(the Second Avenue Subway (officially the IND Second Avenue Line; abbreviated to SAS) is a New York City Subway line that runs under Second Avenue on the East Side of Manhattan)
The first phase of this new line opened on January 1, 2017, serving a projected 200,000 daily riders at three new stations between 96th Street and the 63rd Street Lines before connecting to the BMT Broadway Line and the rest of the subway system.
The full Second Avenue Line, if and when funded, is planned to be built in three additional phases, allowing new portions to open before the entire line is completed between 125th Street and Hanover Square.
The proposed full line would be 8.5 miles (13.7 km) long with 16 stations and a projected daily ridership of 560,000, costing more than $17 billion.
The line was originally proposed in 1919 as part of a massive expansion of what would become the Independent Subway System (IND).
Work on the line never commenced, as the Great Depression crushed the economy.
Numerous plans for the Second Avenue Subway appeared throughout the 20th century, but these were usually deferred due to lack of funds.
The line was proposed to replace the Second Avenue and Third Avenue elevated lines.
Although the new subway was not built, the elevated lines were demolished in 1942 and 1955, respectively.
This left the Lexington Avenue Subway as the only rapid transit line on much of Manhattan’s east side; it is by far the busiest subway line in the United States, with an estimated 1.3 million daily riders as of 2015.
Construction on the Second Avenue Line started in 1972 as part of the earlier Program for Action, but was halted in 1975 because of the city’s fiscal crisis, with only a few short segments of tunnels having been completed.
Construction work on the 63rd Street Lines, which would connect the Second Avenue Line and the IND Queens Boulevard Line to the BMT Broadway Line and the IND Sixth Avenue Line, had started in 1969, and work on the 63rd Street Lines continued even after construction on the Second Avenue line ended.
The first segment of the 63rd Street Lines, which opened in October 1989, included provisions for future connections to the Second Avenue Line.
Work on the line restarted in 2007 following the development of a financially secure construction plan.
The Metropolitan Transportation Authority (MTA) awarded a tunneling contract for the first phase of the project to the consortium of Schiavone/Shea/Skanska (S3) on March 20, 2007.
This followed preliminary engineering and a final tunnel design completed by a joint venture between AECOM and Arup.
Parsons Brinckerhoff served as the Construction Manager of the project.
A full funding grant agreement with the Federal Transit Administration for the first phase of the project was received in November 2007.
A ceremonial ground-breaking for the Second Avenue Subway was held on April 12, 2007.
The first phase of the line, consisting of three newly-built stations and two miles (3.2 km) of tunnel, cost $4.45 billion.
A 1.5-mile (2.4 km), $6 billion second phase is in planning and is expected to open by 2027–2029.
Phase 1 is served by the Q train, which runs at all times.
The N provides limited rush hour service on phase 1.
A second phase is planned to extend the line from 96th Street to 125th Street, and both the N and Q will be extended to 125th Street when Phase 2 is built.
A new T train will serve the entire line from 125th to Houston Streets at all times when phase 3 is built.
The T will be extended to Hanover Square upon Phase 4’s completion.
(the T will be colored turquoise since it will use the Second Avenue Line through ‘Midtown Manhattan’)