Hudson Transmission Project - New York

New York, NY

Project Highlights / Scope of Work:

  • Performed excavation and blasting for new underground cable transmission system
  • Installed transition pit carrying cables at Hudson River
  • Performed trenching and installation of 900 LF of concrete ductbank from West 52nd Street to Con Edison’s 49th Street Station
  • Drilled and blasted rock and installed 12’ x 72’ x 11’ precast concrete fluid vault for pressure equalization
  • Replaced 260 LF of water mains and catch basins
  • Demolished and replaced concrete slab at substation providing access to new ductbank
  • Installed cable rack system inside Con Ed substation
  • Performed backfill and restoration at 52nd Street and West Side Highway including asphalt and concrete paving of streets and sidewalks and steel-faced and granite curbing
Challenges:

  • High pedestrian and vehicular traffic in work areas
  • Numerous hidden utilities and obstructions at jobsites
  • Complex project involving five major city and state agencies requiring extensive coordination and scheduling
  • All work to conform to strict regulations set by NYCDOT, NYSDOT, NYCDEP, NYCDOB and Con Edison
Project Description:

The goal of the Hudson Transmission Project was to increase electrical power capacity to New York City by connecting the power grids of New York and New Jersey through a complex set of cables running both underground and under the Hudson River.  The resulting two-way capability of the underground cable system provides benefits on both sides of the Hudson including a new secondary power supply for Manhattan and substantial system upgrades in northern New Jersey.

The New York side of the job began with the drilling of a deep transition pit at the river bank enabling splicing into the new cable system.  An area at 52nd Street was drilled and rock blasted and a large precast concrete fluid vault was installed.  The water main and catch basins were replaced and fiber optic handholes and a link box were added.  Along the West Side Highway, trenching and excavation was performed and a new 900 LF concrete ductbank was constructed carrying the 345kV cables to the Con Edison Substation at 49th Street.  Inside the station an existing concrete slab was demolished and a new one was poured linking to the ductbank.  Cable stands, trays and grating were also installed in the interior.  All affected roadways, sidewalks and curbs were restored.

Several challenges arose throughout the project including the need to redesign the cable layouts as more and more underground utilities were encountered.  Work zones in close proximity to pedestrian and vehicular traffic required extra safety precautions and lane closures.  Five major city and state agencies were involved in the project making careful planning, scheduling and coordination a necessity.  In addition, the specific standards and regulations of each individual agency were adhered to throughout the work.

This project not only increased the reliability of the power supply in Manhattan but also provided extensive long term upgrades and reinforcements to the existing transmission system in New Jersey at no cost to the taxpayers.  The electrical cost savings and environmentally friendly improvements will have a positive impact on the area for years to come.