Photo: en:User:JD Lisa · Public domainMore hazard damage per building is expected in Moraga than in 94% of U.S. towns, mostly from earthquakes
On FEMA’s National Risk Index, Moraga gets a D for hazard risk: higher expected damage per building than 94% of U.S. towns, #475 of 847 in California. Most of that expected damage is earthquakes (55%), then river and rain flooding (38%). Flood insurance has paid 2 claims here since 1982.
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 stands out about Moraga’s natural hazards
From FEMA’s model and FEMA’s records, below.
What Moraga faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
Earthquakes
River and rain flooding
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 Moraga’s grade
Earthquakes are 55% of the building damage FEMA expects in Moraga, and Moraga’s rate of earthquakes damage is in the top 4% of U.S. census tracts. Wildfire adds 6%, at a rate in the top 4% of U.S. census tracts.
D #475 of 847 in California; higher expected damage per building than 94% of U.S. towns (21,298).
Moraga’s residents live in 6 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, Moraga has more expected damage per building than 56% of California towns.
In dollars, FEMA expects about $15.9M a year in losses across Moraga: $13.1M to buildings, the rest to people and crops.
Does Moraga flood? Rarely: 2 flood claims since 1982
Every paid claim on a federal flood insurance policy in Moraga, from FEMA’s records: 0.3 per 1,000 homes, fewer than 93% of the 13,809 U.S. towns with a flood insurance record.
Moraga 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.4 federal disasters brought FEMA money to Moraga
Disasters that paid out in Moraga itself (aid to households or repair grants to the Town of Moraga), newest first, with that year’s flood claims.
- 2022Severe Winter Storms, Flooding, Landslides, and Mudslides72 households applied for aid$248K aid approved$660K to the Town of Moraga for repairs
- 2017Severe Winter Storms, Flooding, and Mudslides$20K to the Town of Moraga for repairs
- 2017Severe Winter Storms, Flooding, and Mudslides$23K to the Town of Moraga for repairs
- 2005Severe Storms, Flooding, Mudslides, and Landslides$988K to the Town of Moraga for repairs1 flood claim paid that year
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 Moraga after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Moraga archive →Moraga and its neighbors
Moraga has the lowest expected damage per building of the 3 graded towns here. Tap a town to see its hazards.
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 Moraga faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- 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.
- 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 Moraga
Is Moraga at risk for natural disasters?
On FEMA’s National Risk Index, Moraga has higher expected damage per building than 94% of U.S. towns: D for hazard risk, #475 of 847 in California. Most of the expected damage is earthquakes (55%) and river and rain flooding (38%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Moraga flood?
Flood insurance has paid 2 claims in Moraga since 1982, $11K in all, or 0.3 per 1,000 homes, fewer than 93% of U.S. towns with a flood insurance record.
Is Moraga 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 Moraga?
FEMA’s Community Rating System list shows no discount for Moraga’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 Moraga?
By FEMA money that reached Moraga, Severe Storms, Flooding, Mudslides, and Landslides (2005): $988K to the Town of Moraga for repairs.
Is Moraga at risk from earthquakes?
It is the largest share of the building damage FEMA expects here (55%), and Moraga’s rate for it is in the top 4% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Moraga.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Moraga’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.