EXAMPLES OF THE MINNESOTA GEOLOGICAL SURVEY’S ROLE IN PROVIDING INFORMATION REQUIRED FOR WATER RESOURCE MANAGEMENT

Land-use planning in Minnesota is largely directed towards preserving the state’s abundant but sensitive water resources. Increased pressures on these resources due to population growth have prompted land-use planners to address three broad and overlapping concerns: water quantity, water quality, and surface water–ground water interaction. The Minnesota Geological Survey (MGS), established as a source of sound geologic information for the state, is active in these concerns. This poster presents three examples of how MGS mapping products have evolved to assist an ever-broadening group of decision makers concerned with the management and protection of water resources. The northwestern Twin Cities metropolitan area is experiencing rapid growth towards the eroded edge of bedrock aquifers. In order to help the local Metropolitan Council determine the quantity of water available, MGS provided information on the extent, thickness, and hydraulic properties of bedrock aquifers in this area. Products included isopachs of aquifer thickness, borehole geophysical data, hydraulic data, and an updated water well database. Southeastern Minnesota consists of karst terrain where changing land-use practices may impact ground-water quality. MGS is participating in an Environmental Protection Agency 319 demonstration project to provide information on areas where bedrock aquifers are most susceptible to rapid recharge. Products include maps of bedrock geology, structure, and depth to bedrock, along with a karst features database. Surface water–ground water interaction is a concern of the Carnelian-Marine Watershed district in northern Washington County. MGS provided the district with a bedrock topography map, a surficial materials map showing areas of preferential recharge, digital elevation models of till layers, a water-table map, and an interpretive report. Decision makers need to have information that is easily available and understandable. Project results are provided digitally as customized Arcview projects. Associated databases are available online, and interpretive reports are typically combined with a users’ workshop. Our goal is to broaden the list of people who understand the importance of geology in land-use decisions.