Petersburg Borough, AK
FEMA National Risk Index scores, disaster declarations & hazard data
Petersburg Borough has experienced 3 federally declared disasters since 2020, most recently Severe Storm, Flooding, Landslides, And Mudslides in 2021. Its overall natural hazard risk is rated Very Low — among the lowest-risk counties in the country.
Petersburg Borough's highest-rated hazards are landslide, avalanche, and volcanic activity, with its top risk rated "Relatively High" by FEMA's National Risk Index.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Petersburg Borough has been designated in 3 declarations since 2020, covering 2 disaster types including biological (2), mud/landslide (1).
| Year | Type | Event name |
|---|---|---|
| 2021 | Mud/Landslide | Severe Storm, Flooding, Landslides, And Mudslides |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Very Low | 3.4 | 0 | 0 | — |
| Inland Flooding | Very Low | 1 | 0 | 0 | — |
| Coastal Flooding | No Rating | 0 | 0 | 0 | — |
| Earthquake | Very Low | 18.3 | 8 | — | — |
| Heat Wave | Insufficient Data | — | 0 | 0 | — |
| Tornado | Very Low | 0.3 | 0 | 0 | — |
| Hurricane | Not Applicable | — | 0 | 0 | — |
| Hail | No Rating | 0 | 0 | 0 | — |
| Strong Wind | No Rating | 0 | 0 | 0 | — |
| Winter Weather | Relatively Low | 30.9 | 0 | 0 | — |
| Ice Storm | Very Low | 14.4 | — | — | — |
| Cold Wave | Very Low | 4 | — | — | — |
| Lightning | Very Low | 0.4 | 0 | 0 | — |
| Drought | No Rating | 0 | 0 | 0 | — |
| Landslide | Relatively High | 99.7 | 0 | 0 | — |
| Avalanche | Relatively High | 92.7 | — | — | — |
| Tsunami | Insufficient Data | — | — | — | — |
| Volcanic Activity | Relatively Low | 86.3 | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Petersburg Borough ranks in the 69th percentile (Moderate) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 69th | Moderate |
| Socioeconomic status | 39th | Low |
| Household characteristics | 74th | Moderate |
| Racial & ethnic minority status | 84th | High |
| Housing type & transportation | 81st | High |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 4th | Very Low |
| Risk to homes | 4th | Very Low |
| Buildings in direct exposure zone | 59.0% | — |
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Petersburg Borough?
According to the FEMA National Risk Index, the highest-risk hazards in Petersburg Borough, Alaska are landslide, avalanche, and volcanic activity. The county's overall natural hazard risk is rated Very Low — among the lowest-risk counties in the country.
Has Petersburg Borough received federal disaster declarations?
Yes. Petersburg Borough has received 3 federal disaster declarations since 2020, including declarations in 2021. The most common disaster type on record is biological (2 declarations).
Has Petersburg Borough had any FEMA disaster declarations in 2024, 2025, or 2026?
No federal disaster declarations have been recorded for Petersburg Borough since the start of 2024. Its most recent declaration on record is Severe Storm, Flooding, Landslides, And Mudslides in 2021.
How does Petersburg Borough's natural hazard risk compare to nearby counties?
Among neighboring counties, Sitka City and Borough, AK has the highest overall natural hazard risk (Very Low) and Wrangell City and Borough, AK has the lowest (Very Low). Petersburg Borough is rated Very Low overall.
How is Petersburg Borough's composite disaster risk index calculated?
Petersburg Borough's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Petersburg Borough's composite score of 15 means its overall natural hazard risk is higher than 15% of US counties.