The
IND Second System was proposed in September of 1929, while work on
New York City's
Independent subway system was still underway. It was to add 100 miles of track to the New York City
subway system, at an estimated cost of $800 million dollars.
Of course, before any of this could happen, the stock market crashed in October of 1929. The Second System was dead on arrival. But small pieces of it were actually built-- those that connected with the Independent-- and some of the lines proposed may someday be built.
Lines of the Second System:
The Second Avenue Subway. In its original incarnation, the 2nd Avenue Line began at Hudson Terminal underneath the present-day World Trade Center complex, and looped around the Battery before heading uptown on 2nd Avenue, with connections to the outer boroughs. The line was to be 6 tracks between 61st Street (where two tracks diverged to connect with the 6th Avenue subway) and 125th Street. Rumor has it that a more modest version of the 2nd Avenue line will be built in the next few years, between 63rd and 125th Streets, though where the money will come from is anyone's guess. Ground was actually broken on a few short, unconnected stretches of tunnel in the early 1970s.
Two new Manhattan-Brooklyn river crossings were to be built, both tunnels, at Houston and Worth Streets. The Houston tunnel would feed the 6th Avenue subway, and the Worth tunnel the 8th Avenue. Both lines would meet at South 4th Street junction in Brooklyn.
Two new Brooklyn-Queens lines would radiate from South 4th Street. One line would extend in a southeasterly direction, and follow Utica and Nostrand Avenues to Sheepshead Bay. The IRT Nostrand Avenue subway was to be extended to Avenue S to connect with the new line. The other would head northeast to a junction with the Long Island Rail Road's Montauk Branch, which would be annexed for subway service. The line would continue eastward to the Rockaway Branch, which would also be annexed. A connection to the Queens Blvd. subway was to be provided. South of Liberty Avenue, service would be identical to today's Rockaway service, with two exceptions. The Rockaway Park branch would be extended to Jacob Riis Park along Newport Avenue, and a branch would serve southern Queens along Conduit and 120th Avenues.
The Fulton Street Line (at this point constructed only as far as Broadway-East New York) would be extended onto the Fulton Street el. This actually happened, though the Second System would have used more of the elevated structure. Also, the el was to be extended far past its current terminal at Lefferts Blvd.-- 6 more miles to Springfield Blvd. and Hollis Avenue in Springfield Gardens, with connections to the Jamaica el and other, to-be-built lines.
In Queens, a subway would be built alongside the Van Wyck Expressway. It would connect all the major lines of southern Queens-- the Queens Blvd., Jamaica, Liberty Ave., and 120th Avenue lines. Instead, along this route, we got a stupid monorail to Kennedy Airport that connects with NOTHING.
The Flushing Line (7 Train) was to be extended to College Point via 149th Street, and to 221st Street in Bayside, paralleling the LIRR Port Washington Branch.
The Astoria Line (N Train) was to be extended north-east to serve LaGuardia Airport. Then it would have followed the Grand Central Parkway to Flushing Meadow Park, where it would have turned east, and followed the Long Island Expressway, terminating at Francis Lewis Blvd.
In the Bronx, the Second Avenue Subway would continue under Boston Road, branching into two different lines. One would run over the IRT's White Plains Road el, which would be modified to IND standards. The other would run north-easterly to Co-Op City. The First System Grand Concourse subway would be extended eastward to meet the Co-Op City Line.
Admittedly, a street map of New York City is necessary to fully appreciate the implications of this. The intention was to provide complete subway service to the outer boroughs.
Vestiges of the Second System can be seen in several locations. One is the Roosevelt Avenue station on the Queens Blvd. line. At the north end of the station mezzanine, there is a passageway-- off limits, of course-- that leads to a platform built for the Rockaway connection that never happened. There are also tunnel bell mouths near the Woodhaven Blvd. station built for a later version of the Rockaway connection. There are rumors of a never-used subway tunnel under Woodhaven Blvd., but no proof.
Also, at Utica Avenue on the A Train, there are trackbeds cut into the station ceiling at an angle. This was for the Utica Avenue subway that was to stop on the upper level of the station.
Part of the gigantic South 4th Street station complex was built in downtown Brooklyn. Supposedly, there is access from the Broadway station on the G, but unless you have friends who are transit workers, it's tricky.
Source: http://www.nycsubway.org