Subway FAQ: Interconnections Between IRT and IND-BMT Divisions
Due to the difference in tunnel clearances, the IRT and BMT/IND lines are operated separately. However there are some places where the former IRT lines and former BMT/IND lines connect. These are mostly used for work and revenue collection trains (which are IRT sized), and for moving IRT passenger cars to shops on the IND/BMT lines (Coney Island Overhaul, 207th Street Overhaul) for maintenance. The connections are:
- A one-track connection between the IRT #3 (New Lots Line) and the BMT "L" Canarsie line near the Junius St. Station, for Linden Yard access. There is no third rail on this connection. The yard is normally used for work trains powered by diesel locomotives.
- A diamond crossover on the upper level of Queensboro Plaza, between the N and the 7. This connection is the #7 line's sole connection to any other line in the system and is used for bringing #7 cars on and off the line for maintenance (or delivery of new cars).
- Yard leads connect the Concourse Yard to the #4 line just north of Kingsbridge Road station and to the Concourse Subway just south of 205th Street.
- Yard leads connect the 207th Street Yard to the #1 line north of 207th St station and to the 8th Avenue IND subway.