Massachusetts Department of Transportation Interstate I-90 Multiple Bridge Replacements

Massachusetts Department of Transportation (MassDOT) initiated a project to replace five bridges, rehabilitate one, and replace the superstructure of two. The project aimed to enhance safety, raise vertical clearance, improve seismic resilience, and minimize noise impact. Additionally, it included such tasks as constructing retaining walls, removing toll plazas for electronic tolling, and addressing various environmental, survey, hydraulic analysis, and traffic management challenges.

GPI is responsible for engineering design and the foundational technical concept, as well as developing design-build procurement documents for replacing various structures along I-90. A key focus is the structure carrying I-90 over I-95 and the Charles River. The design aims to replace existing bridges, improving vertical clearance and safety without compromising vehicle capacity – an essential consideration for this crucial roadway noted for congestion. The construction process requires uninterrupted critical utilities, including fiber optics and significant water supply lines. For the bridge over the Massachusetts Bay Transportation Authority (MBTA) railroad on I-90, accelerated replacement techniques were employed due to the unfeasibility of phased construction for both the roadway and railroad operations. GPI collaborated with the MBTA to identify approved work windows, coordinate weekend shutdowns, move utilities, and integrate MBTA and American Railway Engineering and Maintenance-of-Way Association (AREMA) requirements into the plans and specifications.