The Metropolitan Transportation Authority’s (MTA) East Side Access project is the largest transportation infrastructure project implemented in North America and involved the expansion of the Long Island Rail Road (LIRR), the busiest commuter railroad in the US.

It provides an alternative new stop for all the 11 LIRR branches at a new terminal and concourse beneath Grand Central Terminal (GCT) and includes 11 miles (17.7km) of tunnelling works at Queens Borough and Manhattan. The project increases the LIRR’s train services in Manhattan by approximately 45% and shortens the travel time for approximately 162,000 commuters travelling from Long Island and eastern Queens to the east side of Manhattan by approximately 40min a day. It also eases congestion on the city’s trains and subways, especially in the neighboring Pennsylvania Station.

Mined caverns, each with an upper and lower level, separated by a mezzanine level, were constructed under the existing lower level of the GCT to create a new 300,000 sq. ft. passenger concourse where eight tracks and four passenger platforms are provided. The LIRR’s Harold Interlocking, the busiest passenger train interlocking in the US, was also reconfigured.

Elevators, escalators and emergency egress stairs were installed to provide connections from the new terminal to the GCT”s dining concourse and the old arrivals waiting room, along with connections to the 45th Street and 47th Street cross- passages. New tracks were built and old tracks replaced along the alignment of the East Side Access, while train storage and maintenance facilities were constructed at Queens and the Bronx. Ventilation buildings were also built at 38th, 44th, 50th and 55th Streets. Other infrastructure included power stations, new entrances, exit shafts and ancillary surface works for the tunnels and concourse.

PACO Group, as the largest subconsultant on the project, provided key program management services that included field engineering, inspection, CPM scheduling, cost control, real estate acquisition/right of way, risk analysis, document control, value engineering, administrative/graphics support, partnering, and contract administration.