Major structural replacement work on the Metropolitan Transportation Authority’s (MTA) Park Avenue Viaduct has been completed five years ahead of schedule and $195 million under budget. Since October 2023, the MTA reports that crews have replaced 196 bridge structures and more than 12,600 feet of railroad over 28 weekends without delaying a single train. The $765 million project fortifies the long-term reliability and resiliency of the corridor that carries 98% of all Metro-North Railroad service and all trains traveling into and out of Grand Central Terminal.

“This is what it looks like when government delivers: a major project to modernize essential infrastructure completed years ahead of schedule and hundreds of millions of dollars under budget, all without impacting service,” said New York Gov. Kathy Hochul. “The Park Avenue Viaduct is critical, and by replacing infrastructure dating back to the Gilded Age, hundreds of thousands of Metro-North riders will now benefit from a smoother and more reliable ride.”

The 133-year-old Park Avenue Viaduct carries four Metro-North tracks above Park Avenue from the Park Avenue Tunnel at East 97th Street to the Harlem River, supporting approximately 750 trains and 260,000 passengers each day through one of New York City’s most constrained rail corridors. With nearly half of the viaduct’s girders dating to the 1890s, the MTA launched the project to reconstruct critical portions of the 1.8-mile structure between East 110th Street and the Harlem River Lift Bridge, including the replacement of aging sections between East 115th Street and East 132nd Street while maintaining full Metro-North service.

“This project is the gold standard for major infrastructure work—modernize what matters most, without making riders suffer through disrupted service,” said MTA Chair and CEO Janno Lieber. “The Park Avenue Viaduct may not be glamorous, but its continued deterioration was a real threat to the entire Metro-North system.”

Metro-North also received the American Public Transportation Association’s 2026 Gold Award for Safety for the project for the innovative work that allowed for the replacement while maintaining service.

“The Park Avenue Viaduct replacement is proof that modernization doesn’t have to come at the expense of great service,” said MTA Construction and Development President Jamie Torres-Springer. “Using creative design and construction innovations, this project is a hallmark example of how the MTA is delivering major upgrades across the system better, faster, and cheaper—and all while keeping New Yorkers moving.”

The structural replacement was completed in two phases. Phase 1, spanning East 115th Street to East 123rd Street, began in October 2023 and was completed 21 months ahead of schedule in October 2025. Phase 2, spanning East 127th Street to East 132nd Street, began in May 2024, with the final viaduct replacement completed during the weekend of July 25—60 months ahead of schedule. With the replacement of the structure complete, the MTA says the remaining work, including track replacement, cable installation and the removal of temporary fencing and girders, is expected to be completed by September 2027.

“This project touches nearly every Metro-North customer and completing structural work of this scale without delaying a single train is an extraordinary achievement,” said MTA Metro-North Railroad President Justin Vonashek. “The modernized viaduct will remain a central artery of Metro-North’s operations, supporting safe, reliable service to and from Grand Central Terminal for decades to come.”

Project innovations deliver work better, faster and cheaper

To maintain regularly scheduled train service and accelerate construction, the MTA used multiple custom-designed gantry systems to lift and place prefabricated bridge units weighing nearly 190,000 pounds each. Unlike traditional crane operations, the gantries allowed crews to install the units during tightly coordinated weekend work windows without delaying service.

The MTA also reports that the project used an intertrack containment system to create enclosed work zones between active tracks, allowing construction to proceed while trains continued operating on adjacent tracks. The agency notes that the approach reduced the need for flagging personnel, lowering project costs and providing a model for performing major construction in other narrow, active rail corridors.

Bridge components were prefabricated and assembled off-site, reducing the amount of work performed on the viaduct, limiting workers’ exposure to a high-risk environment and creating more predictable weekend schedules. This allowed replacements to take place over 48-hour weekend work windows.

Modernizing the Grand Central Artery

The MTA says that as ridership and demand grow, major structures serving Metro-North riders—including the Grand Central Terminal train shed, Park Avenue Tunnel and Park Avenue Viaduct—are more than 100 years old and in need of replacement. Together, these three structures make up the Grand Central Artery. To provide safer and more reliable service for generations to come, the MTA says it is making major investments to modernize this infrastructure. Between updates along Park Avenue and the replacement of the Grand Central Terminal train shed, the MTA notes it is making $2.9 billion in capital investments to improve Metro-North service for generations to come.