The Arthur J. DiTommaso Memorial Bridge in Fitchburg, Massachusetts, is a landmark twin‑tower cable‑stayed structure spanning the North Nashua River and active railroad tracks. As only the second bridge of its type constructed in Massachusetts, it provides a modern, visually striking and structurally efficient replacement for a deteriorated 1912 reinforced concrete arch bridge that had been closed for decades. STV served as the design engineer, leading the evaluation, bridge‑type study and full structural design that resulted in the selection of a cable‑stayed solution suited to the site’s complex constraints.
What challenges did STV address?
The original six‑span 1912 arch bridge had deteriorated beyond repair, prompting a detailed inspection and feasibility review. Challenging soil conditions, limited clearances, restrictive roadway grades and the presence of the North Nashua River required a bridge type that provided long spans, minimized foundation impacts and improved geometric conditions. The structure also needed to safely cross both water and rail lines while enhancing the corridor’s long‑term reliability.
What solutions did STV deliver?
STV conducted a bridge‑type study that led to the adoption of a cable‑stayed design. The new 660‑foot bridge includes a 356‑foot main span supported by 52 cables connected to two 275‑foot reinforced concrete towers. STV delivered complete structural and civil engineering design and documented the historic 1912 arch bridge for the Historic American Engineering Record (HAER) prior to its demolition.
How does this project benefit the community?
The new bridge restores a critical crossing, provides safer and more efficient travel and enhances Fitchburg’s infrastructure with a resilient, low‑maintenance structure. Its graceful profile also contributes to community identity while supporting long‑term mobility.
Key stats and accolades
- 660‑foot cable‑stayed bridge with 356‑foot main span
- Two 275‑foot reinforced concrete towers
- 52 stay cables supporting the superstructure
- HAER documentation performed for the historic 1912 arch bridge
