Wisconsin Statutes Highways (Ch. 80 to 86) § 82.37. Tunnel under highway by landowner

The owner of land on both sides of a town highway may construct a tunnel under the highway, and may erect fences that are necessary for the use of the tunnel. The tunnel shall not interfere with or endanger travel on the highway. The owner shall maintain the tunnel and shall be liable for all damages that occur as a result of the failure to keep the tunnel in repair. Unless authorized by a town meeting, the tunnel shall not be less than 25 feet in length. The electors of the town at an annual town meeting may authorize the construction of a tunnel that is less than 25 feet, but at least 16 feet in length.