Photo: Jeffrey Beall · CC BY 3.0More hazard damage per building is expected in Willowbrook than in 98% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Willowbrook gets a D− for hazard risk: higher expected damage per building than 98% of U.S. towns, #746 of 847 in California. Most of that expected damage is river and rain flooding (64%), then earthquakes (35%). Flood insurance has paid 2 claims here since 2003.
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 Willowbrook 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
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 Willowbrook’s grade
River and rain flooding is 64% of the building damage FEMA expects in Willowbrook, and Willowbrook’s rate of river and rain flooding damage is in the top 2% of U.S. census tracts. Earthquakes add 35%, at a rate in the top 5% of U.S. census tracts.
D− #746 of 847 in California; higher expected damage per building than 98% of U.S. towns (21,298).
Willowbrook’s residents live in 7 census tracts; FEMA’s figures are combined by where they live.
The typical California town has higher expected damage than 92% of U.S. towns; within the state, Willowbrook has more expected damage per building than 88% of California towns.
In dollars, FEMA expects about $11.0M a year in losses across Willowbrook: $9.0M to buildings, the rest to people and crops.
Does Willowbrook flood? Rarely: 2 flood claims since 2003
Every paid claim on a federal flood insurance policy in Willowbrook, from FEMA’s records: 0.3 per 1,000 homes, fewer than 94% of the 13,809 U.S. towns with a flood insurance record.
Willowbrook isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Los Angeles County.The storms Willowbrook remembers
None of the 40 disasters declared for Los Angeles County shows FEMA aid or repair money reaching Willowbrook itself in FEMA’s records, so these are its biggest flood-claim years.
- 20032 flood claims paidThe year of Wildfires, Flooding, Mudflow and Debris Flow Directly Related T, declared for Los Angeles County
Los Angeles County has had 40 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.
Also 44 FEMA wildfire suppression grants (Fire Management Assistance, not a disaster declaration) for fires in Los Angeles County, 2002–2025.
Old photos of Willowbrook after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Willowbrook archive →Willowbrook and its neighbors
Willowbrook is 5th of the 5 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 |
|---|---|---|---|
| Lynwood | Dmore damage than 88% | earthquakes | 12 |
| West Rancho Dominguez | Dmore damage than 93% | earthquakes | 1 |
| Compton | Dmore damage than 95% | earthquakes | 8 |
| Los Angeles | D−more damage than 96% | earthquakes | 1,980 |
| Willowbrook | D−more damage than 98% | 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 Willowbrook 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.
- 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 Willowbrook
Is Willowbrook at risk for natural disasters?
On FEMA’s National Risk Index, Willowbrook has higher expected damage per building than 98% of U.S. towns: D− for hazard risk, #746 of 847 in California. Most of the expected damage is river and rain flooding (64%) and earthquakes (35%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Willowbrook flood?
Flood insurance has paid 2 claims in Willowbrook since 2003, $29K in all, or 0.3 per 1,000 homes, fewer than 94% of U.S. towns with a flood insurance record.
Is Willowbrook 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 Los Angeles County, 33% of homes in mapped flood zones carry federal flood insurance, and 0.5% of all homes do.
How much is flood insurance in Willowbrook?
FEMA’s Community Rating System list shows no discount for Willowbrook’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
Is Willowbrook at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (64%), and Willowbrook’s rate for it is in the top 2% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Willowbrook.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Willowbrook’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.