Photo: Jared Winkler · CC BY-SA 4.0On FEMA’s figures, Sergeant Bluff faces less hazard damage per building than 69% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Sergeant Bluff gets a B+ for hazard risk: lower expected damage per building than 69% of U.S. towns, #44 of 140 in Iowa. Most of that expected damage is river and rain flooding (57%), then tornadoes (27%). 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 Sergeant Bluff 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
Tornadoes
Hail
Strong wind
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 Sergeant Bluff’s grade
River and rain flooding is 57% of the building damage FEMA expects in Sergeant Bluff, and Sergeant Bluff’s rate of river and rain flooding damage is lower than 74% of U.S. census tracts. Tornadoes add 27%, at a rate in the top 2% of U.S. census tracts.
B+ #44 of 140 in Iowa; lower expected damage per building than 69% of U.S. towns (21,298).
Sergeant Bluff’s residents live in 2 census tracts; FEMA’s figures are combined by where they live.
The typical Iowa town has lower expected damage than 57% of U.S. towns; within the state, Sergeant Bluff has less expected damage per building than 69% of Iowa towns.
In dollars, FEMA expects about $2.0M a year in losses across Sergeant Bluff: $1.1M to buildings, the rest to people and crops.
Does Sergeant Bluff flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Sergeant Bluff. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Sergeant Bluff isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Woodbury County.4 federal disasters brought FEMA money to Sergeant Bluff
Disasters that paid out in Sergeant Bluff itself (aid to households or repair grants to the City of Sergeant Bluff), newest first, with that year’s flood claims.
- 2019Severe Storms and Flooding12 households applied for aid$23K aid approved$93K to the City of Sergeant Bluff for repairs
- 2011Flooding$78K to the City of Sergeant Bluff for repairs
- 2009Severe Winter Storms and Snowstorm$19K to the City of Sergeant Bluff for repairs
- 2007Snow$9K to the City of Sergeant Bluff for repairs
Woodbury County has had 15 natural disasters declared by the President since 1953, most often floods, then severe storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Sergeant Bluff after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Sergeant Bluff archive →Sergeant Bluff and its neighbors
Sergeant Bluff has the lowest expected damage per building of the 2 graded towns here. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Sergeant Bluff | B+less damage than 69% | river and rain flooding | 0 |
| Sioux City | C+more damage than 58% | river and rain flooding | 152 |
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 Sergeant Bluff 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.
- Pick your spot now: the lowest floor, an inside room, no windows.
- A watch means be ready; a warning means take cover now.
- Keep shoes and a flashlight by the bed.
- Park in a garage or under cover when storms are forecast.
- Stay away from windows while it falls.
- Photograph roof and car damage for your insurer.
- Trim dead limbs over the house and driveway.
- Tie down trash cans and outdoor furniture.
- Stay clear of downed lines and call the utility.
- 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 Sergeant Bluff
Is Sergeant Bluff at risk for natural disasters?
On FEMA’s National Risk Index, Sergeant Bluff has lower expected damage per building than 69% of U.S. towns: B+ for hazard risk, #44 of 140 in Iowa. Most of the expected damage is river and rain flooding (57%) and tornadoes (27%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Is Sergeant Bluff 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 Woodbury County, 16% of homes in mapped flood zones carry federal flood insurance, and 0.5% of all homes do.
How much is flood insurance in Sergeant Bluff?
FEMA’s Community Rating System list shows no discount for Sergeant Bluff’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 Sergeant Bluff?
By FEMA money that reached Sergeant Bluff, Severe Storms and Flooding (2019): 12 households applied for aid, $23K approved, and $93K to the City of Sergeant Bluff for repairs.
Is Sergeant Bluff at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (57%), and Sergeant Bluff’s rate for it is lower than 74% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Sergeant Bluff.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Sergeant Bluff’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.