Central Tri-State Tollway Mile Long Bridge (I-294) Reconstruction – Cook County, IL

M Squared Engineering, LLC (M²) served as the hydraulic engineer on this urban freeway bridge construction project. The project replaces the existing Mile Long Bridge over the Des Plaines River, Chicago Sanitary and Ship Canal, the I&M Canal, the CN Railroad, and the BSNF Railroad yard. The project also widens the I-294 bridge to increase capacity along the Interstate while maintaining appropriate vertical and horizontal clearances over the railroad and three channels.

Assigned tasks included providing stormwater management, drainage analysis and design, development of a design deviation meeting all Tollway requirements, construction staging/sequencing for the proposed drainage design, railroad coordination support, and stream hydraulic analysis for three streams, including complete hydraulic reports. The stream hydraulic analysis accounted for the complex nature of the existing condition, hydraulic models from both FEMA and MWRD. It included a detailed analysis for temporary conditions required during construction, including cofferdams, causeways, and other temporary works required for construction of the proposed bridge.

In addition, we helped with the complex drainage hydraulics required to evaluate repetitive flooding concerns in adjacent neighborhoods that drain into the project site.

SERVICES

• Complex Drainage Analysis
• River Hydraulics
• Stormwater Management
• Design Support
• Drainage Construction Sequencing & MOT Drainage Design
• FEMA Related Analysis