This is a ground-water profile for Minnesota's Southeast Region, which is comprised of Dodge, Fillmore, Freeborn, Goodhue, Houston, Mower, Olmsted, Rice, Steele, Wabasha and Winona Counties. Layered sandstone and carbonate bedrock aquifer systems are highly productive and of high natural quality. Extensive near-surface karst areas result in aquifers that are highly vulnerable to contamination. Glacial aquifers are not widely present and are often of moderate to poor yield. Isolated well interference problems are present.
Pesticides occur in older, shallow wells constructed in karst aquifers.
Nitrate contamination in near-surface aquifers is widespread. More water quality work is done here than in other regions, but there is a great need to better integrate local and state monitoring. The effects of implementing best management practices and other pollution control measures need to be assessed. The effectiveness of clay-rich glacial deposits in protecting bedrock aquifers needs to be determined. Define areas where nitrate concentrations approach or exceed health limits.