FEMA expects more hazard damage per building in South Monrovia Island than in 96% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, South Monrovia Island gets a D− for hazard risk: higher expected damage per building than 96% of U.S. towns, #595 of 847 in California. Most of that expected damage is river and rain flooding (52%), then earthquakes (47%). 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 Monrovia Island 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 Monrovia Island’s grade
River and rain flooding is 52% of the building damage FEMA expects in South Monrovia Island, and South Monrovia Island’s rate of river and rain flooding damage is in the top 7% of U.S. census tracts. Earthquakes add 47%, at a rate in the top 4% of U.S. census tracts.
D− #595 of 847 in California; higher expected damage per building than 96% of U.S. towns (21,298).
South Monrovia Island’s residents live in 2 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 Monrovia Island has more expected damage per building than 70% of California towns.
In dollars, FEMA expects about $2.8M a year in losses across South Monrovia Island: $2.2M to buildings, the rest to people and crops.
Does South Monrovia Island flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in South Monrovia Island. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
South Monrovia Island 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 Monrovia Island remembers
None of the 40 disasters declared for Los Angeles County shows FEMA aid or repair money reaching South Monrovia Island 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 Monrovia Island and its neighbors
South Monrovia Island is 3rd of the 3 graded towns here, from least expected damage per building to most. 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 South Monrovia Island 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 Monrovia Island
Is South Monrovia Island at risk for natural disasters?
On FEMA’s National Risk Index, South Monrovia Island has higher expected damage per building than 96% of U.S. towns: D− for hazard risk, #595 of 847 in California. Most of the expected damage is river and rain flooding (52%) and earthquakes (47%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Is South Monrovia Island 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 Monrovia Island?
FEMA’s Community Rating System list shows no discount for South Monrovia Island’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
Is South Monrovia Island at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (52%), and South Monrovia Island’s rate for it is in the top 7% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in South Monrovia Island.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where South Monrovia Island’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.