Natural hazards · Seneca

Seneca, IL natural hazards

Most of the natural-hazard damage FEMA expects in Seneca comes from inland flooding, and overall the risk is moderate for a U.S. community. Flood insurance has paid 3 claims here since 2007.

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

Expected damage

How exposed is Seneca?

Moderate

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Seneca to be higher than in 41% of U.S. communities, mostly from inland flooding and tornadoes.

Inland flooding63%Tornadoes16%Cold waves14%Everything else7%

By hazard

What Seneca faces

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

Inland flooding

63% of expected damage

Above average · higher than 64% of U.S. places

Recorded about once a year in the area

Tornadoes

16% of expected damage

Well above average · higher than 83% of U.S. places

Recorded about once every 22 years in the area

Cold waves

14% of expected damage

Below average · higher than 31% of U.S. places

Recorded about 6 times a year in the area

Lower here

HurricanesHailIce stormsWinter weatherHeat wavesWildfireEarthquakesLandslidesStrong windLightningDrought

Not a risk here

Coastal floodingAvalanchesTsunamisVolcanic 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 Seneca flood?

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

3paid claims since 2007

$37Kpaid to owners

0homes flooded more than once

20072026

of homes in flood zones
are insured

of all homes
are insured

No community discount. Seneca isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.

Insurance rates: McHenry County.

Disasters that hit Seneca

Federal disasters declared here

None of the disasters declared for McHenry County shows FEMA aid or repair money reaching Seneca itself in FEMA’s records.

Brought FEMA money into SenecaDeclared for McHenry County only

McHenry County has had 14 natural disasters declared since 1953, most often winter storms and floods.

Around Seneca

Seneca and the towns around it

Very lowLowModerateHighVery high

Coralmostly inland floodingModerate

Senecamostly inland floodingModerate

Marengomostly inland floodingModerate

Rileymostly inland floodingLow

Hartlandmostly inland floodingVery low

Dorrmostly inland floodingVery low

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. Seneca covers 1 census tract, combined by population.

Money that reached townFlood claims are matched to Seneca’s own flood-insurance community (here, the census tracts inside it); household aid to the registrant’s city; repair grants to the Township of Seneca. 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 Seneca total about $4.6M 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.