The Massachusetts Bay Transportation Authority has awarded one of the largest commuter rail infrastructure contracts in American history — a $1.06 billion design-build agreement to replace the nearly 100-year-old Draw One rail bridges across the Charles River at Boston's North Station. Skanska announced the award on May 6, 2026, with construction beginning that same month. The project is scheduled for completion in Fall 2032.

What Happened

The MBTA selected a joint venture led by Skanska USA Civil to deliver the North Station Draw One Bridge Replacement and Associated Track and Signal Upgrades project — a design-build contract covering Cambridge, Boston, and Somerville. VHB, an engineering and planning firm headquartered in Watertown, Massachusetts, is the design partner. Work began in May 2026 with an expected completion in Fall 2032.

The existing bascule bridges were built in 1931 and were the first moving railroad drawbridges constructed in the United States. Originally part of a four-bridge crossing, two spans remain in service today. They carry four commuter rail tracks serving the Haverhill, Lowell, Newburyport/Rockport, and Fitchburg lines — routes that collectively move more than 11 million riders annually across MBTA Commuter Rail and Amtrak. The bridges also include a control tower managing roughly 200 daily train trips and must accommodate river traffic beneath.

Key Project Details

• Contract value: $1.06 billion (design-build)
• Owner: Massachusetts Bay Transportation Authority (MBTA)
• Construction manager: Skanska USA Civil (JV with Koch)
• Design partner: VHB, Watertown, MA
• Federal funding: $472 million awarded in September 2024 by the U.S. Department of Transportation
• Scope: Replace two 1931 bascule bridges with three new vertical lift spans; upgrade 1.5 miles of track; construct new Tower A control facility; add Platform F at North Station; expand crossing from four to six tracks; comprehensive track, signal, and Positive Train Control upgrades
• Annual ridership served: More than 11 million (commuter rail and Amtrak)
• Timeline: Construction start May 2026; scheduled completion Fall 2032
• Design life: Expected to last 75 to 100 years

The new structure will replace the two original drawbridges with three vertical-lift spans, expanding capacity from four tracks to six across the river. The additional tracks connect directly to tracks 11 and 12 inside North Station, completing a platform that has been in an unfinished state for decades. The project team will also implement what Skanska calls Alternative Technical Concepts — engineering innovations designed to reduce in-water work, simplify construction staging, and improve safety while keeping trains running throughout the multi-year build.

Why It Matters to Construction Professionals

Rail bridge replacements of this complexity — a working movable structure over a navigable waterway, adjacent to a major urban terminal handling 200 daily train movements, surrounded by 13 identified physical constraints including Massachusetts General Hospital, Boston Sand and Gravel, and the Zakim Bridge overhead — demand an exceptionally high level of construction coordination. Construction crews will use portions of a parking lot near a Massachusetts General Hospital administrative building on the downtown side of the river, underscoring the tight site conditions.

The decision to maintain uninterrupted commuter rail and Amtrak service throughout the six-year construction window — with weekend service accommodated through existing subway and bus systems during the most disruptive work phases — is a defining constraint that shapes the entire construction sequence. Phased track transitions, temporary staging over water, and continuous coordination with MBTA operations will characterize this project from start to finish.

The federal funding component — $472 million from the U.S. Department of Transportation, awarded in September 2024 — reflects the Biden-era Infrastructure Investment and Jobs Act's emphasis on rail and bridge modernization. That grant covers roughly 45 percent of the total project cost, with the remainder funded through MBTA capital resources.

Implications for Owners, Developers, and Contractors

For heavy civil and specialty marine contractors, the Draw One project represents the kind of technically demanding, long-duration work that builds firm backlogs and deepens specialized capabilities. Skanska's use of VHB as design partner — a firm with deep New England transit and infrastructure experience — positions the team to navigate the local regulatory environment effectively.

The project is also significant for the broader Boston-area construction market, arriving at a time when the region is managing multiple concurrent large-scale infrastructure programs. Contractors and subcontractors positioned in underwater construction, rail systems integration, structural steel fabrication, and Positive Train Control installation should expect active recruitment as the project ramps up.

For transit agencies and infrastructure owners nationwide, this project is a case study in how aging movable bridges — a category representing hundreds of structurally deficient spans across the country — can be replaced while maintaining operations. The design-build delivery model, federal grant funding, and long-term design life expectations are increasingly standard elements of major bridge replacement programs.

What to Watch Next

• Early subcontractor procurement announcements from Skanska/Koch JV
• First scheduled weekend service disruptions and MBTA mitigation plans
• Progress on signal and PTC upgrade work, which a separate $61 million contract has been advancing since July 2025
• Milestone completion of the first new vertical-lift span, expected mid-program
• Broader MBTA capital program activity — the authority has several concurrent infrastructure investments underway across its system

Bottom Line

The $1.06 billion MBTA North Station Draw One Bridge replacement is one of the most technically demanding rail infrastructure projects active in the United States today. Replacing 1931 bascule bridges while maintaining service for 11 million annual riders — with six years of phased construction over a navigable urban waterway — defines the complexity at the leading edge of U.S. transit modernization. For construction professionals specializing in heavy civil, marine, and rail systems work, this project sets a clear benchmark for what large-scale transit infrastructure delivery looks like in 2026.

Sources

• Skanska USA – Official Press Release (May 6, 2026)
• Boston Globe – Drawbridge Replacement at Boston's North Station to Start in May (May 10, 2026)
• Wikipedia – Charles River Bridge (Commuter Rail) – Historical and Technical Background
• Equipment World – Skanska to Replace Historic Boston Rail Bridges (May 14, 2026)