65 ILCS 5/11-12-4.1
Whenever a municipality of more than 500,000 population has created a plan commission pursuant to the provisions of this Division 12, every plan, design or other proposal by any public body or agency which requires the acquisition or disposition of real property within the territorial limits of the municipality by any public body or agency, or which changes the use of any real property owned or occupied by any public body or agency or the location of any improvement thereon within the territorial limits of the municipality, shall be referred to the plan commission by such public body or agency not less than 30 days prior to any election for the purpose of authorizing the borrowing of money for, or any action by such public body or agency to appropriate funds for, or to authorize such changes or the acquisition or disposition of such real property, but in no event shall such referral be less than 30 days prior to making such changes or acquiring or disposing of such real property. The plan commission shall review every such plan, design or other proposal and shall within 30 days after submission thereof report to the public body or agency having jurisdiction over such real property or improvement thereon concerning the conformity of the plan, design, or other proposal with the long range planning objectives of the municipality and with the official plan for the municipality or any part thereof if the same shall then be in effect as provided in Section 11-12-2. Such report shall be spread of record in the minutes or record of proceedings of such public body or agency. A report that any such plan, design, or other proposal is not in conformity with the long range planning objectives of the municipality, or the official plan for the municipality shall be accompanied by a written statement of the respects in which such conformity is lacking but such a report shall not bar the public body or agency having jurisdiction over such real property or improvement thereon from thereafter making such changes or acquiring or disposing of such real property. The failure of the plan commission to report on any such plan, design, or other proposal within 30 days after submission of the same to it, shall be deemed to be a report that such plan, design, or other proposal conforms in all respects with the long range planning objectives and the official plan of the municipality.
As used in this section the terms "public body" or "agency" include the State of Illinois, any county, township, district including the Chicago Park District, school, authority, municipality, or any official, board, commission or other political corporation or subdivision of the State of Illinois, now or hereafter created, whether herein specifically mentioned or not.
65 ILCS 5/11-12-4.1