315 ILCS 30/4

The governing body of any municipality having more than 500,000 inhabitants, as determined by the last preceding Federal census, and in which there exist both a land clearance commission and a conservation board, by ordinance adopted by a majority of its members, may determine that there is need to consolidate the functions of the land clearance commission and of the conservation board in a single body and provide for the creation of a Department of Urban Renewal to operate within the boundaries of such municipality pursuant to the provisions of this Act.