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WhAEM and GFLOW BBM Files: U.S.

This model is distributed by EPA as a legacy model, but no user support is available from EPA.

Binary base map (BBM) files are vectorized graphics derived from U.S. Geological Survey (USGS) digital line graphs. BBM files can be imported directly into WhAEM and GFLOW software and serve as the geographic basis for groundwater modeling. To find BBM data for a specific geographic area, click on the appropriate state below. A more detailed graphic of the state you selected will display. Alternatively, you can choose from an alphabetical text list of available states.

Click on a state shaded green 

Alabama | Arizona | Arkansas | California (North) | California (South) | Colorado | Connecticut, Massachusetts, Rhode Island | Florida | Georgia | Idaho | Illinois | Indiana | Iowa | Kansas | Kentucky | Louisiana | Maine | Maryland, Delaware, Distr. of Columbia | Michigan (Lower Peninsula) | Michigan (Upper Peninsula) | Minnesota | Mississippi | Missouri | Montana | Nebraska | Nevada | New Hampshire, Vermont | New Jersey | New Mexico | New York | North Carolina | North Dakota | Ohio | Oklahoma | Oregon | Pennsylvania | South Carolina | South Dakota | Tennessee | Texas (West) | Texas (East) | Utah | Virginia | Washington | West Virginia | Wisconsin | Wyoming

Note that the WHAEM and GFLOW Binary Base Maps (BBM)s do not automatically unzip while using Windows Explorer in Windows. This is caused by an older zip program that is not 64-bit compatible. Unzip the BBM files manually by right clicking on the file and extracting the files using Windows.  Contact the help desk if you need your section of BBMs recreated as 64-bit compatible zip files.

Mention of trade names or commercial products does not constitute endorsement.

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Last updated on November 19, 2025
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