The massive East Side Access project in New York City reached a milestone on Jan. 29 as crews completed excavation. The final bit of excavations was completed by drill-blast as part of a ventilation structure on the northern end of the cavern on the Manhattan side.
The East Side Access project for MTA Capital Construction will connect the Long Island Rail Road’s (LIRR) Main and Port Washington lines in Queens to a new terminal beneath Grand Central Terminal in Manhattan. The new connection will increase the LIRR’s capacity into Manhattan, and dramatically shorten travel time for Long Island and eastern Queens commuters traveling to the east side of Manhattan. Currently, LIRR service into Manhattan enters through Penn Station on the West Side where it terminates.
The project consists of excavating tunnels approximately 140 ft beneath Manhattan streets with two TBMs (one by SELI and one Robbins TBM). The TBMs in Manhattan made eight successful tunnel drives starting and ending at various points along the alignment. At the end of November 2009 all of the upper tunnel drives were completed and in 2011, all the Manhattan tunnels were successfully mined.
Following tunnel boring operations, excavation of the caverns under Grand Central Terminal that are to become platforms and a mezzanine for the new trains began. Concurrently, four soft-ground TBM tunnels were constructed in Queens using two slurry TBMs. These tunnels will connect trains to the new tunnels and under existing traffic in Sunnyside Yard. Additionally, the short Northern Boulevard Crossing was completed using the soil freezing technique of excavation The crossing will eventually connect existing traffic in the Sunnyside Yard/Harold Interlocking area to new tunnels in Manhattan. TBM boring totaled more than 22,900 lf on the Manhattan side and 10,600 lf on the Queens side, all 20-plus ft. in diameter.
While excavation is complete, much work remains. Crews are currently waterproofing and concreting caverns, which will be followed by systems installations, including track work, electrical, ventilation, lighting, mechanical, etc.
East Side Access is the largest project ever undertaken by the MTA and at a cost of more than $9 billion is one of the largest infrastructure projects currently under way in the United States. Project completion is currently under review.