Improperly Abandoned Or Improperly Constructed Wells

Water wells can be conduits for contaminants to reach groundwater via corroded or ruptured casings, abandonment, or where surface casings were inadequately sealed to prevent surface pollutants from entering the well. Improperly abandoned wells pose a major threat to groundwater because they channel contaminated surface or soil water directly into the groundwater. Surface water drainage wells, which are illegal in Wisconsin, drain surface water from wet fields into the ground and allow pollutants to reach groundwater.

While it is impossible to know how many improperly abandoned wells there may be in any given area WDNR estimates that there are over 100,000 wells statewide no longer in use and not properly sealed.

WDNR administrative rules NR 811.17 and NR 812.26 govern the proper abandonment of public and private water supply wells, respectively. For information regarding proper well abandonment contact the WDNR water supply specialist in the regional offices.

For more information on groundwater, visit the WDNR - Drinking Water and Groundwater Program