MJ provided survey and mapping services to D.A. Collins Family of Companies during the construction of this extensive rail tunnel project, which replaced two nearly 100-year-old rail bridges in the center of the Town of Middlebury. The aggressive schedule required MJ to provide around-the-clock survey stakeout services for six straight weeks. The expedited schedule was important to minimize downtime for rail, commuter and commerce traffic.

In addition to conventional survey, MJ conducted 3D laser scanning during construction. The data was incorporated into our in-house MJ4D software to monitor construction progress.

The new rail tunnel is made of 422 pieces of precast concrete U-walls, each piece weighing roughly 40 tons. The 360-foot tunnel addressed several deficiencies and provides vertical clearance for double-stack rail cars.