Natural hazards · San Marcos

San Marcos, CA natural hazards

Most of the natural-hazard damage FEMA expects in San Marcos comes from inland flooding, and overall the risk is high for a U.S. community. Flood insurance has paid 18 claims here since 1978. 5 federal disasters brought FEMA money into town.

FEMA National Risk Index, December 2025 · OpenFEMA claims, aid & declarations

Expected damage

How exposed is San Marcos?

High

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in San Marcos to be higher than in 66% of U.S. communities, mostly from inland flooding and earthquakes.

Inland flooding68%Earthquakes21%Wildfire7%Everything else4%

By hazard

What San Marcos faces

Each hazard’s share of the damage FEMA expects here, and how that compares with the rest of the country.

Inland flooding

68% of expected damage

Well above average · higher than 77% of U.S. places

Recorded about 8 times a year in the area

Earthquakes

21% of expected damage

Well above average · higher than 82% of U.S. places

Wildfire

7% of expected damage

Well above average · higher than 95% of U.S. places

Lower here

HurricanesTornadoesHailWinter weatherHeat wavesLandslidesStrong windLightning

Not a risk here

Coastal floodingIce stormsCold wavesDroughtAvalanchesTsunamisVolcanic activity

Flood risk changes street by street. Check a specific address on FEMA’s flood map, and ask about flood insurance before you buy.

Flood insurance claims

Does San Marcos flood?

Every paid claim on a federal flood insurance policy in San Marcos, from FEMA’s records.

18paid claims since 1978

$356Kpaid to owners

1homes flooded more than once

19782026

Biggest named events

Pineapple Express - Southern: 2 claims, $38K
California Atmospheric River: 2 claims, $167K
Winter storm: 1 claim, $2K

Homes that flooded again and again

■ FEMA “severe repetitive loss” (0) ■ flooded 2+ times

of homes in flood zones
are insured

of all homes
are insured

No community discount. San Marcos 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.

Disasters that hit San Marcos

5 federal disasters brought FEMA money here

Disasters the President declared that paid out in San Marcos itself: aid to households, or repair grants to the City of San Marcos.

Brought FEMA money into San MarcosDeclared for San Diego County only

2024

Severe Storm and Flooding

20 households applied for aid $17K aid approved

2020

Wildfires

33 households applied for aid $3K aid approved

2007

Wildfires, Flooding, Mud Flows, and Debris Flows

66 households applied for aid $43 aid approved $97K to the City of San Marcos for repairs

2004

Severe Storms, Flooding, Debris Flows, and Mudslides

16 households applied for aid $11K aid approved

2003

Wildfires, Flooding, Mudflow and Debris Flow Directly Related T

5 households applied for aid $15K to the City of San Marcos for repairs

San Diego County has had 44 natural disasters declared since 1953, most often fires and floods.

Around San Marcos

San Marcos and the towns around it

Very lowLowModerateHighVery high

Lake San Marcosmostly inland floodingVery high

Escondidomostly inland floodingHigh

Elfin Forestmostly inland floodingHigh

Harmony Grovemostly inland floodingHigh

San Marcosmostly inland floodingHigh

Carlsbadmostly inland floodingModerate

Vistamostly inland floodingModerate

Encinitasmostly inland floodingModerate

About these numbers

How to read this page

An average, not a forecastFEMA’s National Risk Index estimates the damage 18 kinds of natural hazards cause in a typical year, from decades of records and models. A quiet decade can follow a bad year.

Compared by rate“Higher than N%” compares yearly damage as a share of what’s here, so a big city isn’t rated riskier just for having more buildings. San Marcos covers 17 census tracts, combined by population.

Money that reached townFlood claims are matched to San Marcos’s own flood-insurance community; household aid to the registrant’s city; repair grants to the City of San Marcos. FEMA’s model follows property values, so a place that recently lost many homes can rate lower than it feels.

FEMA’s expected losses across San Marcos total about $30.6M a year, counting buildings, people and crops.

Sources: FEMA National Risk Index (December 2025); 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. Census tracts: U.S. Census Bureau.