Photo: Jauerback · CC BY-SA 4.0FEMA expects less hazard damage per building in Big Rock than in 74% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Big Rock gets a B+ for hazard risk: lower expected damage per building than 74% of U.S. towns. Most of that expected damage is river and rain flooding (81%), then tornadoes (14%). 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 Big Rock 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
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 Big Rock’s grade
River and rain flooding is 81% of the building damage FEMA expects in Big Rock, and Big Rock’s rate of river and rain flooding damage is lower than 53% of U.S. census tracts. Next is tornadoes at 14% (higher than 81% of U.S. census tracts).
B+ lower expected damage per building than 74% of U.S. towns (21,298).
All of Big Rock’s residents live in one census tract; the figures are that tract’s.
In dollars, FEMA expects about $645K a year in losses across Big Rock: $378K to buildings, the rest to people and crops.
Does Big Rock flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Big Rock. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Big Rock isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Kane County.1 federal disaster brought FEMA money to Big Rock
Disasters that paid out in Big Rock itself (aid to households or repair grants to the Village of Big Rock), newest first, with that year’s flood claims.
- 2013Severe Storms, Straight-line Winds, and Flooding3 households applied for aid$8K aid approved
Kane County has had 13 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 Big Rock after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Big Rock archive →Big Rock and its neighbors
Big Rock 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 |
|---|---|---|---|
| Big Rock | B+less damage than 74% | river and rain flooding | 0 |
| Sugar Grove | B+less damage than 69% | 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 Big Rock 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.
- 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 Big Rock
Is Big Rock at risk for natural disasters?
On FEMA’s National Risk Index, Big Rock has lower expected damage per building than 74% of U.S. towns: B+ for hazard risk. Most of the expected damage is river and rain flooding (81%) and tornadoes (14%). The figures are for the one census tract the town shares with its neighbors. This is FEMA’s model of an average year for today’s buildings, not a forecast.
Is Big Rock 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 Kane County, 28% of homes in mapped flood zones carry federal flood insurance, and 0.4% of all homes do.
How much is flood insurance in Big Rock?
FEMA’s Community Rating System list shows no discount for Big Rock’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 Big Rock?
By FEMA money that reached Big Rock, Severe Storms, Straight-line Winds, and Flooding (2013): 3 households applied for aid, $8K approved.
Is Big Rock at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (81%), and Big Rock’s rate for it is lower than 53% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Big Rock.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Big Rock’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.