65 ILCS 5/11-141-10.5
The corporate authorities of any municipality shall not restrain or interfere with an adjacent municipality's construction, maintenance, alteration, or extension of a sewerage system that accesses intercepting and outlet sewers of a third consenting wastewater treatment authority outside of the adjacent municipality's corporate boundaries provided that the construction, maintenance, alteration, or extension is an appropriate or practical route, according to any Environmental Protection Agency engineer, and is necessary to maintain or establish compliance with the Environmental Protection Act or rules or regulations promulgated by the Pollution Control Board.
Any municipality granting access to intercepting and outlet sewers of a third consenting wastewater treatment authority may recover only its actual costs, including but not limited to inspection, regulation, administration, and repair costs, associated with any construction, maintenance, extension, or alteration of the existing system.
65 ILCS 5/11-141-10.5