Groundwater recharge in Wisconsin--Annual estimates for 1970-99 using streamflow data

http://pubs.usgs.gov/fs/2009/3092/

The groundwater component of streamflow is important because it is indicative of the sustained flow of a stream during dry periods, is often of better quality, and has a smaller range of temperatures, than surface contributions to streamflow.

by Gebert, Warren A.; Walker, John F.; and Hunt, Randall J.

U.S. Geological Survey Fact Sheet 2009-3092

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