Photo: WalkingGeek from Westport, CT, USA · CC BY 2.0For coastal flooding, Mamaroneck’s building-damage rate is in the top 2% of U.S. census tracts
On FEMA’s National Risk Index, Mamaroneck gets a B for hazard risk: lower expected damage per building than 56% of U.S. towns, #484 of 758 in New York. Most of that expected damage is river and rain flooding (78%). Flood insurance has paid 524 claims here since 1978.
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 Mamaroneck’s natural hazards
From FEMA’s model and FEMA’s records, below.
What Mamaroneck 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
Coastal 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 Mamaroneck’s grade
River and rain flooding is 78% of the building damage FEMA expects in Mamaroneck, and Mamaroneck’s rate of river and rain flooding damage is higher than 60% of U.S. census tracts. Coastal flooding adds 10%, at a rate in the top 2% of U.S. census tracts.
B #484 of 758 in New York; lower expected damage per building than 56% of U.S. towns (21,298).
Mamaroneck’s residents live in 5 census tracts; FEMA’s figures are combined by where they live.
The typical New York town has lower expected damage than 69% of U.S. towns; within the state, Mamaroneck has more expected damage per building than 64% of New York towns.
In dollars, FEMA expects about $11.3M a year in losses across Mamaroneck: $8.0M to buildings, the rest to people and crops.
Does Mamaroneck flood? Yes: 524 flood claims since 1978
Every paid claim on a federal flood insurance policy in Mamaroneck, from FEMA’s records: 42.2 per 1,000 homes, more than 91% of the 13,809 U.S. towns with a flood insurance record.
- Hurricane Ida104 claims · $5.0M
- The April 2007 nor’easter58 claims · $1.7M
Mamaroneck isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Westchester County.9 federal disasters brought FEMA money to Mamaroneck
Disasters that paid out in Mamaroneck itself (aid to households or repair grants to the Town of Mamaroneck), newest first, with that year’s flood claims.
- 2021Remnants of Hurricane Ida$1.7M to the Town of Mamaroneck for repairs104 flood claims paid for it, $5.0M
- 2020Tropical Storm Isaias$319K to the Town of Mamaroneck for repairs
- 2012Hurricane Sandy$465K to the Town of Mamaroneck for repairs16 flood claims paid for it, $781K
- 2011Hurricane Irene$83K to the Town of Mamaroneck for repairs14 flood claims paid for it, $336K
- 2011Hurricane Irene$66K to the Town of Mamaroneck for repairs14 flood claims paid for it, $336K
- 2010Severe Storms and Flooding$89K to the Town of Mamaroneck for repairs9 flood claims paid that year
Show all 9
- 2007Severe Storms and Inland and Coastal Flooding$151K to the Town of Mamaroneck for repairs66 flood claims paid that year
- 2003Snow$35K to the Town of Mamaroneck for repairs
- 1999Hurricane Floyd Major Disaster Declarations$25K to the Town of Mamaroneck for repairs3 flood claims paid that year
Westchester County has had 23 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; the 2001 World Trade Center declarations.
Old photos of Mamaroneck after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Mamaroneck archive →Mamaroneck and its neighbors
Mamaroneck is 5th of the 8 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 |
|---|---|---|---|
| Scarsdale | Aless damage than 90% | river and rain flooding | 403 |
| New Rochelle | Aless damage than 89% | river and rain flooding | 752 |
| Harrison | Aless damage than 89% | river and rain flooding | 777 |
| Larchmont | A−less damage than 76% | river and rain flooding | 381 |
| Mamaroneck | Bless damage than 56% | river and rain flooding | 524 |
| Rye | C+more damage than 57% | river and rain flooding | 1,566 |
| Mamaroneck | C+more damage than 60% | river and rain flooding | 1,767 |
| Rye | C+more damage than 62% | river and rain flooding | 786 |
| Harrison | — | not graded yet | |
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 Mamaroneck 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.
- Know your evacuation zone and the way off the coast.
- Storm surge comes fast: leave when you’re told, not when the water arrives.
- Move cars to high ground before king tides and nor’easters.
- 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 Mamaroneck
Is Mamaroneck at risk for natural disasters?
On FEMA’s National Risk Index, Mamaroneck has lower expected damage per building than 56% of U.S. towns: B for hazard risk, #484 of 758 in New York. Most of the expected damage is river and rain flooding (78%) and coastal flooding (10%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Mamaroneck flood?
Flood insurance has paid 524 claims in Mamaroneck since 1978, $10.5M in all, or 42.2 per 1,000 homes, more than 91% of U.S. towns with a flood insurance record. 65 properties have flooded more than once. The most claims came from Hurricane Ida (104).
Is Mamaroneck 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 Westchester County, 64% of homes in mapped flood zones carry federal flood insurance, and 3.0% of all homes do.
How much is flood insurance in Mamaroneck?
FEMA’s Community Rating System list shows no discount for Mamaroneck’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 Mamaroneck?
By FEMA money that reached Mamaroneck, Remnants of Hurricane Ida (2021): $1.7M to the Town of Mamaroneck for repairs. By flood claims, Hurricane Ida: 104 paid, $5.0M.
Is Mamaroneck at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (78%), and Mamaroneck’s rate for it is higher than 60% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Mamaroneck.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Mamaroneck’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.