Sterling Opera House · Photo: Own work · CC BY-SA 3.0More hazard damage per building is expected in Derby than in 75% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Derby gets a C− for hazard risk: higher expected damage per building than 75% of U.S. towns, #125 of 155 in Connecticut. Most of that expected damage is river and rain flooding (79%), then hurricanes (16%). Flood insurance has paid 28 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 Derby 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 Derby’s grade
River and rain flooding is 79% of the building damage FEMA expects in Derby, and Derby’s rate of river and rain flooding damage is higher than 82% of U.S. census tracts. Next is hurricanes at 16% (higher than 85% of U.S. census tracts).
C− #125 of 155 in Connecticut; higher expected damage per building than 75% of U.S. towns (21,298).
Derby’s residents live in 2 census tracts; FEMA’s figures are combined by where they live.
The typical Connecticut town has higher expected damage than 62% of U.S. towns; within the state, Derby has more expected damage per building than 81% of Connecticut towns.
In dollars, FEMA expects about $3.7M a year in losses across Derby: $3.4M to buildings, the rest to people and crops.
Does Derby flood? Sometimes: 28 flood claims since 1978
Every paid claim on a federal flood insurance policy in Derby, from FEMA’s records: 4.5 per 1,000 homes, more than 58% of the 13,809 U.S. towns with a flood insurance record.
- The March 2010 nor’easter1 claim · $3K
- Hurricane Irene1 claim · $6K
Derby isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: the county.4 federal disasters brought FEMA money to Derby
Disasters that paid out in Derby itself (aid to households or repair grants to the City of Derby), newest first, with that year’s flood claims.
- 2012Hurricane Sandy27 households applied for aid$1K aid approved
- 2011Tropical Storm Irene13 households applied for aid$1K aid approved1 flood claim paid for it, $6K
- 2010Severe Storms and Flooding4 households applied for aid$291 aid approved1 flood claim paid that year
- 2007Severe Storms and Flooding7 households applied for aid$6K aid approved2 flood claims paid that year
Old photos of Derby after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Derby archive →Derby and its neighbors
Derby is 6th of the 6 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 |
|---|---|---|---|
| Woodbridge | B−more damage than 51% | river and rain flooding | 60 |
| Seymour | C+more damage than 55% | river and rain flooding | 22 |
| Orange | C+more damage than 56% | river and rain flooding | 129 |
| Shelton | C+more damage than 64% | river and rain flooding | 138 |
| Ansonia | Cmore damage than 70% | river and rain flooding | 1 |
| Derby | C−more damage than 75% | river and rain flooding | 28 |
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 Derby 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 Derby
Is Derby at risk for natural disasters?
On FEMA’s National Risk Index, Derby has higher expected damage per building than 75% of U.S. towns: C− for hazard risk, #125 of 155 in Connecticut. Most of the expected damage is river and rain flooding (79%) and hurricanes (16%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Derby flood?
Flood insurance has paid 28 claims in Derby since 1978, $119K in all, or 4.5 per 1,000 homes, more than 58% of U.S. towns with a flood insurance record. 3 properties have flooded more than once. The most claims came from March 2010 Nor'easter (1).
Is Derby 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 the county, 38% of homes in mapped flood zones carry federal flood insurance, and 0.4% of all homes do.
How much is flood insurance in Derby?
FEMA’s Community Rating System list shows no discount for Derby’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 Derby?
By FEMA money that reached Derby, Severe Storms and Flooding (2007): 7 households applied for aid, $6K approved. By flood claims, March 2010 Nor'easter: 1 paid, $3K.
Is Derby at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (79%), and Derby’s rate for it is higher than 82% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Derby.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Derby’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.