Well Construction

Private wells have been regulated in Wisconsin since 1936. While the regulations and laws have changed and expanded since the original regulations were written, the intent of providing safe drinking water remains the same. The most controllable aspect of groundwater quality is how we construct the wells used to access this resource. Only licensed professionals are able to install wells in the State of Wisconsin, but property owners can work with these professionals to get the best results possible from wells on their property.

Well depth is often thought of as the biggest factor in reducing the amount of contaminants in a private well. While it is true that deeper wells often have lower nitrate levels, simply increasing depth is not always necessary to provide safe water to a home.  A larger influence can come from the depth of the well casing in relation to the static water level (SWL). The SWL is the top of the water table or the depth to water when the well is not pumping. The graph below shows data provided by the Wisconsin Department of Natural Resources for Dunn County. This data shows the nitrate concentrations in relation to how far passed the SWL the well casing ends. Positive numbers signify that the casing is terminated into the water table and negative numbers signify where the casing ends above the top of the water table.

People interested in learning more about the well on their property may find well construction reports at: https://dnr.wi.gov/WellConstructionSearch/#!/PublicSearch/Index