Southwest Wisconsin Groundwater and Geology study

Rural residents of Grant, Iowa, and Lafayette Counties in Wisconsin rely on private wells for their water.  Contaminants like nitrate and bacteria from septic systems, fertilizer, and manure can contaminate the groundwater that residents use.  Groundwater is vulnerable to contamination where the soil layer is thin and the bedrock is fractured, which is the case for much of the study region.  The SWIGG study includes five objectives that were designed to assess and understand private well water contamination in the three counties.

The SWIGG study tested water from hundreds of wells in Grant, Iowa, and Lafayette Counties to determine whether drinking water contamination issues exist, and if so, what is causing the contamination.

View/Download the final SWIGG study report SUMMARY

View/Download the final SWIGG study report (full version)

PowerPoint slides from the SWIGG Final Report presentations

SWIGG Related Resources

Update on the Southwest Wisconsin Groundwater and Geology Study – August 1, 2019
Press Release – July 29, 2019
Discussion of SWIGG Study Results – Darlington, WI – September 4, 2019
Press Release – June 5, 2019
SWIGG Fact Sheet / Handout
Press Release – 9/24/2018
Well Water Viewer
Private Wells Groundwater Quality

Other Resources and Information

Research on a Mysterious Cave Helps Lend Insight on Improving Water Quality
Bacterialogical Contamination of Private Wells
Improving your private well water quality
Water Quality in Iowa County (2 pages, 139 KB .pdf)
La calidad del agua para beber en el condado de Iowa (2 pages, 115 KB .pdf)
Central Wisconsin Groundwater Center
Groundwater in Iowa County — A Citizen’s Guide (31 p., 2,177 KB .pdf)
Groundwater recharge
Groundwater susceptibility
Springs in Iowa County
Water-table elevation
Protecting Wisconsin’s Groundwater Through Comprehensive Planning

Contact Information:

Grant County

Erik Heagle
608-723-6377, ext. 4


Iowa County

Katie Abbott


Lafayette County

Erica Sauer

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