Natural hazards · Reliez Valley

Reliez Valley, CA natural hazards

Most of the natural-hazard damage FEMA expects in Reliez Valley comes from earthquakes, and overall the risk is very high for a U.S. community.

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

Expected damage

How exposed is Reliez Valley?

Very high

vs. U.S. communities

FEMA expects yearly storm and flood damage to homes and buildings in Reliez Valley to be higher than in 86% of U.S. communities, mostly from earthquakes and inland flooding.

Earthquakes47%Inland flooding44%Wildfire5%Everything else4%

By hazard

What Reliez Valley faces

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

Earthquakes

47% of expected damage

Well above average · higher than 92% of U.S. places

Inland flooding

44% of expected damage

Well above average · higher than 81% of U.S. places

Recorded about once a year in the area

Wildfire

5% of expected damage

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

Lower here

TornadoesHailWinter weatherHeat wavesLandslidesStrong windLightningVolcanic activity

Not a risk here

Coastal floodingHurricanesIce stormsCold wavesDroughtAvalanchesTsunamis

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 Reliez Valley flood?

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

of homes in flood zones
are insured

of all homes
are insured

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

Insurance rates: Contra Costa County.

Disasters that hit Reliez Valley

Federal disasters declared here

None of the disasters declared for Contra Costa County shows FEMA aid or repair money reaching Reliez Valley itself in FEMA’s records.

Brought FEMA money into Reliez ValleyDeclared for Contra Costa County only

Contra Costa County has had 17 natural disasters declared since 1953, most often floods and severe storms.

Around Reliez Valley

Reliez Valley and the towns around it

Very lowLowModerateHighVery high

Lafayettemostly inland floodingVery high

Walnut Creekmostly earthquakesVery high

Pleasant Hillmostly earthquakesVery high

Martinezmostly earthquakesVery high

Reliez Valleymostly earthquakesVery high

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. Reliez Valley 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 Reliez Valley’s own flood-insurance community; household aid to the registrant’s city; repair grants to Reliez Valley. 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.