Wis. Stat. § 195.042: Summary investigations.

Whenever the office believes that any water carrier rate or charge may be unreasonable or unjustly discriminatory or that any service is inadequate or cannot be obtained or that an investigation of any matter relating to any water carrier or, if a matter arising under s. 192.324, 192.34, 195.20, 195.28 (1), 195.285 (1), 195.29 (1), (5), or (6), 195.31, or 195.32, to any railroad should for any reason be made, it may investigate the same with or without notice.