Information on the NHD is available at the USGS National Hydrography Dataset website.
A NHD User Guide, which includes interactive tutorials, feature catalog, and a video library, is located at this USGS National Hydrography Dataset website.
Information on the hydrography data product and model is available at the USGS The National Map Hydrography website.
Review the Download user guide at 9.0 - The Cart Tab and Product Download.
Data is currently available in Esri File Geodatabase format (9.3.1 or 10.1) or Shapefile.
Yes, but you must specify 'Dynamic Extract' in the Hydrography product list of the USGS Available Data window. Otherwise, pre-staged NHD Subregion data are available only in Personal or File Geodatabase formats. Also, file size limitations prevent any '...
Is NHD planned to be packaged in other ways than Subregion (second level, 4-digit hydrologic units)?
Not at this time, but USGS is investigating new rules for packaging its data.
NWI data is available in the Content sub-tab under Overlays in a panel called Other Featured Data along the left-hand side of The National Map Viewer. NWI data layers are provided by the U.S. Fish & Wildlife Service (FWS) through their Wetlands and...
Flow tables are not included in either staged State or Subregion NHD data because very large datasets may exceed an internal two GB processing limit. However, you can process the NHD data and build flow tables locally on your computer. First, download...