Natural hazards · Johnston

Johnston, SC natural hazards

Most of the natural-hazard damage FEMA expects in Johnston comes from inland flooding, and overall the risk is very low for a U.S. community. 2 federal disasters brought FEMA money into town.

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

Expected damage

How exposed is Johnston?

Very low

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Johnston to be higher than in 18% of U.S. communities, mostly from inland flooding and drought.

Inland flooding29%Drought19%Earthquakes12%Hurricanes9%Tornadoes8%Strong wind6%Everything else17%

By hazard

What Johnston faces

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

Inland flooding

29% of expected damage

Well below average · higher than 16% of U.S. places

Recorded about once every 7 years in the area

Drought

19% of expected damage

Recorded about 40 times a year in the area

Earthquakes

12% of expected damage

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

Hurricanes

9% of expected damage

Above average · higher than 72% of U.S. places

Recorded about once every 13 years in the area

Tornadoes

8% of expected damage

Above average · higher than 52% of U.S. places

Recorded about once every 22 years in the area

Strong wind

6% of expected damage

Well above average · higher than 85% of U.S. places

Recorded about 5 times a year in the area

Lower here

HailIce stormsWinter weatherCold wavesHeat wavesWildfireLandslidesLightning

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 Johnston flood?

FEMA's records show no paid flood insurance claims in Johnston.

of all homes
are insured

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

Insurance rates: Edgefield County.

Disasters that hit Johnston

2 federal disasters brought FEMA money here

Disasters the President declared that paid out in Johnston itself: aid to households, or repair grants to the Town of Johnston.

Brought FEMA money into JohnstonDeclared for Edgefield County only

2024

Hurricane Helene

1,555 households applied for aid $1.3M aid approved $7K to the Town of Johnston for repairs

2004

Severe Ice Storm

$27K to the Town of Johnston for repairs

Edgefield County has had 16 natural disasters declared since 1953, most often hurricanes and severe storms.

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. Johnston is smaller than a census tract, so it shares the figures of the tract around its center.

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

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.