Photo: Ebyabe · CC BY-SA 2.5FEMA expects more hazard damage per building in Boston than in 63% of U.S. towns, led by river and rain flooding
On FEMA’s National Risk Index, Boston gets a C+ for hazard risk: higher expected damage per building than 63% of U.S. towns. Most of that expected damage is river and rain flooding (47%), then hurricanes (46%). 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 Boston 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
Hurricanes
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 Boston’s grade
River and rain flooding is 47% of the building damage FEMA expects in Boston, and Boston’s rate of river and rain flooding damage is lower than 61% of U.S. census tracts. Hurricanes add 46%, at a rate in the top 10% of U.S. census tracts.
C+ higher expected damage per building than 63% of U.S. towns (21,298).
All of Boston’s residents live in one census tract; the figures are that tract’s.
In dollars, FEMA expects about $554K a year in losses across Boston: $346K to buildings, the rest to people and crops.
Does Boston flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Boston. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Boston isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Thomas County.6 federal disasters brought FEMA money to Boston
Disasters that paid out in Boston itself (aid to households or repair grants to the City of Boston), newest first, with that year’s flood claims.
- 2024Hurricane Helene240 households applied for aid$324K aid approved$19K to the City of Boston for repairs
- 2024Tropical Storm Debby$5K to the City of Boston for repairs
- 2023Hurricane Idalia6 households applied for aid$733 aid approved$21K to the City of Boston for repairs
- 2018Hurricane Michael38 households applied for aid$20K aid approved
- 2009Severe Storms, Flooding, Tornadoes, and Straight-line Winds1 households applied for aid$308 aid approved
- 2004Tropical Storm Frances$2K to the City of Boston for repairs
Thomas County has had 13 natural disasters declared by the President since 1953, most often hurricanes and tropical storms, then severe storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Boston after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Boston archive →Get ready for what Boston 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.
- The season runs June through November and peaks from mid-August to mid-October.
- Bring in porch furniture and anything the wind can throw.
- Fill the gas tank and charge phones before the storm arrives.
- 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 Boston
Is Boston at risk for natural disasters?
On FEMA’s National Risk Index, Boston has higher expected damage per building than 63% of U.S. towns: C+ for hazard risk. Most of the expected damage is river and rain flooding (47%) and hurricanes (46%). 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 Boston 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 Thomas County, 15% of homes in mapped flood zones carry federal flood insurance, and 0.6% of all homes do.
How much is flood insurance in Boston?
FEMA’s Community Rating System list shows no discount for Boston’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
What was the biggest storm in Boston?
By FEMA money that reached Boston, Hurricane Helene (2024): 240 households applied for aid, $324K approved, and $19K to the City of Boston for repairs.
Is Boston at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (47%), and Boston’s rate for it is lower than 61% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Boston.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Boston’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.