65 ILCS 5/11-91.2-1

A county or the State may surrender its jurisdiction over the right-of-way and improvements of all or part of a county or State highway, street or road to a municipality by agreement made between the corporate authorities of the municipality and the county board or the Illinois Department of Transportation, as the case may be. The agreement shall provide that the right-of-way and improvements continue to be used as a road, street or highway and that the municipality be chargeable with the repair, maintenance and upkeep of the right-of-way and improvements. The municipality may exercise its police powers over the right-of-way and improvements in like manner as if the right-of-way and improvements lay entirely within the municipality.