William Gunnell House · Photo: JERRYE & ROY KLOTZ MD · CC BY-SA 3.0Less hazard damage per building is expected in Great Falls than in 82% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Great Falls gets an A− for hazard risk: lower expected damage per building than 82% of U.S. towns, #119 of 253 in Virginia. Most of that expected damage is river and rain flooding (83%). Flood insurance has paid 15 claims here since 2001.
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 Great Falls 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 Great Falls’ grade
River and rain flooding is 83% of the building damage FEMA expects in Great Falls, and Great Falls’ rate of river and rain flooding damage is lower than 60% of U.S. census tracts. Next is hurricanes at 10% (higher than 74% of U.S. census tracts).
A− #119 of 253 in Virginia; lower expected damage per building than 82% of U.S. towns (21,298).
Great Falls’ residents live in 5 census tracts; FEMA’s figures are combined by where they live.
The typical Virginia town has lower expected damage than 81% of U.S. towns; within the state, Great Falls has less expected damage per building than 53% of Virginia towns.
In dollars, FEMA expects about $5.2M a year in losses across Great Falls: $4.8M to buildings, the rest to people and crops.
Does Great Falls flood? Sometimes: 15 flood claims since 2001
Every paid claim on a federal flood insurance policy in Great Falls, from FEMA’s records: 2.9 per 1,000 homes, fewer than 52% of the 13,809 U.S. towns with a flood insurance record.
Great Falls isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Fairfax County.1 federal disaster brought FEMA money to Great Falls
Disasters that paid out in Great Falls itself (aid to households or repair grants to Great Falls), newest first, with that year’s flood claims.
- 2003Hurricane Isabel7 households applied for aid$358 aid approved1 flood claim paid that year
Fairfax County has had 16 natural disasters declared by the President since 1953, most often winter storms, then hurricanes and tropical storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Great Falls after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Great Falls archive →Great Falls and its neighbors
Great Falls is 6th 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 |
|---|---|---|---|
| Darnestown | A+less damage than 96% | river and rain flooding | 4 |
| Potomac | A+less damage than 96% | river and rain flooding | 30 |
| Travilah | Aless damage than 93% | river and rain flooding | 3 |
| Great Falls Crossing | Aless damage than 87% | river and rain flooding | — |
| McLean | Aless damage than 85% | river and rain flooding | 57 |
| Great Falls | A−less damage than 82% | river and rain flooding | 15 |
| Wolf Trap | A−less damage than 81% | river and rain flooding | 6 |
| Dranesville | B+less damage than 73% | river and rain flooding | 2 |
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 Great Falls 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 Great Falls
Is Great Falls at risk for natural disasters?
On FEMA’s National Risk Index, Great Falls has lower expected damage per building than 82% of U.S. towns: A− for hazard risk, #119 of 253 in Virginia. Most of the expected damage is river and rain flooding (83%) and hurricanes (10%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Great Falls flood?
Flood insurance has paid 15 claims in Great Falls since 2001, $191K in all, or 2.9 per 1,000 homes, fewer than 52% of U.S. towns with a flood insurance record.
Is Great Falls 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 Fairfax County, 22% of homes in mapped flood zones carry federal flood insurance, and 1.1% of all homes do.
How much is flood insurance in Great Falls?
FEMA’s Community Rating System list shows no discount for Great Falls’ 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 Great Falls?
By FEMA money that reached Great Falls, Hurricane Isabel (2003): 7 households applied for aid, $358 approved.
Is Great Falls at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (83%), and Great Falls’ rate for it is lower than 60% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Great Falls.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Great Falls’ 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.