70 ILCS 1310/3

The location, design, construction, maintenance and control of any improvement made under the provisions of this Act, shall be and remain in the board of park commissioners, any agreement, rule, regulation, ordinance or statute to the contrary notwithstanding. The board of park commissioners is authorized and empowered to make and enforce rules and regulations for the use, care, control and maintenance of any improvement made under the provisions of this Act and is authorized and empowered, where the public good will not be impaired, to enter into agreements and contracts concerning the leasing of such portions of the substructure, structure or superstructure, as may not at the time be used for public purposes.