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Hydrologic unit codes and boundaries

Map showing various hydrologic units and their boundaries.

Georgia has river basins in:
  • Two regions
  • Nine subregions
  • 12 accounting units
  • 52 cataloging units
View lists of Georgia's hydrologic units
(New window) 		The hydrologic units shown on the map display represent natural and manmade stream-drainage areas (basins). These codes are used as administrative addresses of basins, and they do not necessarily represent natural watersheds.

Hydrologic Unit Boundary


Regions are the largest drainage basins delineated in the hydrologic-unit system. Subregions divide the regions, and they include the area drained by a river system, a closed basin(s), or a group of streams that form a coastal drainage area. Accounting units subdivide many of the subregions. Cataloging units are the smallest hydrologic subdivisions shown.

Hydrologic Unit Code

The hydrologic unit code is an eight-digit number that identifies each hydrologic unit. The code uniquely identifies each of the four levels—regional, subregional, accounting, and cataloging—of hydrologic classification within four two-digit fields.

This URL: http://nts4dgaatl.er.usgs.gov:80/HydroHelp/huccodes.cfm
Last updated: 01/05/2004 02:57:01 PM

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