Tunneling and Excavation: Using a variety of techniques and equipment, the dense bedrock beneath Manhattan and the mixed face soil under Queens has been excavated and cleared to make room for new train tunnels, platforms, service facilities and ventilation and access shafts. Techniques include tunnel boring, cut-and-cover, drilling and blasting.
Concourse and Terminal Construction: At Grand Central Terminal (GCT), a new passenger concourse is being constructed in space formerly occupied by Metro-North’s Madison Yard. Eight tracks and four passenger platforms are being constructed, along with mezzanines and concourses, beneath Park Avenue below GCT’s existing lower level.
Track Realignment, Reconfiguration and Modernization: Along the length of the ESA alignment, new tracks are being built and old tracks are being replaced. In Harold Interlocking – one of the busiest train interlockings in the United States – work is being done to reconfigure and modernize the complex system of switches and tracks that serve four commuter rail systems and a cargo freight rail with the goal of smoothing and speeding travel through the area. Benefits from this work will impact rail passengers using the northeast corridor.
Power and Ventilation Facilities: At selected locations above and below ground, new facilities for ventilating the tunnels and concourse and powering trains are being constructed. In addition, numerous existing facilities are being modernized and improved.
Storage and Maintenance Facilities: In Queens and the Bronx, new facilities for storing and maintaining trains during the day are being constructed.
(Courtesy of MTA)