City Island Gas Distribution Crossing

CHA provided services for installing a new 8-inch HDPE HP carrier gas main in a 16-inch HDPE casing across a water body between City Island and the mainland Bronx, New York. The total installation length was approximately 1,200 feet and involved several agencies such as Parks, NYSDOT, and USACOE. CHA performed the initial site survey to gather existing condition data, establish horizontal and vertical control, and provide a basemap of the proposed route. A geotechnical exploration was performed to obtain soil conditions and test soils. Based on that information and utility research, and coordination with the local authorities and Con Edison, CHA provided engineered construction plans. There were two tie locations: one at the west end and one at the east end of the proposed route, both tying into new 8” transmission mains. The challenges of this project included:

  • Determination of the most cost-effective and efficient installation alignment to confirm constructability
  • Maintaining required clearances from existing utilities, such as UG electrical services, telephone, and UG gas
  • Maintaining allowable entry and exit angles to establish constructability through Horizontal Directional Drill
  • Protecting existing utilities
  • Maintaining the project schedule
  • Verifying all Con Edison specifications and engineering guidelines were met
Project Services:
  • Survey
  • Gas Engineering
  • Geotechnical Exploration and Engineering
  • Highway Engineering
  • Civil Engineering