IL Route 111 is a significant north-south minor arterial route west of Interstate 255 in the Illinois Metro East. Near the interchange with Interstate 55/70, IL Route 111 has a four-lane cross section with dual structures crossing the Cahokia Drainage Canal. When the road was widened to four lanes, a new northbound structure was built, while the southbound structure from 1961 remained in use. This project involved designing a new southbound bridge to replace the old deteriorated structure.

Working with IDOT District 8 Studies & Plans, HMG conducted the Phase I Type, Size & Location (TS&L) bridge design and completed Phase II construction plans. The new structure is a 3-span steel bridge measuring 318 feet from abutment to abutment. Key design challenges included a 61.5° skew angle and managing superelevation transitions on the bridge, which required detailed modeling using Bentley’s Open Bridge Designer—one of the first large skew bridges in the state designed with this software. In addition to the bridge design, HMG designed traffic control, roadway improvements, entrance relocation, and guardrail upgrades. The project was let in March 2024.