Case Study: Owner’s Late Design Changes on Bridge Project in Illinois (2020)

Project Overview
• Name: I-74 Mississippi River Bridge Replacement
• Location: Moline, Illinois to Bettendorf, Iowa
• Year: 2020
• Project Size: $1.2 billion
• Scope: Dual-structure cable-stayed bridge with interchanges and pedestrian/bike facilities
• Lead Agencies/Contractors: Illinois DOT, Iowa DOT /

Category of the Issue, Problem, or Challenge
• Contract Owner
• Design Management

Summary of the Issue, Problem, or Challenge
During superstructure work, the owner issued a major design change to accommodate future rail expansion—well after structural steel had been procured. The change required new connection details and longer lead-time fabrication.

Root Cause Analysis

• Design revisions were driven by late-stage interagency agreements.
• Coordination gaps existed between owner planning and active construction.
• The impact of changes on schedule and procurement was underestimated.

Impacts Due to the Issue, Problem, or Challenge

• Steel deliveries delayed by 4 months due to redesign and re-fabrication.
• Temporary work stoppages and rework impacted bridge segmental assembly.
• Claims totaling $11.7 million were filed for delay and remobilization.

Corrective Actions Taken

1. Interagency coordination timelines were restructured to front-load all scope impacts.
2. Late-stage design changes now trigger formal constructability reviews.
3. Future large bridge projects require locking design prior to procurement milestones.

Lessons Learned

• Design lock-in must precede material procurement on megaprojects.
• Owner planning must align with downstream construction impacts.
• Interagency MOUs can create design ripple effects if not timed correctly.

Audit & Prevention: Project Control Questions to Ask on Future Projects to Help Control the Situation

• Have all external stakeholder design needs been finalized before bid?
• Is there a formal process for evaluating the construction impact of late design changes?
• Are material procurement triggers aligned with design freeze milestones?