Second Avenue Subway

TBM, cut-and-cover and mining techniques used

Much of the two-track line was built using tunnel boring technology with cut-and-cover used at the 96th Street station locations. Mining was used on two station caverns at 86th and 72nd streets and portions that were too short to make tunnel boring cost-effective. The geology of the Upper East Side of Manhattan posed challenges for the team because of its hills and valleys; Manhattan schist, a mixture of unpredictable and variable sands and silts; and fault lines. In addition, the existing 63rd Street/Lexington Ave station was renovated to allow the new Second Avenue Subway to tie into the existing transit system.

Location

New York, USA

Client

New York Metropolitan Transportation Authority

Project status

Opened January 1, 2017

Miles of Tunnel

1.5

New Stations

3

Passengers Served Daily

200,000

Addressing community concerns

During construction, at least four lanes of Second Avenue remained open to traffic and efforts were made to maintain access to businesses and residences. Structural and ground improvement techniques were used to minimize ground settlement and to preserve the structural integrity of various facilities, including utility lines, buildings, tunnels, and ramps. Public tours were held to inform residents of the project's progress.

In subsequent phases of the project, the line will be extended south to Lower Manhattan and north to 125th Street.