Photo: Unknown author · Public domainOn FEMA’s figures, Bostonia faces more hazard damage per building than 81% of U.S. towns, mostly from river and rain flooding
On FEMA’s National Risk Index, Bostonia gets a C− for hazard risk: higher expected damage per building than 81% of U.S. towns, #182 of 847 in California. Most of that expected damage is river and rain flooding (76%), then earthquakes (24%). Flood insurance has paid 4 claims here since 1981.
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 Bostonia 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 Bostonia’s grade
River and rain flooding is 76% of the building damage FEMA expects in Bostonia, and Bostonia’s rate of river and rain flooding damage is higher than 84% of U.S. census tracts. Next is earthquakes at 24% (higher than 85% of U.S. census tracts).
C− #182 of 847 in California; higher expected damage per building than 81% of U.S. towns (21,298).
Bostonia’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, Bostonia has less expected damage per building than 79% of California towns.
In dollars, FEMA expects about $4.4M a year in losses across Bostonia: $3.9M to buildings, the rest to people and crops.
Does Bostonia flood? Rarely: 4 flood claims since 1981
Every paid claim on a federal flood insurance policy in Bostonia, from FEMA’s records: 0.7 per 1,000 homes, fewer than 86% of the 13,809 U.S. towns with a flood insurance record.
Bostonia isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: San Diego County.The storms Bostonia remembers
None of the 30 disasters declared for San Diego County shows FEMA aid or repair money reaching Bostonia itself in FEMA’s records, so these are its biggest flood-claim years.
- 20162 flood claims paidNo declaration for the county that year
- 19811 flood claims paidNo declaration for the county that year
- 19831 flood claims paidThe year of Coastal Storms, Floods, Slides and Tornadoes, declared for San Diego County
San Diego County has had 30 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 18 FEMA wildfire suppression grants (Fire Management Assistance, not a disaster declaration) for fires in San Diego County, 2002–2018.
Old photos of Bostonia after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Bostonia archive →Bostonia and its neighbors
Bostonia is 2nd of the 4 graded towns here, from least expected damage per building to most. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| El Cajon | C−more damage than 80% | river and rain flooding | 26 |
| Bostonia | C−more damage than 81% | river and rain flooding | 4 |
| Winter Gardens | Dmore damage than 86% | river and rain flooding | 20 |
| Santee | Dmore damage than 91% | river and rain flooding | 5 |
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 Bostonia 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 Bostonia
Is Bostonia at risk for natural disasters?
On FEMA’s National Risk Index, Bostonia has higher expected damage per building than 81% of U.S. towns: C− for hazard risk, #182 of 847 in California. Most of the expected damage is river and rain flooding (76%) and earthquakes (24%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Bostonia flood?
Flood insurance has paid 4 claims in Bostonia since 1981, $25K in all, or 0.7 per 1,000 homes, fewer than 86% of U.S. towns with a flood insurance record.
Is Bostonia 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 San Diego County, 24% of homes in mapped flood zones carry federal flood insurance, and 0.7% of all homes do.
How much is flood insurance in Bostonia?
FEMA’s Community Rating System list shows no discount for Bostonia’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
Is Bostonia at risk from river and rain flooding?
It is the largest share of the building damage FEMA expects here (76%), and Bostonia’s rate for it is higher than 84% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Bostonia.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Bostonia’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.