Drinking Water and Groundwater Quality in the Lower Wisconsin River Valley

The Lower Wisconsin River Valley (LWRV), from Prairie du Sac to Boscobel, is a broad level valley consisting of sandy soils over deep, coarse textured subsurface geological materials. Most of the drinking water in the LWRV comes from the shallow sand and gravel aquifer where depth to groundwater ranges from 5 to 15 feet. The exception to this is a relatively small area in the valley located north of the river near Byrds Creek and Eagle Corners on the Bridgeport Terrace where a Late Wisconsin loess cap is present (Knox and Attig, 1988). In this area the soils are deep and medium-textured; depth to water is generally 30-60 feet. The Wisconsin River is a regional, groundwater discharge point; groundwater flows from the flakes of the valley toward the river in a slight westerly direction, although locally streams and wetland areas may affect this flow pattern.