Interlockings: Vital to Third Track

Nassau Interlocking 10-16-20

We all know the end game for the LIRR Expansion Project is getting that third track laid between Floral Park and Hicksville. In the meantime, MTA Construction & Development and LIRR crews are working along the Main Line right-of-way to prepare for the track installation with one of the most critical pieces of infrastructure: interlockings. These will enable the LIRR to reap all the benefits of the additional track, comprised of a series of switches making it possible to move trains from one track to the other.

Nassau Interlocking 10-16-20

In recent months, C&D has been working to install two interlockings – Nassau 1, just east of the Merillon Avenue station, and Nassau 3, east of the Mineola station. Much of this work is conducted during double track outages to allow crews unencumbered access to the right-of-way.

Nassau Interlocking 10-16-20

Work on Nassau 1 began about a year ago with the shifting and raising of the tracks. C&D installed the interlocking’s switches during double track outages from November 2019 through March 2020. Wiring for signals and train control is underway and expected to be completed next year, along with the cutover to the new interlocking. The installation of the third track in the area will be installed in the summer of 2021.

Nassau Interlocking 10-16-20

A similar process is being followed for Nassau 3, with the track raise completed this past spring. Wiring for signals and train control and switch installation is ongoing. Crews will take advantage of additional double track service outages this fall to continue the interlocking installation.

Once the LIRR Expansion project is complete, the interlockings and third track will provide the railroad with the ability to increase service by nearly 50 percent, route trains around problem areas and provide true bidirectional service during peak morning and afternoon periods.