Colonial Road Design / Build Improvement Project

Long Island, NY

Project Highlights / Scope of Work:

  • Replaced 120 year old 120’ long steel truss bridge with 324’ long precast concrete bridge
  • Extended and realigned roadway traveling over bridge
  • Constructed new twelve car pocket track
  • Constructed 1,600 LF of new retaining walls
  • Installed drainage upgrades including 2,400 LF of below-grade HDPE piping
  • Performed sitework
  • Received the American Society of Civil Engineers (ASCE) Metropolitan Section 2017 Design/Build Project of the Year Award for recognition of excellence in the successful completion of a major design/build project


  • Accelerated timeframe with road closure limited to one year
  • Restrictions on power shutdowns by PSEG Long Island
  • All work to be performed around train schedule with only limited outages permitted
  • Jobsite in confined space of suburban neighborhood causing logistical problems for delivery and staging
Project Description:

Railroad Construction Co. has completed a $25 million contract for the Metropolitan Transportation Authority-Long Island Rail Road in the Village of Thomaston, LI.   The massive Colonial Road Design / Build Improvement Project is a critical investment in the future of MTA-LIRR operations designed to provide long term bridge safety, improve the reliability and convenience of the train schedule and reduce flooding problems that have hindered service in the past.  Included in the job is the construction of a new bridge, roadway overpass and approaches and extension of the existing pocket track.

The focal point of the project was the demolition and replacement of the original steel truss bridge which was constructed in 1897 and was considered to be “functionally obsolete” by the Department of Transportation.  The existing 120’ long structure was removed in three sections using a 300 ton crane.  One weekend outage was required to complete the removal.  The new structure is made up of eighty-four precast concrete arch units, each with a 52’ long span.  Due to their size, each arch was delivered to the site on a separate oversized truck.  The space to accommodate these trucks plus the crane in a residential neighborhood as well as the timing of the deliveries created quite a logistical problem.  By obtaining access to several local church, school and town-owned parking lots, we were able to arrange staging areas for the vehicles which then followed a strict schedule into and out of the site.  Every effort was made to minimize our presence in the community.

The new roadway over the bridge was another major element of the contract.  Grading was performed and retaining walls were built before the roadway and approaches were extended an additional 200’.  The new alignment was designed to tie-in seamlessly to the existing route.

Extensive track work was also performed.  A new 2,000’ long pocket track, capable of storing twelve train cars, was constructed.  Major upgrades to the existing track’s drainage system were included.  The newly installed 2,400 LF of below-grade HDPE piping is designed to alleviate the ongoing flooding problem that has disrupted train service for years. 

These improvements will provide the MTA-LIRR with a host of benefits for years to come.  The new pocket track will enable the LIRR to provide better rush hour service and make it possible to turn trains faster than in the past.  Additionally, the track upgrades will enable the routing of more trains to the East Side of Manhattan once the East Side Access project is completed in 2022 while the new Colonial Road tie-in will enhance vehicle safety in the surrounding area.