Photo: Boereck 14:52, 27 July 2006 (UTC) · CC BY-SA 3.0FEMA expects more hazard damage per building in Clayton than in 95% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Clayton gets a D for hazard risk: higher expected damage per building than 95% of U.S. towns, #553 of 847 in California. Most of that expected damage is river and rain flooding (61%), then earthquakes (30%). Flood insurance has paid 1 claim here since 1998.
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 Clayton 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
Wildfire
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 Clayton’s grade
River and rain flooding is 61% of the building damage FEMA expects in Clayton, and Clayton’s rate of river and rain flooding damage is in the top 6% of U.S. census tracts. Earthquakes add 30%, at a rate in the top 8% of U.S. census tracts.
D #553 of 847 in California; higher expected damage per building than 95% of U.S. towns (21,298).
Clayton’s residents live in 5 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, Clayton has more expected damage per building than 65% of California towns.
In dollars, FEMA expects about $9.7M a year in losses across Clayton: $8.8M to buildings, the rest to people and crops.
Does Clayton flood? Rarely: 1 flood claim since 1998
Every paid claim on a federal flood insurance policy in Clayton, from FEMA’s records: 0.3 per 1,000 homes, fewer than 96% of the 13,809 U.S. towns with a flood insurance record.
- The Pineapple Express - Southern1 claim · $750
Clayton isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Contra Costa County.1 federal disaster brought FEMA money to Clayton
Disasters that paid out in Clayton itself (aid to households or repair grants to the City of Clayton), newest first, with that year’s flood claims.
- 2022Severe Winter Storms, Flooding, Landslides, and Mudslides37 households applied for aid$89K aid approved$477K to the City of Clayton for repairs
Contra Costa County has had 17 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 Clayton after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Clayton archive →Clayton and its neighbors
Clayton 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 |
|---|---|---|---|
| Clayton | Dmore damage than 95% | river and rain flooding | 1 |
| Concord | D−more damage than 96% | river and rain flooding | 29 |
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 Clayton 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.
- Clear dead leaves and brush within 5 feet of the house.
- Sign up for local alerts and know two ways out.
- Keep N95 masks for smoky days.
- 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 Clayton
Is Clayton at risk for natural disasters?
On FEMA’s National Risk Index, Clayton has higher expected damage per building than 95% of U.S. towns: D for hazard risk, #553 of 847 in California. Most of the expected damage is river and rain flooding (61%) and earthquakes (30%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Clayton flood?
Flood insurance has paid 1 claim in Clayton since 1998, $750 in all, or 0.3 per 1,000 homes, fewer than 96% of U.S. towns with a flood insurance record. The most claims came from Pineapple Express - Southern (1).
Is Clayton 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 Contra Costa County, 28% of homes in mapped flood zones carry federal flood insurance, and 0.9% of all homes do.
How much is flood insurance in Clayton?
FEMA’s Community Rating System list shows no discount for Clayton’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 Clayton?
By FEMA money that reached Clayton, Severe Winter Storms, Flooding, Landslides, and Mudslides (2022): 37 households applied for aid, $89K approved, and $477K to the City of Clayton for repairs. By flood claims, Pineapple Express - Southern: 1 paid, $750.
Is Clayton at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (61%), and Clayton’s rate for it is in the top 6% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Clayton.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Clayton’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.