As a result of a bill passed by the Wisconsin State Legislature in 1945, ground-water investigations in Wisconsin have been under way since February 1946 under the terms of an agreement between the U. S. Geological Survey and the University of Wisconsin. Pumping tests on wells that yield water from the Ordovician and Cambrian sandstones underlying the Milwaukee-Waukesha area have been made as a part a larger regional investigation. The purpose of the tests has been to determine the water-bearing characteristics of the aquifer. These characteristics, the coefficients of transmissibility and storage, are used to determine the effect on water levels caused by changes in the rate of withdrawal from the aquifer. Average coefficients of transmissibility and storage determined from the results of 47 pumping tests at five different locations are 23,800 gallons a day per foot, and 0.00039, respectively. The amount of drawdown in the water level at any point caused by pumping a well for a given length of time may be computed by the nonequilibrium formula, using the coefficients and correcting for the effects of boundaries and of any changes in the character of the aquifer. Further study of the geology is needed to determine the location of the recharge area, the location of possible boundaries, and changes in the character of the aquifer. Collection of water-level and pumpage data is continuing and will serve as a check of the computations using the coefficients of transmissibility and storage.
Additional Publication Details
USGS Numbered Series
Results of pumping tests on artesian wells in the Milwaukee - Waukesha area, Wisconsin