Photo: John Phelan · CC BY-SA 3.0More hazard damage per building is expected in Allenstown than in 76% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Allenstown gets a C− for hazard risk: higher expected damage per building than 76% of U.S. towns, #99 of 126 in New Hampshire. Most of that expected damage is river and rain flooding (80%), then hurricanes (12%). Flood insurance has paid 79 claims here since 1979.
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 Allenstown’s natural hazards
From FEMA’s model and FEMA’s records, below.
What Allenstown 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 Allenstown’s grade
River and rain flooding is 80% of the building damage FEMA expects in Allenstown, and Allenstown’s rate of river and rain flooding damage is higher than 83% of U.S. census tracts. Ice storms add 2%, at a rate in the top 6% of U.S. census tracts.
C− #99 of 126 in New Hampshire; higher expected damage per building than 76% of U.S. towns (21,298).
All of Allenstown’s residents live in one census tract; the figures are that tract’s.
The typical New Hampshire town has higher expected damage than 58% of U.S. towns; within the state, Allenstown has more expected damage per building than 78% of New Hampshire towns.
In dollars, FEMA expects about $1.7M a year in losses across Allenstown: $1.5M to buildings, the rest to people and crops.
Does Allenstown flood? Sometimes: 79 flood claims since 1979
Every paid claim on a federal flood insurance policy in Allenstown, from FEMA’s records: 38.7 per 1,000 homes, more than 91% of the 13,809 U.S. towns with a flood insurance record.
- The March 2010 nor’easter3 claims · $34K
Allenstown isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Merrimack County.12 federal disasters brought FEMA money to Allenstown
Disasters that paid out in Allenstown itself (aid to households or repair grants to the Town of Allenstown), newest first, with that year’s flood claims.
- 2013Severe Winter Storm and Snowstorm$13K to the Town of Allenstown for repairs
- 2012Hurricane Sandy$3K to the Town of Allenstown for repairs
- 2011Tropical Storm Irene$4K to the Town of Allenstown for repairs
- 2010Severe Winter Storm$60K to the Town of Allenstown for repairs3 flood claims paid that year
- 2008Severe Winter Storm$24K to the Town of Allenstown for repairs
- 2008Severe Storms and Flooding$5K to the Town of Allenstown for repairs
Show all 12
- 2007Severe Storms and Flooding57 households applied for aid$324K aid approved$48K to the Town of Allenstown for repairs28 flood claims paid that year
- 2006Severe Storms and Flooding68 households applied for aid$125K aid approved$34K to the Town of Allenstown for repairs25 flood claims paid that year
- 2005Severe Storms and Flooding2 households applied for aid$1K aid approved$2K to the Town of Allenstown for repairs2 flood claims paid that year
- 2003Snow$5K to the Town of Allenstown for repairs
- 2003Snow$5K to the Town of Allenstown for repairs
- 2001Snow$6K to the Town of Allenstown for repairs
Merrimack County has had 24 natural disasters declared by the President since 1953, most often severe storms, then winter storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Allenstown after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Allenstown archive →Allenstown and its neighbors
Allenstown is 4th of the 5 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 |
|---|---|---|---|
| Hooksett | Bless damage than 63% | river and rain flooding | 21 |
| Deerfield | C+more damage than 57% | river and rain flooding | 14 |
| Pembroke | Cmore damage than 68% | river and rain flooding | 31 |
| Allenstown | C−more damage than 76% | river and rain flooding | 79 |
| Epsom | C−more damage than 82% | river and rain flooding | 18 |
| Suncook | — | a Census area inside a town; graded with the town | |
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 Allenstown 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 Allenstown
Is Allenstown at risk for natural disasters?
On FEMA’s National Risk Index, Allenstown has higher expected damage per building than 76% of U.S. towns: C− for hazard risk, #99 of 126 in New Hampshire. Most of the expected damage is river and rain flooding (80%) and hurricanes (12%). 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.
Does Allenstown flood?
Flood insurance has paid 79 claims in Allenstown since 1979, $2.3M in all, or 38.7 per 1,000 homes, more than 91% of U.S. towns with a flood insurance record. 18 properties have flooded more than once. The most claims came from March 2010 Nor'easter (3).
Is Allenstown 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 Merrimack County, 20% of homes in mapped flood zones carry federal flood insurance, and 0.8% of all homes do.
How much is flood insurance in Allenstown?
FEMA’s Community Rating System list shows no discount for Allenstown’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 Allenstown?
By FEMA money that reached Allenstown, Severe Storms and Flooding (2007): 57 households applied for aid, $324K approved, and $48K to the Town of Allenstown for repairs. By flood claims, March 2010 Nor'easter: 3 paid, $34K.
Is Allenstown at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (80%), and Allenstown’s rate for it is higher than 83% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Allenstown.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Allenstown’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.