Wis. Stat. § 94.27: Liability for damages.

Any person who builds or maintains any dam or constructs or keeps open any ditch or drain under s. 94.26 is liable to persons whose lands are overflowed or otherwise injured by the dam, ditch or drain for the full sum of damages sustained, which shall be ascertained under s. 94.28 and recovered under ss. 94.28 to 94.30.