Crews hoisted 190,000-pound bridge sections in East Harlem and attached them to the newly installed support structure underneath.
They then quickly connected the track and other systems into the rest of the viaduct spanning Park Avenue. The effort marked the completion of the first phase of the $590 million superstructure, early and cheaper than originally planned.
“Today’s milestone demonstrates the transformative work we can get done in New York when we invest in transit,” said New York Gov. Kathy Hochul in a news release. “Completing work on an elevated structure that dates back to the Gilded Age ahead of schedule and under budget shows what’s possible when we modernize our infrastructure and put riders first.”
The work formed part of the Metropolitan Transportation Authority’s overhaul of the 132-year-old Park Avenue Viaduct, over which New York’s Metro North trains have rumbled for decades. The bridge replacement marks the completion of the superstructure for phase 1 of the project, 51 months ahead of schedule and $93 million under budget, according to an Oct. 6 release.
Halmar International, the project’s design-build contractor, replaced 8,240 feet of aging track through 128 bridge installations, all while maintaining the Metro-North service in operation. Using a custom-built gantry system that spanned Park Avenue, crews swapped out prefabricated bridge sections over 19 weekends starting June 2024. The method allowed workers to lift out deteriorated steel and concrete deck segments and install new sections without shutting down service on the other side of the structure.
That approach emerged during the design-build procurement phase between the MTA and the Nanuet, New York-based general contractor, according to the release. By allowing the contractor to propose construction techniques, the project eliminated the need for longer-term shutdowns and accelerated multiple phases simultaneously. Phase 2, which stretches from East 127th Street to East 132nd Street, began in May 2024.
The $590 million first phase, of which $500.9 million stemmed from federal funds, replaced the viaduct’s full substructure and superstructure between East 115th and East 123rd streets and installed new track, power, communications and signal systems, according to the release.
The elevated structure carries four Metro-North tracks and 98% of the railroad’s trains each day. The viaduct connects commuters from the Bronx, Westchester, Putnam and Dutchess counties, as well as Connecticut, to Grand Central Terminal. The project forms part of the Grand Central Artery, which also includes the terminal's train shed and the Park Avenue Tunnel, all more than 100 years old.
While the entire structure for phase 1 is now complete, additional work on the systems and track level will continue through the winter, according to the release. MTA expects phase 1 to reach substantial completion in April 2026, and phase 2 to finish in September 2027.
