National flood risk layer | FEMA.gov
The National Flood Hazard Layer (NFHL) is a geospatial database that contains current data on flood risk. FEMA provides flood risk data to support the national flood insurance program. You can use the information to better understand your flood risk level and the type of flooding.
The NFHL consists of effective flood maps and Map Modification Letters (LOMCs) delivered to communities. Numerical data from the NFHL covers more than 90 percent of the US population. New and revised data is constantly added. If you need information for areas not covered by the NFHL data, there may be other FEMA products that cover those areas.
Access the national flood risk layer
Cartographic Service Center
Access localized data from the National Flood Risk Layer by searching the FEMA Mapping Service Center.
FEMA Map Service Center
In the NFHL Viewer, you can use the address search or map navigation to locate an area of interest and the NFHL Print Tool to download and print a complete Flood Insurance Rate Map (FIRM) or FIRMette (a smaller, printable version of an FIRM) where modernized data exists. Technical GIS users can also use a series of dedicated GIS web services that allow the NFHL database to be integrated into GIS websites and applications. For more information on the services available, visit NFHL GIS Services User Guide.
You can also use the address search on the FEMA Flood Map Service Center (MSC) to consult the NFHL data or download an FIRMette. Using the “Find All Products” feature on the MSC, you can download NFHL data for a county or state in a GIS file format. This data can be used in most GIS applications to perform spatial analyzes and for integration into custom maps and reports. To do this, you will need a GIS or mapping software capable of reading data in shapefile format.
FEMA also offers the download of a KMZ (Zipped Keyhole Markup File) file, which overlay the data in Google Earth ™. For more information on data usage in Google Earth ™, please see Using the National Flood Risk Layer Web Map Service (WMS) in Google Earth ™.
National flood risk layer project
the National flood risk layer project is intended for an early awareness of possible changes in regulatory information on flood maps. Until the data becomes effective and appears in the national flood risk layer, the data cannot be used to assess flood insurance policies or enforce the federal purchase requirement. obligatory.
Preliminary data on flood risks
Preliminary flood risk data provides the public with a quick snapshot of their home or community’s projected risk to flood risk. Preliminary data may include new or revised Flood Insurance Rate Maps (FIRM), Flood Insurance Study Reports (FIS), and FIRM databases. View preliminary data on your community’s flood risk.
Awaiting flood risk data
Pending flood risk data provides the public with a quick snapshot of their home or community’s projected risk to flood risk. Pending data may include new or revised Flood Insurance Rate Maps (FIRM), Flood Insurance Study Reports (FIS), and FIRM databases. View preliminary data on your community’s flood risk.
Make official decisions
The NFHL database and GIS services can be used in maps or applications that combine NFHL flood risk data with basemaps and other reference data from other sources. However, to use NFHL data for official purposes, you are responsible for ensuring that the base map data meets FEMA standards for accuracy and that the locations depicted are interpreted correctly. the NFHL Viewer provides a default basemap that meets minimum standards.
For details of FEMA’s policy on the use of digital flood risk data for NFIP purposes, see Standards 147, 148, 149, 605, and 606 in the FEMA Policy Standards for NFIP. flood risk analysis and mapping.