Anchorage Municipality, Alaska Natural Disaster Risk
FEMA National Risk Index assessment · AK
HighComposite Risk Score
National percentile: 97th
Anchorage Municipality faces high composite natural disaster risk (NRI Risk Index score 97.4, 97th national percentile), driven primarily by earthquake and landslide exposure. Expected annual loss across all 18 hazard types is $367M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Anchorage Municipality at high composite risk, with a National Risk Index score of 97.4 out of 100 — placing it in the 97th national percentile and in the upper tier of natural-disaster risk nationally. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Anchorage Municipality's expected losses come from earthquake (ground shaking from sudden movement along geologic faults) at High risk — $353M in expected annual loss and about 0.16 events per year; landslide (downhill movement of rock, soil, and debris on unstable slopes) at High risk — $2M in expected annual loss and about 32.43 events per year; and winter weather (heavy snow, blizzards, and hazardous winter conditions) at Very High risk — $2M in expected annual loss and about 9.00 events per year. Across all hazards, FEMA estimates $367M in expected annual loss for a population of 291K.
Beyond physical exposure, Anchorage Municipality has a very low social vulnerability rating (how susceptible the population is to harm) and a low community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The federal record bears this out: Anchorage Municipality has received 7 federal disaster declarations since 1995, including 2 for biological events and 2 for earthquake events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 30 Alaska counties, Anchorage Municipality ranks #1 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Earthquake | High | 0.16 / yr | $353M |
| Landslide | High | 32.43 / yr | $2M |
| Winter Weather | Very High | 9.00 / yr | $2M |
| Avalanche | Very High | 1.00 / yr | $7M |
| Volcanic Activity | Low | 0.01 / yr | $7K |
| Wildfire | Low | 0.00 / yr | $471K |
| Tsunami | Low | 0.30 / yr | $2M |
| Lightning | Low | 9.39 / yr | $201K |
| Coastal Flood | Very Low | 0.01 / yr | $4K |
| Cold Wave | Low | 0.06 / yr | $492K |
| Ice Storm | Very Low | 0.01 / yr | $27K |
| Hail | Very Low | 0.02 / yr | $27K |
| Tornado | Very Low | 0.00 / yr | $1 |
| Riverine Flood | Very Low | 0.04 / yr | $397 |
| Drought | Very Low | 1.39 / yr | $0 |
| Heat Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Strong Wind | Very Low | 0.00 / yr | $0 |
Disaster History
Anchorage Municipality has received 7 federal disaster declarations since 1995, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Biological (2), Earthquake (2), Severe Storm (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| January 2019 | Earthquake | Earthquake |
| November 2018 | Earthquake | Earthquake |
| April 2003 | Severe Storm | Severe Winter Storm, Including High Winds and Freezing Temperatures |
| February 2000 | Severe Storm | Severe Winter Storms and Avalanches |
| October 1995 | Flood | Flooding |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Anchorage Municipality?
Anchorage Municipality has a composite FEMA National Risk Index score of 97.4 out of 100, placing it in the High category and the 97th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Anchorage Municipality?
The three highest-rated hazards are Earthquake (High, $353M EAL), Landslide (High, $2M EAL), Winter Weather (Very High, $2M EAL). These account for most of the county's expected annual losses.
How does Anchorage Municipality compare to other Alaska counties?
Anchorage Municipality ranks #1 of 30 Alaska counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Anchorage Municipality had?
FEMA records 7 federal disaster declarations for Anchorage Municipality since 1995, most often 2 for biological events and 2 for earthquake 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. Anchorage Municipality's $367M EAL is a statistical average, not a guarantee for any specific year or address.