70 ILCS 3405/1
It is declared as a matter of legislative determination that in order to promote and protect the health, safety, welfare and convenience of the public, it is necessary in the public interest to provide for the creation of municipal corporations known as surface water protection districts and to confer upon and vest in the surface water protection districts all powers necessary or appropriate in order that they may engage in the acquisition, establishment, maintenance and operation of ditches, channels, flumes or similar waterways, trunk sewers, lateral sewers, manholes, street inlets, roadway culverts, outlet structures, junction chambers, pumping stations, retention basins, dams, levees, gate structures, spillways, control works, or any other types of construction necessary for the collection of surface waters within the district boundaries, and the subsequent conveyance and disposal of such waters at suitable points of discharge, and provide as nearly adequate protection from property loss and damage to lives and property within the district as possible; and that the powers herein conferred upon such surface water protection districts are public objects and governmental functions in the public interest.
70 ILCS 3405/1