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Using the National Flood Hazard Layer Web Map Service (WMS) in Google Earth™

Google Earth example Google Earth is a popular Internet application through which users can view maps. This web site provides zipped Keyhole Markup Language (.kmz) files through which users can view map overlays created from FEMA's National Flood Hazard Layer on Google Earth images.

You must already have the Google Earth application installed on your computer to use these files. The starting point for obtaining the software is http://earth.google.com. Information about the system requirements needed for your computer to run the software is available through http://earth.google.com/support. A user guide is available at http://earth.google.com/userguide.

FEMA offers two applications: "Stay Dry" and "FEMA NFHL." Each is described below, and each has its own .kmz file. For optimum performance, please do not open both, and do not have more than one copy of each, in Google Earth at the same time.

To use the .kmz files, first save them to your computer. Do this by right-clicking on a hyperlinked file name below, choosing "Save Target as" (Internet Explorer) or "Save Link As" (Firefox), changing the file name if you wish (be sure that the file name has the extension .kmz), and clicking on save.

After saving the file, double-click on the file on your computer. This action should start Google Earth and provide the opening view for the application.

If you plan to use mapped flood information displayed in Google Earth for official purposes, insure that imagery and other map information displayed with the flood data meet FEMA's standards for map accuracy.

Some Geographic Information System (GIS) software can import GIS data encoded in the kmz format used for these applications. This technique is unlikely to work with the kmz files provided below. If you are interested in using the NFHL in GIS software, use the NFHL GIS data or NFHL Web Map Service. Both are available through FEMA's Map Service Center (MSC) at http://msc.fema.gov.

FEMA anticipates future improvements to the .kmz files, so please revisit this page occasionally to obtain the latest version.

Stay Dry

"Stay Dry" is a focused application that provides basic flood hazard map information from FEMA's National Flood Hazard Layer for an address. It allows you to view flood hazard zones, cross sections and their labels, community names and boundaries, Flood Insurance Rate Map numbers and boundaries, and Letter of Map Revision case numbers and boundaries.

For best performance please delete or turn off previous versions of the "Stay Dry" or "FEMA NFHL" folders that you have loaded in Google Earth before using the new version of "Stay Dry."

Stay_Dry_v2.0.kmz

Stay Dry Google Earth Application Instructions

Version 2.0 has one step, in which the user provides an address and receives a view of flood hazard information. Previous versions required two steps before flood hazard information could be viewed.

Please use version 2.0 instead of previous versions.

FEMA NFHL

"FEMA NFHL" is a general application that provides for the display of flood hazard zones, floodways, Coastal Barrier Resources System and Otherwise Protected Area units, community boundaries and names, base flood elevations, cross sections and coastal transects and their labels, hydraulic and flood control structures, and Flood Insurance Rate Map and Letter of Map Revision boundaries and numbers. Additional reference layers include the status of NFHL data availability, point locations for Letters of Map Amendment (LOMAs) and Letters of Map Revision Based on Fill (LOMR–Fs), Q3 base flood, and subbasin hydrologic units. You control the information displayed by turning layers on and off. A basic knowledge of Google Earth and FEMA flood hazard information will help users of this application.

The name of each layer is hyperlinked to a description of the layer, the map symbols used for the layer, and links to other FEMA web sites relevant to the layer. If a layer is turned on, clicking the text below the name of the layer (text that starts with "Draws at…") zooms the Google Earth view to a sample display of the layer. Layers are organized for display at one or more of three "eye altitude" (map scale) ranges in Google Earth: status maps and subbasins at high altitudes, regional overviews of flood hazards at medium altitudes, and detailed flood hazard maps at low altitudes. Click on the hyperlinked folder name of the application to see the altitudes at which data in the layers are displayed.

For best performance please delete or turn off previous versions of the "Stay Dry" or "FEMA NFHL" folders that you have loaded in Google Earth before using the new version of "FEMA NFHL."

FEMA_NFHL_v2.3.kmz

FEMA NFHL Google Earth Application Instructions

Changes for version 2.3 include:

  • A less intrusive way of providing the Welcome screen and quick-start instructions.
  • The combination overlay "Subbasins and Flood Events" renamed to "Subbasins and Flood Hazards."
  • Better description of the effects of double-clicking on the text below an overlay name (change in documentation).
  • New sample area for "Subbasins and Flood Hazards" that shows an entire subbasin.
  • All map images are the same resolution to prevent display interference among overlays.
  • Inserted a patch to refresh the status map when the view changes. (This change works around a bug in recent versions of the Google Earth viewer.)

Users of recent versions of the Google Earth viewer software should upgrade to version 2.3 to avoid the problem in which the status map does not refresh.