Obsidian Cliff · Photo: USGS · Public domainStorms, floods and disasters in Mammoth
Mammoth isn’t graded for hazard risk: Mammoth has 62 residents; we grade towns of 1,000 or more.
What Mammoth 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.
Does Mammoth flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Mammoth. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Mammoth isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Park County.The storms Mammoth remembers
None of the 2 disasters declared for Park County shows FEMA aid or repair money reaching Mammoth itself in FEMA’s records, so these are its biggest flood-claim years.
Park County has had 2 natural disasters declared by the President since 1953, most often floods.
Get ready for what Mammoth 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 Mammoth
Is Mammoth 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 Park County, 3% of homes in mapped flood zones carry federal flood insurance, and 0.2% of all homes do.
How much is flood insurance in Mammoth?
FEMA’s Community Rating System list shows no discount for Mammoth’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 Mammoth.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Mammoth’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.