In a historic tunnel south of Grand Central Station, L.K. Comstock and RailWorks Transit crews replaced the Vanderbilt circuit breaker house (CBH) that powers NYCT's Flushing (7) Line. Thanks to a combination of old-fashioned hard work, creative engineering and scheduling, the team wrapped up work five months early.
Work on the $6 million Vanderbilt CBH project began in December 2013 under the direction of Project Manager Joe Ciaccio. The project site included the existing substation at street level, on Park Avenue between 41st and 42nd streets in New York City, and the tunnel underneath, in old section of the 7 Line known as the Steinway Tunnels (constructed in the 1890s by piano magnate William Steinway).
“The first challenge was gaining access to the track,” reports Joe. “A temporary 85-foot scaffold was installed inside the vent shaft to gain access from the street to the work area.”
The next major hurdle was how to connect the cables from the substation to a new circuit breaker house at track level and run them to the third rail on the track. “It took ingenuity and engineering to make it happen,” attests Joe.
L.K. Comstock installed new cables from the existing substation at street level via the new electrical duct bank, then down the vent shaft to the new CBH at track level. Crews also installed new cables on the subway tracks on the 7 Line, which feeds traction power from the CBH to the new third rails. RailWorks Transit crews constructed the building for a larger, new CBH enclosure to house upgraded traction power equipment.
Much of the electrical and track work was completed over weekends during In-Services, when subway service is suspended so crews can gain access to the track, reports Joe. “The Transit Authority used the In-Services to get a tremendous amount of work done, so we had to coordinate around other contractors working in the tunnel.”
The project team began coordinating with NYCT’s Third Rail Operations and Traction Power departments about five weeks in advance of the final In-Service. Over the weekend of March 21 through 23, 2015, L. K. Comstock energized, tested and successfully put the new CBH into service.
Due to its focus on NYCT and its customers who ride the 7 Line, the L.K. Comstock-RailWorks Transit project team delivered the job early, a rare accomplishment for the NYCT.