About FloodRiskData
Is your home in a flood zone?
What we do
FloodRiskData pulls FEMA flood-zone maps, NFIP claim history, and disaster declarations into a single address-level flood picture.
We focus on U.S. flood risk, NFIP claims, and disaster declarations. Every page on floodriskdata.org is built from OpenFEMA (the Federal Emergency Management Agency open-data portal), cited and linkable so readers can trace any number back to its source.
Who runs this
FloodRiskData is built and maintained by the FloodRiskData Team. We're a small group working on making public U.S. flood risk, NFIP claims, and disaster declarations data easier for non-specialists to read. If you have a correction, a data tip, or a question about how a number was derived, the contact email below reaches us directly.
Who this is for
FloodRiskData is built for home buyers, homeowners, real-estate agents, insurance shoppers, and risk managers.
Why this exists
Public data on U.S. flood risk, NFIP claims, and disaster declarations is technically free, but practically locked behind file formats, acronyms, and paywalled dashboards. FloodRiskDataexists to close that gap: take the raw federal and public-sector data, and turn it into pages a normal person can read in thirty seconds.
How we work
- Primary source only. We pull from OpenFEMA (the Federal Emergency Management Agency open-data portal) and cite the exact dataset and version on every page.
- No invented numbers. If a figure is not in the underlying public data, it does not appear on floodriskdata.org. We never generate synthetic statistics to fill gaps.
- Methodology, in plain English. We combine the OpenFEMA NFIP claims, flood-zone designations, and Disaster Declarations datasets to show, per county and ZIP, the historical claim count, average claim size, and current flood-zone map designations. Address-level lookup uses the FEMA National Flood Hazard Layer.
- Refreshed on a schedule. Refreshed approximately every two months to align with FEMA dataset updates.
- Corrections welcome. Readers flag issues all the time. When the source fixes a record, FloodRiskData follows.
Known limitations
NFIP claims reflect insured losses only — uninsured flood damage, historically 70-80 percent of losses, is not captured. FIRM flood-zone maps can be a decade or more out of date in rapidly developing areas; for insurance or lending decisions, consult a current elevation certificate.
Why FEMA flood data deserves a public-facing home
The Federal Emergency Management Agency (FEMA) publishes the National Flood Hazard Layer covering every mapped Special Flood Hazard Area in the United States, plus the National Flood Insurance Program (NFIP) claims dataset showing every paid flood-insurance claim by ZIP, county, and state since the program began. Together these are the federal record of where floods happen and how often, and the data is public and free.
The presentation problem is that FEMA’s portal is built for floodplain managers and insurance professionals. A homeowner asking whether their property sits in a flood zone, a renter weighing flood risk before signing a lease, or a journalist investigating climate-driven repeat-loss properties needs the same FEMA data presented as a per-ZIP and per-county page with the flood-zone designation, the NFIP claims history, and the disaster declaration history all on one screen. FloodRiskData builds that presentation layer.
How the pipeline pulls FEMA data
The pipeline pulls from the FEMA OpenFEMA Data Catalog on a monthly cadence, which covers most of the FEMA datasets that matter for consumer-facing flood risk pages. The Flood Hazard Layer itself updates on a slower cadence (FEMA remaps individual communities over a multi-year cycle), and the site notes the effective date of the flood-zone map on each county page. The NFIP claims dataset is updated more frequently and is the closer-to-real-time signal of flood loss.
A practical detail: NFIP claims data is for policies in force at the time of the flood. Properties without NFIP coverage are not represented in the claims data even if they flooded. For uninsured-property flood losses, county-level disaster-declaration counts are a useful supplement and are also shown on each county page.
Where flood data has caveats
Three caveats. First, the FEMA flood-zone designation reflects FEMA’s mapped expected 1-percent or 0.2-percent annual flood probability based on the most recent remap. In rapidly-changing watersheds (urban development changing runoff, climate shifts changing rainfall patterns), the mapped flood zone can lag the actual current flood risk by years. Several recent FEMA remap cycles have moved properties into higher-risk zones that were previously outside the Special Flood Hazard Area.
Second, NFIP claims undercount total flood losses for two reasons: properties without flood insurance show no claim even when flooded, and several high-loss states have meaningful surplus-lines flood-insurance markets that report separately from NFIP. The pages note the NFIP-specific scope.
Third, the flood-zone designation matters for federally-backed mortgage insurance requirements and for NFIP rates, but it does not by itself predict whether a specific property will flood in a specific event. Local elevation, the property’s specific drainage situation, and the type of flood (riverine, coastal, urban flash) all matter for individual-property risk. Every value links back to the originating FEMA dataset.
Independence
FloodRiskData is an independent publication. We are not funded, owned, or directed by any of the agencies, companies, or organizations that appear in our data. Hosting is paid for by advertising — see our Privacy Policy for details — and we do not take paid placements, sponsored rankings, or "remove-my-entry" fees.
History
FloodRiskData launched in 2026 as part of a small portfolio of independent public-data sites. It has been maintained and updated continuously since.
Contact
Tips, corrections, data-partnership questions, and press inquiries: hello@floodriskdata.org. More options on our contact page.