Transporting approximately 8.3 million people in the city that never sleeps is challenging. Congestion on crowded subway lines is common during morning and evening rush hours, and passengers rely on the Metropolitan Transportation Authority’s (MTA) 24 subway lines to take them where they need to go.
Commuters living on Manhattan’s East Side, however, lack a direct subway line in their neighborhood. This lack of direct access to areas east of Lexington Avenue contributes to the surplus of passengers riding the 4, 5 and 6 subway lines, which in turn causes delays and stress on infrastructure, and increases safety risks in bottlenecked stations.
In an effort to relieve excessive crowding currently prevalent on the Lexington Avenue subway, the MTA commissioned AECOM as the prime engineering and design consultant for the new Second Avenue Subway project, the first major expansion of the MTA New York City Transit (NYCT) subway system in more than 50 years.
Underground for their entire 8.5-mile length, the Second Avenue Subway’s twin tunnels run between Harlem in the north and Hanover Square in the south. Transfers to existing stations are being evaluated to increase the line’s usefulness, and improve overall system connectivity and flexibility. AECOM’s experts designed 16 new station entrances to take advantage of natural light and increase tunnel ventilation. They incorporated alternative energy sources such as an aluminum third rail engineered for greater energy efficiency.
The team also used construction techniques such as tunnel boring machines (TBM), cut-and-cover, and mining on the project’s first phase, which stretches between 96th Street and connects with the existing 63rd Street line, including stations at 96th, 86th, and 72nd Streets — and is now in final design. Work for each station, the TBM tunnels and the systems were prepared using multiple contracts.
The initial operating segment under Contract No.1 – TBM tunnels from 92nd Street to 63rd Street – was completed and started revenue service in 2016.
“The Second Avenue Subway project is being built in one of the most densely populated and challenging environments in the world,” says AECOM’s Richard Paupst, vice president, Transportation. “In a city that never sleeps, we are constantly working among people and traffic.”