STV’s design team that rehabilitated an over 175-year-old bridge in Massachusetts was recognized with the Bronze Award from the American Council of Engineering Companies of Massachusetts (ACEC/MA).
The Massachusetts Department of Transportation (MassDOT) Rail and Transit Division has been steadily restoring its freight and passenger rail lines along the Connecticut River Mainline (CRML) corridor that courses throughout the state. Historically used for freight rail, the CRML Bridge 47.90, located in Northfield, MA, is now seeing increased passenger service along its tracks.
STV served as engineer-of-record for the project, providing preliminary and final design services as well as bridge inspection and construction oversight. During its inspection, the team found that water was collecting along various sections of the bridge’s masonry stone arch structure, which would freeze in the winter and cause cracks and fissures.
Originally constructed in 1848, the bridge can only be closed for one, 72-hour construction window each year. STV developed a rehabilitated design over three months that accommodated the project’s accelerated construction schedule, while also implementing long-term solutions for the bridge.
“This was a successful project that we were able to utilize accelerated bridge construction techniques, implement modern safety features and reopen the bridge ahead of schedule on a rapidly aging yet vital connection for MassDOT’s rail corridor,” said Michael Scott, PE, senior associate and project manager for the CRML Bridge 47.90.
Scott accepted the ACEC/MA award alongside colleagues William Goulet, P.E., S.E., a senior structural engineer at STV, and Marian Barth, PE, vice president and area manager for the Boston region. The team also celebrated STV’s Alison Love, SE, PE, who earned ACEC/MA’s 2024 Young Professional Award.
“We identified that a full bridge replacement would set the project back significantly in terms of cost and schedule, while the rehabilitation option would allow for shorter construction time, lower construction costs and provide an additional 75-year service life for the bridge,” Michael said.
After MassDOT selected the rehabilitation option, STV designed a precast concrete deck panel system to fit the expedited construction schedule, as well as a waterproofing and drainage system, and repairs to the cracked sections of the bridge. Rapid setting concrete was used for closure pours between the precast panels, while a spray-applied waterproofing system, drainage gates and drainpipes are redirecting water away from the structure.
Over the past year, the rehabilitated structure has carried four passenger trains as part of a MassDOT pilot program.
“The project is a true example of how to rehabilitate existing infrastructure using accelerated methods—even on structures that are close to 200 years old,” Barth said. “We’re really proud of the project team for developing a long-term solution that will benefit MassDOT and its passengers as it continues to expand its service.”
