Bergen Tunnel Laser Scan

The Bergen Tunnel, 4,400 feet long, is part of one of New Jersey’s first historic railways. The Long Dock Company, incorporated February 26, 1856, in the interest of the Erie Railway Company, completed the Bergen Tunnel January 28, 1861. 

Weber Surveying, Inc., contacted Erdman Anthony to provide a means to verify clearance limits during this railroad tunnel enlargement project. The Conrail Bergen Tunnel was to undergo replacement of rail tracks and tunnel liner as well as tunnel clearance improvements. It was necessary for the contractor to have detailed profile drawings, well-defined clearance, and cross sections to verify proper clearance limits prior to track installation. Erdman Anthony coordinated closely with RJ Corman Construction as the tunnel was enlarged. Various sections of the tunnel were scanned as liner installation and rock removal were completed. Additional coordination with Weber occurred as our crews laid out set control points (SCP) for Weber to survey. SCP documentation, including sketches and stationing, was provided to Weber. RJ Corman Construction used the scanning as verification that the minimum clearance had been achieved between the improved tunnel roof and the theoretical track grade line.

Minimum vertical scanning limits were set to “tunnel ten o’clock to two o’clock.” Scanning began at Station 98+56 and finished at Station 140+16. Scans were completed approximately every 200 feet with three to four targets at each site. Point density was completed at 1” x ½”. The project required our crew to maintain high safety standards under conditions that included dust, mud, slick surfaces, and dark areas.

Project Details

Location

Jersey City, NJ

Owner

Conrail

Project Contact

Bryan Merritt, PSM/LS
  • Bryan Merritt, PSM/LS
  • 561-753-9723 x 6017
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