RR-14-4221 Tri-State Mile Long Bridge Project – I-294

The Mile Long Bridge project replaces the existing I-294 bridge over the Des Plaines River, the Chicago Sanitary and Ship Canal, the I&M Canal, and active CN and BNSF railroad yards. The project also widens the bridge to increase interstate capacity while maintaining required vertical and horizontal clearances over waterways, railroads, and surrounding infrastructure. The improvements enhance traffic flow, safety, and long-term resilience of one of Cook County’s most critical transportation corridors.g

Engineering for Hydraulic Reliability
DB Sterlin provided comprehensive hydraulic engineering services for the project, including hydraulic modeling using HEC-RAS, XPSWMM, SSA, and TR-20, stormwater management design, temporary drainage layouts, and construction sequencing for drainage elements. The team developed hydraulic reports and design deviations to meet all Tollway requirements, ensuring the bridge’s substructure and surrounding waterways remain resilient during construction and long-term operation.

Navigating Infrastructure Complexity
The project required close coordination with railroad operators, regulatory agencies, and stakeholders to manage construction over multiple waterways and active rail yards. DB Sterlin’s team designed temporary construction measures, including cofferdams and causeways, while maintaining traffic flow, controlling stormwater, and mitigating flooding impacts on adjacent neighborhoods.

Building for the Future
Through advanced hydraulic modeling, detailed stream analyses, and innovative drainage solutions, DB Sterlin supported a safe, reliable, and resilient infrastructure upgrade that improves interstate mobility and flood management.