What percentage of people in SE WI get their potable water from these aquifers?

Answer 1

Based on the information from the Wisconsin Geologic and Natural History Survey below, there is a big report that will tell you what you need to know. The url of the pdf is at the bottom.

From http://www.uwex.edu/wgnhs/gw_se_wisc.htm:
"Groundwater of southeastern Wisconsin focus of joint report
The groundwater resources of southeastern Wisconsin—Kenosha, Milwaukee, Ozaukee, Racine, Walworth, Washington, and Waukesha Counties—are the focus of a report now available online. The 203-page document, by staff of the Southeastern Wisconsin Regional Planning Commission and the Wisconsin Geological and Natural History Survey in cooperation with the Wisconsin Department of Natural Resources, is in Adobe® Acrobat® PDF format. The report summarizes groundwater inventory and analyses conducted by the agencies, characterizes the groundwater resouces and their susceptibility to contamination, and describes the existing and potential sources of contamination."

Groundwater resources of southeastern Wisconsin can be viewed at