Storms, floods and disasters in Alhambra Valley
Alhambra Valley isn’t graded for hazard risk: Alhambra Valley has 979 residents; we grade towns of 1,000 or more.
What Alhambra Valley 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
Landslides
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.
Does Alhambra Valley flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Alhambra Valley. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Alhambra Valley 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.The storms Alhambra Valley remembers
None of the 17 disasters declared for Contra Costa County shows FEMA aid or repair money reaching Alhambra Valley itself in FEMA’s records, so these are its biggest flood-claim years.
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.
Alhambra Valley and its neighbors
How expected damage per building compares across the town line. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Martinez | Dmore damage than 92% | earthquakes | 87 |
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 Alhambra Valley 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.
- Watch for new cracks, tilting trees or suddenly muddy streams after heavy rain.
- Stay off steep slopes in a downpour.
- Leave if you hear rumbling upslope.
- 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 Alhambra Valley
Is Alhambra Valley 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 Alhambra Valley?
FEMA’s Community Rating System list shows no discount for Alhambra Valley’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
Storm stories
Memories, warnings and help from neighbors in Alhambra Valley.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Alhambra Valley’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.