FEMA expects more hazard damage per building in South San Gabriel than in 95% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, South San Gabriel gets a D− for hazard risk: higher expected damage per building than 95% of U.S. towns, #571 of 847 in California. Most of that expected damage is river and rain flooding (56%), then earthquakes (43%). 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 South San Gabriel 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 South San Gabriel’s grade
River and rain flooding is 56% of the building damage FEMA expects in South San Gabriel, and South San Gabriel’s rate of river and rain flooding damage is in the top 7% of U.S. census tracts. Earthquakes add 43%, at a rate in the top 5% of U.S. census tracts.
D− #571 of 847 in California; higher expected damage per building than 95% of U.S. towns (21,298).
South San Gabriel’s residents live in 3 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, South San Gabriel has more expected damage per building than 67% of California towns.
In dollars, FEMA expects about $3.8M a year in losses across South San Gabriel: $3.2M to buildings, the rest to people and crops.
Does South San Gabriel flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in South San Gabriel. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
South San Gabriel 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 South San Gabriel remembers
None of the 40 disasters declared for Los Angeles County shows FEMA aid or repair money reaching South San Gabriel itself in FEMA’s records, so these are its biggest flood-claim years.
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.
South San Gabriel and its neighbors
South San Gabriel is 3rd of the 4 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 |
|---|---|---|---|
| Montebello | Dmore damage than 94% | earthquakes | 2 |
| Monterey Park | Dmore damage than 94% | river and rain flooding | 6 |
| South San Gabriel | D−more damage than 95% | river and rain flooding | 0 |
| Rosemead | D−more damage than 98% | river and rain flooding | 1 |
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 South San Gabriel 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 South San Gabriel
Is South San Gabriel at risk for natural disasters?
On FEMA’s National Risk Index, South San Gabriel has higher expected damage per building than 95% of U.S. towns: D− for hazard risk, #571 of 847 in California. Most of the expected damage is river and rain flooding (56%) and earthquakes (43%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Is South San Gabriel 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 South San Gabriel?
FEMA’s Community Rating System list shows no discount for South San Gabriel’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
Is South San Gabriel at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (56%), and South San Gabriel’s rate for it is in the top 7% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in South San Gabriel.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where South San Gabriel’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.