Ill. Admin. Code tit. 92 § 544.40
For purposes of this Part:
"Department" means the Department of Transportation, and "State" means the State of Illinois.
"Energy Charges" include the costs of supplying electrical energy for the operation of the signals.
"Installation" includes the costs involved in the preparation of plans and performing construction inspection, as well as the construction costs of installing the traffic signals at an intersection.
"Intersection Approaches" include both legs of one-way streets as if they were carrying two-way traffic.
"Local Agency" refers to county, township, or municipal governments.
"Maintenance" includes costs of routine maintenance on the signals, as well as emergency repairs in the event of malfunction of the controller or physical damage resulting from accidents, severe weather, or vandalism.
"Modernization" includes all engineering costs, as well as the construction costs of altering or modifying an existing signal installation, either to bring it into conformance with the current Illinois Manual on Uniform Traffic Control Devices (92 Ill. Adm. Code 546), to satisfy a need for improvement in the operation of the signals, or to correct an accident problem at an intersection. The modernization may include altering the operation through changes in sequencing and timing or modification of the physical layout of the signals.
"State Highway" refers to any highway, regardless of whether or not it is a marked route, that is maintained by State forces or maintained by others, with total or partial reimbusement by the State.
Ill. Admin. Code tit. 92, § 544.40