The Wisconsin Department of Natural Resources (WDNR) requires all private wells in areas serviced by public water supply to obtain a permit from the local Water Utility.
NR 810.16 Local well regulation program. Water suppliers for municipal water systems and communities served by a municipal water system, shall implement a program for the regulation of wells which are not part of the municipal water system and are located on premises served by the municipal water system. Regulation is required to prevent unused, unsafe and noncomplying wells from acting as vertical conduits for aquifer contamination or as sources of unsafe water that could enter the public water system through cross connection. Implementation shall be by local ordinance or utility rule. The ordinance or rule shall include:
(1) A requirement that all water supply wells that do not have valid operational permits issued pursuant to sub.(2), wells which are not routinely used, wells which are in noncompliance with ch. NR 812, or wells which test bacteriologically unsafe, shall be properly sealed and abandoned in accordance with ch. NR 812 by an established date not to exceed one year from date of connection to the public system, or date of discovery or construction.
(2) Provisions for a well operation permit renewable not less frequently than every 5 years that will allow retention and operation of wells which are safe and in compliance with ch. NR 812 with the limitation that the well shall be functional and the owner shall demonstrate a need for use. The permit shall require:
(a) That a minimum of one safe sample be taken prior to issuing or reissuing the permit to establish that the water is bacteriologically safe.
(b) That the well and pump system be evaluated by a licensed well driller or pump installer and certified to comply with ch. NR 812 subch.IV, prior to issuing the initial permit and no less than every 10 years afterwards.
(c) Prohibition of unapproved cross-connections between any private well and pump installations and the municipal water system.
(3) Written documentation of the well and pump inspection indicating compliance with ch. NR 812 requirements using standardized forms provided by the department.
(4) Submission of a copy of the well regulation ordinance or rule to the department.