625 ILCS 5/11-605.2

(a) A local agency may delegate to its superintendent of highways the authority to set and post a reduced speed limit for a construction or maintenance zone, as defined in Section 11-605.1, under subsection (c) of that Section. (b) If a superintendent of highways sets a reduced speed limit for a construction or maintenance zone in accordance with this Section, the local agency must maintain a record that indicates: (1) the location of the construction or maintenance zone; (2) the reduced speed limit set and posted for the construction or maintenance zone; and (3) the dates during which the reduced speed limit was in effect.