No 7 Secaucus Extension Final Report - NYCEDC

No. 7 Secaucus ExtensionFeasibility Analysis Final Report2 PROPOSED NO. 7 SECAUCUS EXTENSION CONCEPTUAL ALIGNMENTAND CONSTRUCTION METHODSNew YorkThe proposed alignment to New Jersey would begin with two new tunnels diverting from theexisting No. 7 tunnels, which are currently under construction in Midtown Manhattan (see Figures1 and 2). Full alignment plans and profile drawings are included in Appendix C. These two newtunnels would be located just beyond the current double crossover south of the new West 34 thStreet Station in the tail track area for the No. 7 Extension to West 34 th Street and 11 th Avenue.Junction chambers would need to be constructed, enlarging the two newly constructed No. 7tunnels immediately south of where they cross beneath the existing Amtrak Hudson (North) Rivertunnels, which were completed circa 1910. The new tunnel enlargements would be locatedsouth of the existing Amtrak tunnels to avoid potential vertical conflict. The enlargements wouldrequire removal of the existing tunnel liners, excavation of additional rock surrounding the tunnel,and construction of new tunnel liners. Each No. 7 Secaucus Extension tunnel would include anew No. 10 turnout 3 and accommodate the movement of trains to and from New Jersey and toand from the newly constructed storage tracks beneath 11 th Avenue south of the West 34 thStreet Station.Figure 1:Proposed No. 7 Secaucus Extension New York AlignmentSource: Parsons Brinckerhoff, 20113 A Turnout refers to the speed trains are able to travel along a curve. In agreement with NYCT operations standards,a No.10 Turnout would allow trains to travel between 15 and 19 miles per hour (mph) through the switch within thetunnel.3