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Kansas Water Science Center

U.S. Geological Survey
Open-File Report 03–263

Base-Flow Index Grid for the Conterminous United States

By David M. Wolock


This 1-kilometer raster (grid) dataset for the conterminous United States was created by interpolating base-flow index (BFI) values estimated at U.S. Geological Survey (USGS) streamgages. Base flow is the component of streamflow that can be attributed to ground-water discharge into streams.

Wolock, D.M., 2003, Base-flow index grid for the conterminous United States: U.S. Geological Survey Open-File Report 03–263, digital data set, available on World Wide Web at URL

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For additional information contact:

David Wolock
U.S. Geological Survey
4821 Quail Crest Place
Lawrence, KS 66049-3839
Telephone: (785) 832-3528
Fax: (785) 832-3500