Photo: John Bortniak · Public domainOn FEMA’s figures, few U.S. towns expect less hazard damage per building than Petersburg, mostly from river and rain flooding
On FEMA’s National Risk Index, Petersburg gets an A+ for hazard risk: among the lowest expected damage per building of U.S. towns, #3 of 41 in Alaska. Most of that expected damage is river and rain flooding (67%), then landslides (23%). FEMA’s files show no paid flood insurance claims here.
Graded on FEMA’s expected yearly building damage per dollar of building value (NRI v1.20, December 2025), weighted by where residents live; flood claims are shown, not graded. How hazard risk is graded
What stands out about Petersburg’s natural hazards
From FEMA’s model and FEMA’s records, below.
What Petersburg faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
River and rain flooding
Landslides
Earthquakes
Shares are of FEMA’s expected building damage, the measure the grade uses; ranks compare each hazard’s building-damage rate with all 85,154 U.S. census tracts. In FEMA’s terms, river and rain flooding is FEMA’s “Inland Flooding” (rivers and streams overflowing their banks, or rain overwhelming drainage). FEMA defines coastal flooding as high or rising tides and storm surge, so surge damage is counted there. Drought isn’t listed: FEMA counts its losses in crops only.
What’s behind Petersburg’s grade
River and rain flooding is 67% of the building damage FEMA expects in Petersburg, and Petersburg’s rate of river and rain flooding damage is lower than 99% of U.S. census tracts. Landslides add 23%, at a rate in the top 1% of U.S. census tracts.
A+ #3 of 41 in Alaska; among the lowest expected damage per building of U.S. towns (21,298).
All of Petersburg’s residents live in one census tract; the figures are that tract’s.
The typical Alaska town has higher expected damage than 93% of U.S. towns; within the state, Petersburg has less expected damage per building than 95% of Alaska towns.
In dollars, FEMA expects about $4.6M a year in losses across Petersburg: $250K to buildings, the rest to people and crops.
Does Petersburg flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Petersburg. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Petersburg isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Petersburg Borough.The storms Petersburg remembers
None of the 1 disasters declared for Petersburg Borough shows FEMA aid or repair money reaching Petersburg itself in FEMA’s records, so these are its biggest flood-claim years.
Petersburg Borough has had 1 natural disasters declared by the President since 1953, most often severe storms.
Petersburg and its neighbors
Petersburg has the lowest expected damage per building of the 1 graded towns here. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Petersburg | A+among the lowest damage | river and rain flooding | 0 |
| Kupreanof | — | 10 residents; we grade 1,000+ | |
Hazard risk = FEMA’s expected yearly building damage per dollar of building value, vs. the 21,298 U.S. towns we grade; the map is shaded by fifths of the same scale. Flood claims = paid federal flood insurance claims on record.
Get ready for what Petersburg faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- Turn around at flooded roads: a foot of moving water can carry off a car.
- Flood insurance usually takes 30 days to start, so buy it before the forecast.
- Keep papers and medicines up high, in a grab-and-go bag.
- Watch for new cracks, tilting trees or suddenly muddy streams after heavy rain.
- Stay off steep slopes in a downpour.
- Leave if you hear rumbling upslope.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- Look up the address on FEMA’s flood map.
- Ask the seller or landlord whether it has ever flooded, and what flood insurance costs there.
- Get a flood insurance quote early: policies usually start 30 days after you buy.
Know where neighbors sign up for alerts? Add it to the Handbook so everyone has it.
Questions about natural hazards in Petersburg
Is Petersburg at risk for natural disasters?
On FEMA’s National Risk Index, Petersburg has among the lowest expected damage per building of U.S. towns: A+ for hazard risk, #3 of 41 in Alaska. Most of the expected damage is river and rain flooding (67%) and landslides (23%). The figures are for the one census tract the town shares with its neighbors. This is FEMA’s model of an average year for today’s buildings, not a forecast.
Is Petersburg in a flood zone?
Flood zones are drawn street by street, so the answer depends on the address: look it up on FEMA’s flood map. In Petersburg Borough, 2.0% of all homes carry federal flood insurance.
How much is flood insurance in Petersburg?
FEMA’s Community Rating System list shows no discount for Petersburg’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
Is Petersburg at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (67%), and Petersburg’s rate for it is lower than 99% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Petersburg.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Petersburg’s residents lived in the 2020 census; OpenFEMA: NFIP redacted claims, multiple-loss properties, community status book and residential penetration rates, housing assistance (owners and renters), public assistance funded projects, hazard mitigation properties and disaster declarations. Homes: Census ACS 2020–24. Preparedness tips: Ready.gov. FEMA’s model is an average of expected damage, not a forecast. How hazard risk is graded.