Natural hazards · Walnut

Walnut, CA natural hazards

Most of the natural-hazard damage FEMA expects in Walnut comes from earthquakes, and overall the risk is very high for a U.S. community. Flood insurance has paid 3 claims here since 1980. 5 federal disasters brought FEMA money into town.

FEMA National Risk Index, December 2025 · OpenFEMA claims, aid & declarations

Expected damage

How exposed is Walnut?

Very high

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Walnut to be higher than in 87% of U.S. communities, mostly from earthquakes and inland flooding.

Earthquakes50%Inland flooding48%Everything else2%

By hazard

What Walnut faces

Each hazard’s share of the damage FEMA expects here, and how that compares with the rest of the country.

Earthquakes

50% of expected damage

Well above average · higher than 92% of U.S. places

Inland flooding

48% of expected damage

Well above average · higher than 88% of U.S. places

Recorded about 4 times a year in the area

Lower here

TornadoesHailWinter weatherHeat wavesWildfireLandslidesStrong windLightning

Not a risk here

Coastal floodingHurricanesIce stormsCold wavesDroughtAvalanchesTsunamisVolcanic activity

Flood risk changes street by street. Check a specific address on FEMA’s flood map, and ask about flood insurance before you buy.

Flood insurance claims

Does Walnut flood?

Every paid claim on a federal flood insurance policy in Walnut, from FEMA’s records.

3paid claims since 1980

$1Kpaid to owners

0homes flooded more than once

19802026

of homes in flood zones
are insured

of all homes
are insured

No community discount. Walnut 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.

Disasters that hit Walnut

5 federal disasters brought FEMA money here

Disasters the President declared that paid out in Walnut itself: aid to households, or repair grants to the City of Walnut.

Brought FEMA money into WalnutDeclared for Los Angeles County only

2025

Wildfires and Straight-Line Winds

59 households applied for aid $460 aid approved

2020

Wildfires

5 households applied for aid

2005

Severe Storms, Flooding, Landslides, and Mud and Debris Flows

$24K to the City of Walnut for repairs

2004

Severe Storms, Flooding, Debris Flows, and Mudslides

11 households applied for aid $400 aid approved $110K to the City of Walnut for repairs

2003

Wildfires, Flooding, Mudflow and Debris Flow Directly Related T

2 households applied for aid

Los Angeles County has had 74 natural disasters declared since 1953, most often fires and floods.

Around Walnut

Walnut and the towns around it

Very lowLowModerateHighVery high

Pomonamostly earthquakesVery high

Industrymostly earthquakesVery high

Walnutmostly earthquakesVery high

West Covinamostly earthquakesVery high

About these numbers

How to read this page

An average, not a forecastFEMA’s National Risk Index estimates the damage 18 kinds of natural hazards cause in a typical year, from decades of records and models. A quiet decade can follow a bad year.

Compared by rate“Higher than N%” compares yearly damage as a share of what’s here, so a big city isn’t rated riskier just for having more buildings. Walnut covers 7 census tracts, combined by population.

Money that reached townFlood claims are matched to Walnut’s own flood-insurance community; household aid to the registrant’s city; repair grants to the City of Walnut. FEMA’s model follows property values, so a place that recently lost many homes can rate lower than it feels.

FEMA’s expected losses across Walnut total about $18.5M a year, counting buildings, people and crops.

Sources: FEMA National Risk Index (December 2025); 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. Census tracts: U.S. Census Bureau.