Wisconsin's Role in Great Lakes Restoration - American Water ...

14. A Hydrogeophysical Study of the Fox River South of Waukesha, WI
**Michael S. Baierlipp, Geosciences Department, UW-Milwaukee, Milwaukee WI,
baierli2@uwm.edu
William F. Kean, Geosciences Department, UW-Milwaukee, Milwaukee, WI,
wkean@uwm.edu
A geophysical study along the Fox River south of the city of Waukesha, Wisconsin is in
progress to help determine hydrologic properties of the glacially derived near surface
sediments. It is part of a larger study to determine the interaction between the groundwater
and surface water. Electromagnetic induction (EM) lines using a Geonics EM-31MK2 have
covered approximately 1.1 km of the river, and parts of the surrounding shoreline. Forty
electrical resistivity tomography (ERT) lines have been measured in the immediate area west
of the river, with two additional lines across the river. The ERT was completed using a GF
instruments Ares profiling system. The EM studies in the river have located two areas of low
electrical conductivity that suggest these areas are underlain by material of high hydraulic
conductivity such as gravel and sand. The ERT surveys are correlated with nearby lithologic
well logs and electrical well logs. The ERT surveys west of the river show dominantly east -
west regions of higher electrical resistivity that may be preferential groundwater pathways
providing a hydrologic connection between the river and the groundwater system.
** Graduate student presentation
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