Users will be able to download one map file or one zipped 1:250,000 map folder (includes all available data, up to 128 map files) at a time. Select a data file or folder, then click the right mouse button to use the copy option.
These files are in UTM projection, NAD83 (includes re-projected NAD27 data and "updated" NAD83 data).
http://wetlands.fws.gov/downloads.htm
NWI Data feature code descriptions
http://www.nwi.fws.gov/atx/atx.html
The National Wetlands Inventory is now using an HTTP server. Users can download one map file or one zipped 1:250,000 map folder (includes all available data, up to 128 map files) at a time. Select a data file or folder, then click the right mouse button to use the copy option.
How do I find the folder containing the NWI map I need? NWI digital map data are organized in folders by USGS.
Download Shapedata(UTM NAD83) for single quads or Download 1:250,000 zipped file folders. These files are in UTM projection, NAD83 (includes reprojected NAD27 data and "updated" NAD83 data).
Download Personal Geodatabases (UTM NAD83) Updated NWI geodatabase files or new digital data for which there are no NWI hardcopy maps. Examples available.
Download ARC data (UTM NAD27) for single quads or download 1:250,000 zipped file folders.
Download Updated ARC data (UTM NAD83) for single quads or download 1:250,000 zipped file folders.
Download seamless NWI Wetlands data
The most current NWI Wetlands data can be downloaded only through the new Wetlands Mapper download function. Only features from the ‘Interactive Layers’ that are visible in the current map frame or those features that are selected within the map frame can be downloaded.
http://wetlandsfws.er.usgs.gov/wtlnds/