St. Clair County, IL Sidewalk & Pedestrian Rules: Obstruction Rules (2026)

Motor Vehicle Code Sec. 24-1-3 defines an encroachment as any building, fence, sign or other structure or object placed, located or maintained in, on, under or over any portion of a project right-of-way, or a roadway right-of-way where no project right-of-way line has been established. The ordinance flatly states it is unlawful for any person, firm or corporation to erect, cause to be erected, retain, or cause to be retained any such encroachment within those limits. The only carve-out is a defined 'Permissible Encroachment': an existing awning, marquee, advertising sign or similar overhanging structure supported from an adjacent building, and only so long as it does not impair the free and safe flow of traffic on the highway.

That exception does not extend to signs hung from freestanding poles set up outside the project right-of-way line. Project right-of-way lines are jointly established by the County Road District, the State, and the Federal Highway Administration on federally funded projects; on other county roads, the ordinance sets the project right-of-way line equal to the roadway right-of-way line, so the ban reaches the full width of the county's road easement, not just the paved surface. The provision traces to Ordinance No. 9, adopted May 29, 1973, and remains in force under the current Motor Vehicle Code codification.

Because it sits in the County Road District's chapter rather than the zoning code, it governs fixed structures placed over the right-of-way itself, distinct from setback rules that govern what a landowner can build on private property near the road.