Property flood risk & FEMA determination
Enter any US address. Returns the regulatory FEMA flood-zone determination plus a graduated 0–100 flood-risk score fused from FEMA, USGS, NOAA and USACE public data.
Portfolio flood screening
Paste addresses (one per line) or upload a CSV. Every property gets a FEMA determination (SFHA yes/no — the mandatory-purchase trigger) and a graduated score. Export the scored table as CSV.
Portfolio summary appears here after scoring —
count by risk band and share in a Special Flood Hazard Area.
| Address | Zone | SFHA | BFE (ft) | Score | Band | Primary driver |
|---|
National flood-hazard map
FEMA National Flood Hazard Layer over the whole US. Click any point to score it.
1% (100-yr) SFHA
Coastal V/VE
0.2% (500-yr)
The basemap and the FEMA flood-zone overlay load from the live internet, so this
map is blank in an offline preview — open the deployed URL in a browser to see tiles.
Data sources
Every layer is authoritative, free US public data. This prototype queries them live.
| Layer | Source | What it provides | Cost | Cadence |
|---|
Score weights are a sound default and are not yet validated against FEMA
Risk Rating 2.0, First Street, or actuarial loss experience — flagged for validation before
any authoritative use. USGS legacy water APIs are being retired (Spring 2026); this build
targets the modern
api.waterdata.usgs.gov OGC API for real-time gage data.