430 ILCS 105/1

(This Act was repealed by P.A. 89-7, which has been held unconstitutional)

All construction work upon bridges or highways within the State of Illinois shall be so performed and conducted that two-way traffic will be maintained when such is safe and practical, and when not safe and practical, or when any portion of the highway is obstructed, one-way traffic shall be maintained, unless the authorized agency in charge of said construction directs the road be closed to all traffic.