CHA Consulting, Inc. (CHA) earned a Silver Award at the 2026 ACEC Massachusetts Engineering Excellence Awards for the Maffa Way and Mystic Avenue Bridge Replacement in Boston’s Sullivan Square. The project was recognized for inventive engineering, digitally informed delivery, and constructable solutions within one of Greater Boston’s most constrained transportation environments.
Located in Sullivan Square beneath the I-93 viaduct and spanning seven active rail lines, the Maffa Way and Mystic Avenue bridges no longer met modern structural, safety, or multimodal standards. With virtually no room to raise the roadway, the Massachusetts Department of Transportation (MassDOT) engaged CHA to deliver a durable, low-maintenance solution that balanced safety and constructability while maintaining constant rail and roadway operations below.
CHA designed custom ultra-shallow steel plate girders to meet railroad clearance requirements without altering roadway grades. The design was refined through advanced modeling and precision detailing to support fabrication and staged construction, enabling the reuse of existing substructures and avoiding costly foundation reconstruction. Accelerated bridge construction techniques, paired with carefully orchestrated rail shutdowns, allowed the work to proceed while maintaining vehicular, pedestrian, and transit access through the corridor.
Completed on schedule and within budget, the $39.2 million project improves safety and mobility with widened, ADA-compliant sidewalks, dedicated bicycle accommodations, and enhanced transit operations. The replacement bridges support MassDOT’s Complete Streets and Vision Zero goals and demonstrate CHA’s ability to apply innovative design and digital coordination to deliver high-value infrastructure solutions in dense urban settings.
CHA team members accepted the award at the ACEC Massachusetts Engineering Excellence and Awards Gala on April 14, 2026, in Boston. The project will also receive a National Recognition Award at the ACEC National Engineering Excellence Awards Gala in Washington, D.C.
The American Council of Engineering Companies of Massachusetts (ACEC/MA) represents over 120 engineering, architectural, and land surveying firms committed to advancing the state’s infrastructure. Its annual awards program celebrates projects that exemplify innovation, complexity, and societal impact. Learn more at ACEC/MA’s official website.