Del Norte County, California Natural Disaster Risk
FEMA National Risk Index assessment · CA
HighComposite Risk Score
National percentile: 94th
Del Norte County faces high composite natural disaster risk (NRI Risk Index score 94.4, 94th national percentile), driven primarily by landslide and tsunami exposure. Expected annual loss across all 18 hazard types is $142M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Del Norte County carries a high composite natural disaster risk, with a National Risk Index score of 94.4 out of 100 — placing it in the 94th 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 Del Norte County's expected losses come from landslide (downhill movement of rock, soil, and debris on unstable slopes) at High risk — $847K in expected annual loss and about 2.18 events per year; tsunami (series of ocean waves triggered by undersea earthquakes or landslides) at Very High risk — $114M in expected annual loss and about 0.23 events per year; and earthquake (ground shaking from sudden movement along geologic faults) at Medium risk — $11M in expected annual loss and about 0.02 events per year. Across all hazards, FEMA estimates $142M in expected annual loss for a population of 28K.
Beyond physical exposure, Del Norte County has a medium 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: Del Norte County has received 21 federal disaster declarations since 1964, including 8 for flood events and 6 for severe storm events. The most recent was Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides (severe storm), declared in April 2023.
Among 58 California counties, Del Norte County ranks #30 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Landslide | High | 2.18 / yr | $847K |
| Tsunami | Very High | 0.23 / yr | $114M |
| Earthquake | Medium | 0.02 / yr | $11M |
| Wildfire | Low | 0.00 / yr | $650K |
| Riverine Flood | Medium | 0.32 / yr | $16M |
| Coastal Flood | Very Low | 3.63 / yr | $25K |
| Avalanche | Very Low | 0.01 / yr | $229 |
| Drought | Low | 19.62 / yr | $58K |
| Heat Wave | Very Low | 1.96 / yr | $31K |
| Lightning | Very Low | 6.99 / yr | $38K |
| Winter Weather | Very Low | 13.27 / yr | $6K |
| Hail | Very Low | 0.05 / yr | $9K |
| Strong Wind | Very Low | 0.03 / yr | $20K |
| Tornado | Very Low | 0.01 / yr | $8K |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Del Norte County has received 21 federal disaster declarations since 1964, most recently Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides in April 2023. Most frequent causes: Flood (8), Severe Storm (6), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2023 | Severe Storm | Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| March 2023 | Flood | Severe Winter Storms, Flooding, Landslides, and Mudslides |
| January 2023 | Flood | Severe Winter Storms, Flooding, Landslides, and Mudslides |
| October 2020 | Fire | Wildfires |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| May 2019 | Severe Storm | Severe Winter Storms, Flooding, Landslides, and Mudslides |
| April 2017 | Flood | Severe Winter Storms, Flooding, and Mudslides |
| April 2011 | Tsunami | Tsunami Waves |
| February 2006 | Severe Storm | Severe Storms, Flooding, Mudslides, and Landslides |
Showing the 10 most recent of 21 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Del Norte County?
Del Norte County has a composite FEMA National Risk Index score of 94.4 out of 100, placing it in the High category and the 94th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Del Norte County?
The three highest-rated hazards are Landslide (High, $847K EAL), Tsunami (Very High, $114M EAL), Earthquake (Medium, $11M EAL). These account for most of the county's expected annual losses.
How does Del Norte County compare to other California counties?
Del Norte County ranks #30 of 58 California counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Del Norte County had?
FEMA records 21 federal disaster declarations for Del Norte County since 1964, most often 8 for flood events and 6 for severe storm events. The most recent was Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides, declared in April 2023.
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. Del Norte County's $142M EAL is a statistical average, not a guarantee for any specific year or address.