I-270 North Design-Build

Photo Credit: Millstone Weber, LLC

The I-270 North Design-Build Project exemplifies the successful application of design-build to meet complex transportation challenges. Located in St. Louis, Missouri, I-270 is a critical corridor, carrying over 140,000 vehicles daily, including a significant percentage of heavy truck traffic. Initially built in the 1960s, the corridor had long been plagued by aging infrastructure, severe congestion and safety issues. The Missouri Department of Transportation (MoDOT) recognized that a design-build approach would be essential to address these challenges effectively, leveraging industry expertise and innovation.

A Major Milestone in Missouri’s Infrastructure Evolution

The project focused on reconstructing and rehabilitating deteriorated pavements, repairing or replacing structurally deficient bridges, and enhancing traffic operations and safety throughout the corridor. One of the key innovations was the implementation of a Metro Bus-only lane, which directly connected the North County Transfer Center to local destinations, reducing transit route lengths by 300 miles per day and saving significant operational costs. Additionally, MoDOT utilized advanced Traffic System Management and Operations (TSMO) tools, such as dynamic message systems and real-time traffic apps, to improve traffic flow and safety.

The project was completed on time and within budget despite the complexities, including managing traffic while keeping all lanes open during peak times. The success of the I-270 North project was further amplified by its impact on the local community, providing jobs, skills training and long-term economic benefits. The project also enhanced connectivity for pedestrians and cyclists, adding 10 miles of shared-use paths and sidewalks on all structures crossing I-270.

The I-270 North Design-Build Project demonstrates how innovative solutions and strong partnerships can deliver transformative infrastructure improvements and set new standards for regional projects.

Winner – Meaningful DEI Practices

The design-build contractor, Millstone Webber, exceeded underutilized business enterprise (UBE) requirements, achieving 23% minority and 15% female workforce participation – nearly doubling set goals – and surpassed the UBE requirement of 18% construction and 22% professional service participation. They built relationships with local trade unions, pre-apprenticeship and training programs, and government agencies through mixers and job fairs. In addition, their Project PAVE STEM Initiative mentored disadvantaged youth into civil design and construction careers, engaging over 100 high school students with 60 completing the program. One juror noted, “The sustainability of this project is about evolving UBEs, not just meeting a goal.”

Design-Build Team

Photos