain or snowmelt) at Medium risk — $24M in expected annual loss and about 2.93 events per year; heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at Medium risk — $2M in expected annual loss and about 16.02 events per year; and drought (extended dry periods that stress water supplies and agriculture) at Medium risk — $512K in expected annual loss and about 66.04 events per year. Across all hazards, FEMA estimates $28M in expected annual loss for a population of 16K.
Beyond physical exposure, La Paz County has a very high social vulnerability rating (how susceptible the population is to harm) and a very low community resilience rating (its capacity to prepare for and recover from disasters). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
History supports the rating: La Paz County has received 7 federal disaster declarations since 1983, including 2 for biological events and 2 for flood events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 15 Arizona counties, La Paz County ranks #12 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Riverine Flood | Medium | 2.93 / yr | $24M |
| Heat Wave | Medium | 16.02 / yr | $2M |
| Drought | Medium | 66.04 / yr | $512K |
| Earthquake | Low | 0.04 / yr | $801K |
| Wildfire | Low | 0.00 / yr | $94K |
| Landslide | Very Low | 2.55 / yr | $1K |
| Volcanic Activity | Very Low | 0.00 / yr | $4 |
| Strong Wind | Low | 0.36 / yr | $93K |
| Hurricane | Very Low | 0.02 / yr | $2K |
| Avalanche | Very Low | 0.01 / yr | $9 |
| Hail | Very Low | 0.06 / yr | $12K |
| Lightning | Very Low | 24.53 / yr | $11K |
| Tornado | Very Low | 0.07 / yr | $8K |
| Winter Weather | Very Low | 0.04 / yr | $44 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
La Paz County has received 7 federal disaster declarations since 1983, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Biological (2), Flood (2), Severe Storm (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| November 2014 | Flood | Severe Storms and Flooding |
| March 2010 | Severe Storm | Severe Winter Storms and Flooding |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| October 2000 | Severe Storm | Severe Storms and Flooding |
| July 1983 | Flood | Flooding |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for La Paz County?
La Paz County has a composite FEMA National Risk Index score of 83.5 out of 100, placing it in the Medium category and the 84th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in La Paz County?
The three highest-rated hazards are Riverine Flood (Medium, $24M EAL), Heat Wave (Medium, $2M EAL), Drought (Medium, $512K EAL). These account for most of the county's expected annual losses.
How does La Paz County compare to other Arizona counties?
La Paz County ranks #12 of 15 Arizona counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has La Paz County had?
FEMA records 7 federal disaster declarations for La Paz County since 1983, most often 2 for biological events and 2 for flood events. The most recent was Covid-19 Pandemic, declared in April 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. La Paz County's $28M EAL is a statistical average, not a guarantee for any specific year or address.