The New York City Transit Authority is celebrating a subway breakthrough—literally. NYCT announced that the first of two 1,000 ton tunnel boring machines has completed its 4,661 foot run to a chamber adjacent to the current terminus for the No. 7 train underneath 42nd Street in Manhattan.
An initiative strongly backed by Mayor Michael Bloomberg and funded by the city, the $2.1 billion project will extend the No. 7 line to 34th Street and will support the growth of a new community emerging on the West Side in Midtown.
The tunnel boring machine broke through into the 200 ft. x 50 ft. x 40 ft. deep receiving chamber just below the Port Authority Bus Terminal close to the bus terminal foundation and utilities, as well as the 8th Avenue Subway Line. This is where the new tunnels will connect with the existing No. 7 Line terminus at Times Square.
The second TBM will break through and reach the chamber by the end of July.
Together, the TBMs have traveled approximately 8,600 feet out of a total 9,388 feet, over 90% of their journey. The TBMs will be partially disassembled and backed up to where they started tunneling at 26th Street and 11th Avenue, where they will be lifted out of the shaft.