Hydrogeology of southwestern Sheboygan County, Wisconsin, in the vicinity of the Kettle Moraine Springs fish hatchery

This report describes the hydrogeology of the dolomite aquifer of Silurian age and its relation to springs in a study area in southwestern Sheboygan County, Wisconsin. The study was conducted at the Kettle Moraine Springs fish hatchery in cooperation with the Wisconsin Department of Natural Resources.

The dolomite aquifer is overlain by more than 60 feet of glacial deposits. Fine-grained glacial deposits confine the dolomite aquifer in the lowland at the hatchery. Thicker, coarse-grained glacial deposits overlie the dolomite aquifer on the hills surrounding the hatchery. The coarse-grained deposits are in good hydraulic connection with the aquifer.

The transmissivity and storage coefficient of the dolomite aquifer are 1,220 feet squared per day and 0.0007, respectively. Pumping from the aquifer results in drawdown in wells open to the aquifer and the effects of this pumping will decrease the greater the distance between wells. The amount of drawdown caused by pumping was estimated by means of distance-drawdown curves.

Five springs and two wells open to the dolomite aquifer supply water to the hatchery. Groundwater withdrawals from fish hatchery wells affect the water level in an observation well near the springs and probably decrease the flow from the springs to the hatchery. Additional pumping from the aquifer probably will further decrease flow from the springs.