Roughly 70% of Kewaunee County rely on groundwater for their drinking water. The unique geology and soils of Kewaunee County present extreme challenges in protecting groundwater. The upper layer of bedrock is a type of rock that is easily dissolved by water. Extensive networks of vertical and horizontal fractures (cracks) in the bedrock are continuously forming.
Sinkholes, fracture traces (pictured to the right) disappearing streams, and caves are visible examples of places where bedrock has dissolved. These features often become direct conduits for transporting contaminants from the surface, such as sediment, chlorides, nitrates, bacteria and other microorganisms to groundwater aquifers.
As a homeowner with a private well, it is your responsibility to have your water tested regularly and to know it is safe to drink. It is recommended that all private wells be tested at least once per year for coliform bacteria and nitrates and more often if changes in water taste, odor or color are noticed. You may benefit from more frequent testing to detect seasonal or weather-related trends. There may be additional tests for you to conduct, based on activities around you, or if prior test results indicate that your well is vulnerable to contamination.
Next Well Testing Date: October 2022
- Homeowners Package (Coliform Bacteria, nitrate, chloride, pH, alkalinity, hardness, corrosibity index, conductivity)
- Metals Package (Arsenic, Calcium, Copper, Iron, Lead, Magnesium, Manganese, Potassium, Sulfate, Sodium, Zinc)
- Diaminochlorotriazine (DACT) (breakdown of atrazine and related herbicides)
Coastal Management Final Presentation 2021 (PDF) is under Documents & Files
- The 2007 Northeast Wisconsin Karst Task Force Final Report identified that less than 5 to carbonate bedrock, and or closed depressions or any drainage areas that contribute water to sinkholes/bedrock openings as an “extreme” relative vulnerability to contamination; 5-15 feet to carbonate bedrock as “high”; 15-50 as “significant”; and greater than 50 feet to carbonate bedrock as a “moderate” vulnerability.
- DNR Groundwater Collaboration Workgroups: Given the unique hydrogeology in certain regions of the state, specifically the karst geology in northeast Wisconsin, the Department of Natural Resources facilitated a groundwater work group to assess issues regarding landspreading and contamination of groundwater and drinking water wells.
- Dragun Nitrate Isotope Testing in Village of Casco (under Documents & Files)