Hydrologic provinces of Michigan

This report presents the results of a study by the U.S. Geological Survey, in cooperation with the Michigan Department of Natural Resources, Geological Survey Division, to describe the statewide hydrologic variations in Michigan's water resources. Twelve hydrologic provinces, which are based on similarities in aquifer lithology, yield, recharge, and ground-water- and surface-water-quality data, are described. The definition of statewide hydrologic characteristics and the delineation of hydrologic provinces improves the understanding of Michigan's water resources and provides a firm basis for realistic water-manangement decisions.

The 12 provinces identified areas where bedrock aquifers provide most of the potable ground water (five provinces), where glacial-deposit aquifers provide most of the potable ground water (three provinces), and where problems with water quantity and (or) quality have limited the use of ground water as a water supply (four provinces). Subprovinces are defined on the basis of regional surface-water flow directions toward each of the Great Lakes.