The Second Avenue Subway (SAS) is one of the most prolific plans of the IND Second System, and one of the most notorious proposed subway lines in New York City. For nearly a century, before the 2nd Ave Elevated was even demolished, New Yorkers have been promised a full length SAS. The history of SAS serves as a great summary of the IND Second System plans overall: big plans, small budget. This post will focus on the initial attempt at construction of SAS, and the next will focus on the recent construction.

In the 1929 Second System plan, the city proposed an enormous full length 2nd Ave line, starting in lower Manhattan (connected to a new line in Brooklyn via a new under-river tunnel), and running up north to the Bronx (through another new under-river tunnel). This line would have a greater capacity than any other line ever built before it, with 4 tracks for most of the line, and 6 tracks on the portion from 61st St to 125th St. SAS was put on hold when the Great Depression hit, and the plans didn’t gain enough momentum for revival until after the predecessor to the MTA—the Board of Transit, and later the Transit Authority (TA)—was formed.

The 60s marked a new era for the TA with the construction of the Chrystie St Connection, and in 1968 came the Program for Action. This provided for the construction of SAS and the 63rd St tunnel, which was interwoven with the SAS plans. Finally, in the early ’70s, SAS construction commenced. Ground was broken for the first segment in October 1972, and a few other segments soon followed. Three of these segments were completed: 99th-105th St, 110th-120th St, and Canal St-Chatham Sq, and they lie dormant to this day. These tunnels are lit 24/7 and actively maintained by MTA NYCT. They serve as a somewhat spooky reminder of the ambitious NYC infrastructure plans from long ago. When the fiscal crisis of 1975 hit, construction on SAS was halted indefinitely. The other projects of the time, the 63rd St tunnel and the Jamaica Extension, were completed, though not in a timely manner.

The former 2 of the completed segments will play key roles in the current Phase II construction of SAS, which is slated to start as soon as the money comes in. It might take a while.