Wis. Stat. § 87.05
The hearing under s. 87.04 shall be confined to the question whether the improvement prayed for in the petition is required by the public health, safety, convenience or welfare. Any person interested may appear at such hearing in person or by attorney and be heard upon said question without the filing of any formal pleading. In considering and deciding this question the department may consider investigations and reports made by the engineering staff and by the U.S. government or an officer or agency thereof, provided such reports are made a part of the record of the hearing. If at the close of such hearing the department determines that the public health, safety, convenience or welfare require the abatement or substantial diminution of the flood conditions referred to in the petition, it shall make written findings to that effect and shall direct the hearing upon the petition to proceed; but if its finding is to the contrary, it shall enter an order dismissing the petition.
Wis. Stat. § 87.05