Wis. Stat. § 38.18: Contracts and bidding.

All contracts made by a district board for public construction in a district shall be let by the district board to the lowest responsible bidder in accordance with s. 62.15 (1) to (11) and (14). For purposes of this section, the district board shall possess the powers conferred by s. 62.15 on the board of public works and the common council. All contracts made under this section shall be made in the name of the district and shall be executed by the district board chairperson and district board secretary.