FEMA National Flood Hazard Layer
Effective flood hazard data and HEC-RAS models for NFIP
fema.gov
At a glance
- Region
- United States
- Coverage
- National flood hazard mapping
- Access
- Free
- Category
- Government
- Last updated
- 2025
What's inside
- Flood Insurance Studies
- Effective Models
- Cross Sections
- Flow Data
- FIRM Database
What you can do with it
Typical work that data of this type supports.
- 01
Hazard maps
Map flood-prone areas and who and what is exposed.
Because it has: Flood Insurance Studies
- 02
Model validation
Check flood models against observed events.
- 03
Response planning
Support evacuation, relief and insurance decisions.
Where AI adds value
Ideas for machine learning and AI agents built on this kind of data.
- 01
Flood extent from SAR
Segment flooded areas in radar imagery, even through cloud.
- 02
Depth estimates
Learn flood depth from terrain, rainfall and past events.
- 03
Early warning
Turn forecast ensembles into simple, local alerts.
Machine access and documentation
Open API
FEMA NFHL ArcGIS MapServer/WMS
Licence: US Government public domain
Listed in our registry of open water APIs, which WaterDataGPT can query live.
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