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Methodology used to produce an encoded 1:100,000-scale digital hydrographic data layer for the Pacific Northwest

Water-Resources Investigations Report 94-4043

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Abstract

The U.S. Geological Survey (USGS) has produced a River Reach File data layer for the Pacific Northwest for use in water-resource management applications. The Pacific Northwest (PNW) River Reach Files, a geo-referenced river reach data layer at 1:100,000-scale, are encoded with the U.S. Environmental Protection Agency"s (EPA) reach numbers. The encoding was a primary task of the River Reach project, because EPA"s reach identifiers are also an integral hydrologic component in a regional Northwest Environmental Data Base-an ongoing effort by Federal and State agencies to compile information on reach-specific resources on rivers in Oregon, Idaho, Washington, and western Montana. A unique conflation algorithm was developed by the USGS to transfer the EPA reach codes and other meaningful attributes from the 1:250,000-scale EPA TRACE graphic files to the PNW Reach Files. The PNW Reach Files also were designed so that reach-specific information upstream or downstream from a point in the stream network could be extracted from feature attribute tables or from a Geographic Information System. This report documents the methodology used to create this 1:100,000-scale hydrologic data layer.

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Methodology used to produce an encoded 1:100,000-scale digital hydrographic data layer for the Pacific Northwest
Series title:
Water-Resources Investigations Report
Series number:
94-4043
Edition:
-
Year Published:
1996
Language:
ENGLISH
Publisher:
U.S. Geological Survey ; Branch of Information Services [distributor],
Description:
iii, 84 p. :ill. ;28 cm.