USGS Hydrologic Unit Codes

HUC Data Files

Drainage Basin Lookup Tables

HUC 2 is regional, HUC 4 is sub region, and HUC 6 is basin. These have headings of an ID number, lon and lat point, the HUC region number it belongs to (in either 2, 4, or 6 digits), the name of that region, the states which fall into that region, the shape length and area, and some more ID information. The lat/lon points outside the US are still included but do not have any other attributes associated with them.

The next 3 files include the lat/lon points that are joined to both the USGS divisions and the Canadian divisions in one large table. This data does have a different resolution than the USGS data, and was gathered from Natural Resources Canada. The column headings here are a little more complex so there is a "variable name" sheet within each of these files to keep track of them.