Hydrologic Unit Maps

U.S. Geological Survey, Water Supply Paper 2294

by Paul R. Seaber, F. Paul Kapinos, and George L. Knapp

Table of Contents



History and development

Description of the hydrologic units

Hydrologic unit codes

Hydrologic unit names

Description of the Hydrologic Unit Maps

Compilation guidelines

Basic criteria

Technical criteria

Additional specifications

Coastal boundaries

Code identification

Digitized units

Drainage areas

Review and approval

Conflicts regarding boundaries

Maintenance and updating


National Water Data Network

Cataloging and coordinating data

Other uses of Hydrologic Unit Maps


Selected bibliography





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