Photo: Beyond My Ken3 · CC BY-SA 4.0Less hazard damage per building is expected in Chilmark than in 73% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Chilmark gets a B+ for hazard risk: lower expected damage per building than 73% of U.S. towns. Most of that expected damage is river and rain flooding (63%), then hurricanes (33%). 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 Chilmark 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 Chilmark’s grade
River and rain flooding is 63% of the building damage FEMA expects in Chilmark, and Chilmark’s rate of river and rain flooding damage is lower than 71% of U.S. census tracts. Coastal flooding adds 2%, at a rate in the top 6% of U.S. census tracts.
B+ lower expected damage per building than 73% of U.S. towns (21,298).
All of Chilmark’s residents live in one census tract; the figures are that tract’s.
In dollars, FEMA expects about $418K a year in losses across Chilmark: $399K to buildings, the rest to people and crops.
Does Chilmark flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Chilmark. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Chilmark isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Dukes County.6 federal disasters brought FEMA money to Chilmark
Disasters that paid out in Chilmark itself (aid to households or repair grants to the Town of Chilmark), newest first, with that year’s flood claims.
- 2015Severe Winter Storm, Snowstorm, and Flooding$20K to the Town of Chilmark for repairs
- 2012Hurricane Sandy$4K to the Town of Chilmark for repairs
- 2011Tropical Storm Irene$18K to the Town of Chilmark for repairs
- 2007Severe Storms and Inland and Coastal Flooding$9K to the Town of Chilmark for repairs
- 2005Record And/or Near Record Snow$10K to the Town of Chilmark for repairs
- 2003Snow$6K to the Town of Chilmark for repairs
Dukes County has had 16 natural disasters declared by the President since 1953, most often hurricanes and tropical storms, then winter storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Chilmark after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Chilmark archive →Chilmark and its neighbors
Chilmark is 2nd of the 2 graded towns here, from least expected damage per building to most. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| West Tisbury | B+less damage than 73% | river and rain flooding | 4 |
| Chilmark | B+less damage than 73% | river and rain flooding | 0 |
| Aquinnah | — | 666 residents; we grade 1,000+ | |
| Gosnold | — | 31 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 Chilmark 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 Chilmark
Is Chilmark at risk for natural disasters?
On FEMA’s National Risk Index, Chilmark has lower expected damage per building than 73% of U.S. towns: B+ for hazard risk. Most of the expected damage is river and rain flooding (63%) and hurricanes (33%). 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 Chilmark 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 Dukes County, 53% of homes in mapped flood zones carry federal flood insurance, and 5.3% of all homes do.
How much is flood insurance in Chilmark?
FEMA’s Community Rating System list shows no discount for Chilmark’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 Chilmark?
By FEMA money that reached Chilmark, Severe Winter Storm, Snowstorm, and Flooding (2015): $20K to the Town of Chilmark for repairs.
Is Chilmark at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (63%), and Chilmark’s rate for it is lower than 71% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Chilmark.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Chilmark’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.