Illinois Route 159

Illinois Route 159 is a north–south state highway in southwestern Illinois connecting suburban and rural communities between Scott Air Force Base, Fairview Heights, Belleville, and Hamel. The route serves as a regional arterial linking federal facilities, county seats, commercial districts, and interstates including Interstate 55, Interstate 64, and Interstate 270. It provides access to landmarks and institutions such as Gateway International Raceway, Southern Illinois University Edwardsville, Belleville Township High School, and St. Clair County government centers.

Route description

The corridor begins near Scott Air Force Base and proceeds north through Shiloh and O'Fallon adjacent to military, industrial, and residential zones, intersecting regional routes that link to Lambert–St. Louis International Airport via Illinois Route 203 and to St. Louis, Missouri via the McKinley Bridge and Poplar Street Bridge. Continuing into Fairview Heights, the highway traverses commercial strips next to shopping centers, medical campuses like Gateway Regional Medical Center, and civic nodes tied to St. Clair County Courthouse operations. In Belleville the road passes near historic districts associated with Belleville Public Library and Belleville High School-West, connecting to state routes that serve Madison County agricultural corridors and rail junctions linked to Union Pacific Railroad and Norfolk Southern Railway. Northward through Swansea and Edwardsville suburbs, the alignment provides commuter access to campuses such as Southern Illinois University Edwardsville and cultural sites like N.O. Nelson Campus. Approaching Hamel the highway transitions to rural two-lane sections bordering Montgomery County farmland, intersecting county roads that serve historic villages tied to Illinois Central Railroad routes.

History

Originally designated in the early 20th century during statewide reorganizations led by the Illinois State Highway Commission and contemporaneous with federal initiatives like the Federal Aid Highway Act, the corridor evolved as regional growth around Scott Air Force Base and metropolitan expansion from St. Louis drove incremental extensions and realignments. Mid-century projects associated with interstate construction—namely Interstate 55 and Interstate 64—prompted interchange modifications influenced by planners from Illinois Department of Transportation and consultants tied to firms that worked on St. Louis Gateway Arch National Park area traffic studies. Urban renewal and suburbanization during the postwar era led to commercial corridor development in Fairview Heights and Belleville, attracting retail chains and regional healthcare providers connected to networks such as Ascension Health and academic affiliations with Southern Illinois University. More recent history includes pavement rehabilitation programs following standards set by the American Association of State Highway and Transportation Officials and corridor safety projects coordinated with National Highway Traffic Safety Administration initiatives.

Major intersections

The route intersects multiple arterial and interstate facilities that support regional mobility and freight movement: - Southern terminus near Scott Air Force Base with connections to military access roads and local arteries serving Mascoutah and Columbia. - Interchange with Interstate 64 near Fairview Heights providing east–west linkage toward Mount Vernon and Evansville via I‑64. - Junctions with state routes connecting to Interstate 55 toward Springfield and Chicago corridors. - Crossings near Belleville that interface with U.S. routes serving Alton and Carbondale freight routes tied to Amtrak corridors. - Northern approach to Hamel tying into local county roads that link to Interstate 270 and regional connectors toward St. Charles and Granite City.

Route maintenance and improvements

Maintenance is managed in coordination with the Illinois Department of Transportation and local agencies in St. Clair County and neighboring counties, following standards promulgated by the American Association of State Highway and Transportation Officials. Projects have included resurfacing contracts awarded through competitive bidding processes compliant with state procurement statutes and environmental review frameworks influenced by National Environmental Policy Act guidelines when federal funds or permits were involved. Improvement programs have targeted intersection upgrades, signal timing coordinated with regional traffic management centers that cooperate with Metropolitan Planning Organization, St. Louis partners, and multimodal enhancements to support bus services operated by agencies linked to St. Clair County Transit District and regional planning efforts by the East-West Gateway Council of Governments.

Traffic and usage statistics

Traffic volumes vary from high-density urban segments near Fairview Heights and Belleville—where average daily traffic counts reflect commuter flows to military and healthcare employment centers—to lower counts in rural stretches approaching Hamel. Peak hour patterns correlate with shift changes at Scott Air Force Base and university schedules at Southern Illinois University Edwardsville, and freight peaks align with rail-served industrial zones connected to BNSF Railway. Safety data and crash statistics compiled by the Illinois Department of Transportation inform targeted countermeasures and funding prioritization through state transportation improvement programs administered in concert with federal grants overseen by the United States Department of Transportation.

Category:State highways in Illinois