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USGS Gap Analysis Project Additional Data: Hydrologic Unit Codes [HUCs]

October 1, 2018

The Hydrologic Unit Code (HUC) is part of a hierarchical classification system for surface water drainage in the US (Seaber et al. 1987). The numerical code represents a cataloging unit of delineation. Vector format (i.e. polygon) data were compiled from United States Geological Survey (USGS) source - the Watershed Boundary Dataset (WBD). In order to include areas of large water bodies and ocean shorelines, an iterative process was used to expand polygons boundaries 5 kilometers extending from landward edges. This altered 12-digit code HUC dataset was used to delineate species ranges as part of the USGS Gap Analysis Project's species range and distribution modeling effort.

Citation Information

Publication Year 2018
Title USGS Gap Analysis Project Additional Data: Hydrologic Unit Codes [HUCs]
DOI 10.5066/F7DZ0754
Authors Rubino Matt, Williams Steve
Product Type Data Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Science Analytics and Synthesis