Photo: Farragutful · CC BY-SA 4.0FEMA expects more hazard damage per building in Nanakuli than almost anywhere in the U.S., mostly from river and rain flooding
On FEMA’s National Risk Index, Nanakuli gets a D− for hazard risk: among the highest expected damage per building of U.S. towns, #77 of 93 in Hawaii. Most of that expected damage is river and rain flooding (56%), then tsunamis (24%). 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 Nanakuli 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
Tsunamis
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 Nanakuli’s grade
River and rain flooding is 56% of the building damage FEMA expects in Nanakuli, and Nanakuli’s rate of river and rain flooding damage is in the top 2% of U.S. census tracts. Tsunamis add 24%, at a rate in the top 1% of U.S. census tracts.
D− #77 of 93 in Hawaii; among the highest expected damage per building of U.S. towns (21,298).
Nanakuli’s residents live in 5 census tracts; FEMA’s figures are combined by where they live.
The typical Hawaii town has higher expected damage than 96% of U.S. towns; within the state, Nanakuli has more expected damage per building than 83% of Hawaii towns.
In dollars, FEMA expects about $7.2M a year in losses across Nanakuli: $6.7M to buildings, the rest to people and crops.
Does Nanakuli flood? No paid flood claims on record
FEMA’s records show no paid flood insurance claims in Nanakuli. That’s not a promise: most homes don’t carry flood insurance, so small floods go unrecorded.
Nanakuli isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Honolulu County.2 federal disasters brought FEMA money to Nanakuli
Disasters that paid out in Nanakuli itself (aid to households or repair grants to Nanakuli), newest first, with that year’s flood claims.
- 2026Severe Storms, Flooding, Landslides, and Mudslides1 households applied for aid$790 aid approved
- 2008Severe Storms and Flooding1 households applied for aid$7K aid approved
Honolulu County has had 18 natural disasters declared by the President since 1953, most often severe storms, then floods.
Also 4 FEMA wildfire suppression grants (Fire Management Assistance, not a disaster declaration) for fires in Honolulu County, 2005–2025.
Old photos of Nanakuli after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Nanakuli archive →Nanakuli and its neighbors
Nanakuli 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 |
|---|---|---|---|
| Nanakuli | D−among the highest damage | river and rain flooding | 0 |
| Maili | D−among the highest damage | river and rain flooding | — |
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 Nanakuli 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.
- Strong shaking or a sudden drop in the sea means head for high ground now.
- Learn the tsunami route signs near the shore.
- Stay away until officials say it’s safe.
- 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 Nanakuli
Is Nanakuli at risk for natural disasters?
On FEMA’s National Risk Index, Nanakuli has among the highest expected damage per building of U.S. towns: D− for hazard risk, #77 of 93 in Hawaii. Most of the expected damage is river and rain flooding (56%) and tsunamis (24%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Is Nanakuli 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 Honolulu County, 54% of homes in mapped flood zones carry federal flood insurance, and 4.1% of all homes do.
How much is flood insurance in Nanakuli?
FEMA’s Community Rating System list shows no discount for Nanakuli’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 Nanakuli?
By FEMA money that reached Nanakuli, Severe Storms and Flooding (2008): 1 households applied for aid, $7K approved.
Is Nanakuli at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (56%), and Nanakuli’s rate for it is in the top 2% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Nanakuli.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Nanakuli’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.