Albert and Mary Shekey House · Photo: Boscophotos · CC BY-SA 3.0On FEMA’s figures, Koshkonong faces about as much hazard damage per building as the typical U.S. town, mostly from river and rain flooding
On FEMA’s National Risk Index, Koshkonong gets a C+ for hazard risk: higher expected damage per building than 60% of U.S. towns, #327 of 362 in Wisconsin. Most of that expected damage is river and rain flooding (81%), then tornadoes (10%). 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 Koshkonong 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
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 Koshkonong’s grade
River and rain flooding is 81% of the building damage FEMA expects in Koshkonong, and Koshkonong’s rate of river and rain flooding damage is higher than 73% of U.S. census tracts. Next is tornadoes at 10% (higher than 83% of U.S. census tracts).
C+ #327 of 362 in Wisconsin; higher expected damage per building than 60% of U.S. towns (21,298).
Koshkonong’s residents live in 7 census tracts; FEMA’s figures are combined by where they live.
The typical Wisconsin town has lower expected damage than 79% of U.S. towns; within the state, Koshkonong has more expected damage per building than 90% of Wisconsin towns.
In dollars, FEMA expects about $2.3M a year in losses across Koshkonong: $1.7M to buildings, the rest to people and crops.
Does Koshkonong flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Koshkonong. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Koshkonong isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Jefferson County.3 federal disasters brought FEMA money to Koshkonong
Disasters that paid out in Koshkonong itself (aid to households or repair grants to the Town of Koshkonong), newest first, with that year’s flood claims.
- 2008Severe Storms, Tornadoes, and Flooding$13K to the Town of Koshkonong for repairs
- 2008Record Snow and Near Record Snow$8K to the Town of Koshkonong for repairs
- 2004Severe Storms and Flooding$66K to the Town of Koshkonong for repairs
Jefferson County has had 11 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 Koshkonong after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Koshkonong archive →Koshkonong and its neighbors
Koshkonong is 4th 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 |
|---|---|---|---|
| Hebron | B+less damage than 70% | river and rain flooding | 14 |
| Jefferson | Bless damage than 58% | river and rain flooding | — |
| Lima | B−less damage than 53% | river and rain flooding | — |
| Koshkonong | C+more damage than 60% | river and rain flooding | 0 |
| Milton | C+more damage than 65% | river and rain flooding | 1 |
| Fort Atkinson | Cmore damage than 68% | river and rain flooding | 49 |
| Sumner | — | 824 residents; we grade 1,000+ | |
| Cold Spring | — | not graded yet | |
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 Koshkonong 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.
- 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 Koshkonong
Is Koshkonong at risk for natural disasters?
On FEMA’s National Risk Index, Koshkonong has higher expected damage per building than 60% of U.S. towns: C+ for hazard risk, #327 of 362 in Wisconsin. Most of the expected damage is river and rain flooding (81%) and tornadoes (10%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Is Koshkonong 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 Jefferson County, 17% of homes in mapped flood zones carry federal flood insurance, and 0.5% of all homes do.
How much is flood insurance in Koshkonong?
FEMA’s Community Rating System list shows no discount for Koshkonong’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 Koshkonong?
By FEMA money that reached Koshkonong, Severe Storms and Flooding (2004): $66K to the Town of Koshkonong for repairs.
Is Koshkonong at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (81%), and Koshkonong’s rate for it is higher than 73% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Koshkonong.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Koshkonong’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.