Photo: TCP04 · CC BY 4.0On FEMA’s figures, Potosi faces more hazard damage per building than 80% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Potosi gets a C− for hazard risk: higher expected damage per building than 80% of U.S. towns, #199 of 247 in Missouri. Most of that expected damage is river and rain flooding (58%), then earthquakes (24%). Flood insurance has paid 9 claims here since 1985.
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 Potosi 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
Earthquakes
Tornadoes
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 Potosi’s grade
River and rain flooding is 58% of the building damage FEMA expects in Potosi, and Potosi’s rate of river and rain flooding damage is higher than 72% of U.S. census tracts. Strong wind adds 6%, at a rate in the top 3% of U.S. census tracts.
C− #199 of 247 in Missouri; higher expected damage per building than 80% of U.S. towns (21,298).
Potosi’s residents live in 3 census tracts; FEMA’s figures are combined by where they live.
The typical Missouri town has higher expected damage than 59% of U.S. towns; within the state, Potosi has more expected damage per building than 80% of Missouri towns.
In dollars, FEMA expects about $2.4M a year in losses across Potosi: $878K to buildings, the rest to people and crops.
Does Potosi flood? Rarely: 9 flood claims since 1985
Every paid claim on a federal flood insurance policy in Potosi, from FEMA’s records: 7.2 per 1,000 homes, more than 68% of the 13,809 U.S. towns with a flood insurance record.
Potosi isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Washington County.8 federal disasters brought FEMA money to Potosi
Disasters that paid out in Potosi itself (aid to households or repair grants to the City of Potosi), newest first, with that year’s flood claims.
- 2025Severe Storms, Straight-line Winds, Tornadoes, and Flooding$53K to the City of Potosi for repairs
- 2025Severe Storms, Straight-line Winds, Tornadoes, and Flooding11 households applied for aid$117K aid approved
- 2011Severe Storms, Tornadoes, and Flooding$6K to the City of Potosi for repairs
- 2009Severe Storms, Tornadoes, and Flooding7 households applied for aid$14K aid approved1 flood claim paid that year
- 2008Severe Storms and Flooding26 households applied for aid$28K aid approved
- 2006Severe Winter Storms$27K to the City of Potosi for repairs
Show all 8
- 2006Severe Storms$40K to the City of Potosi for repairs
- 2003Severe Storms, Tornadoes, and Flooding11 households applied for aid$13K aid approved
Washington County has had 24 natural disasters declared by the President since 1953, most often severe storms, then floods. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of Potosi after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Potosi archive →Get ready for what Potosi 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.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- 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.
- 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 Potosi
Is Potosi at risk for natural disasters?
On FEMA’s National Risk Index, Potosi has higher expected damage per building than 80% of U.S. towns: C− for hazard risk, #199 of 247 in Missouri. Most of the expected damage is river and rain flooding (58%) and earthquakes (24%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Potosi flood?
Flood insurance has paid 9 claims in Potosi since 1985, $87K in all, or 7.2 per 1,000 homes, more than 68% of U.S. towns with a flood insurance record. 1 properties have flooded more than once.
Is Potosi 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 Washington County, 4% of homes in mapped flood zones carry federal flood insurance, and 0.1% of all homes do.
How much is flood insurance in Potosi?
FEMA’s Community Rating System list shows no discount for Potosi’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 Potosi?
By FEMA money that reached Potosi, Severe Storms, Straight-line Winds, Tornadoes, and Flooding (2025): 11 households applied for aid, $117K approved.
Is Potosi at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (58%), and Potosi’s rate for it is higher than 72% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Potosi.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Potosi’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.