Hydrostratigraphy of West-Central Wisconsin: A New Approach to Groundwater Management

Recent studies in west-central Wisconsin and throughout the state, as well as in neighboring Minnesota , have highlighted the need for data relating to the hydrogeology of shallow carbonate rocks of the Trempealeau, Prairie du Chien, and Sinnipee groups in upland areas, and the effectiveness of low permeability bedrock as aquitards at shallow and deeper stratigraphic levels. These shallow stratigraphic units play an important, but poorly understood, role in controlling groundwater flow to deeper aquifers in Upper Cambrian sandstones and in sustaining baseflow to streams and springs throughout the region. Data on matrix porosity and permeability, the presence, abundance, and stratigraphic distribution of fractures and dissolution features, and the lateral continuity and hydraulic characteristics of low permeability zones are not readily available for Paleozoic bedrock in west-central Wisconsin . These types of data may be included in technical reports on file with regulatory agencies, Wisconsin DOT, and private consulting firms throughout the region. This project will compile and organize existing data from these and published sources on the geology and hydraulic properties of Cambrian-Ordovician strata throughout west-central Wisconsin into a searchable digital database. This project will also begin development of a new hydrostratigraphic framework for Cambrian-Ordovician bedrock in the region, and will serve as the starting point for development of a statewide digital database and hydrostratigraphic framework. Results of this project will be of interest to the hydrogeologic and regulatory community interested in the controls on groundwater recharge and flow, and the potential for migration of groundwater contaminants.