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South Station Expansion - Study Update

Details about the project

Project Update

MassDOT Awarded Federal Grant for South Station’s Tower 1 Interlocking

In August 2019, the Massachusetts Department of Transportation was awarded a $41 million grant from the U.S. Department of Transportation to upgrade and improve South Station’s Tower 1 interlocking, a key element which distributes trains to and from the station that is used by almost 60,000 rail passengers daily. For more details on the award, see the MassDOT announcement.

MassDOT has completed the project’s Environmental Assessment (EA) and Finding of No Significant Impact (FONSI). MassDOT is now working with agency partners on potential early action projects. These could provide immediate benefits for operating South Station. They could be implemented in the near term and serve as stepping stones to completing the SSX project and other regional transportation improvements.

The complete redesign of the Tower 1 Interlocking at the South Station terminal is one of these projects. Tower 1 Interlocking is the railway “intersection” that provides operational flexibility for trains converging on South Station. It distributes each train to and from its platform track at the station. Several issues now limit Tower 1’s efficiency, such as physical constraints, more demands for service, and outdated equipment. MassDOT has prioritized redesigning Tower 1 as an improvement with immediate benefits for operating the current and future system.

The goal of the Tower 1 Early Action project is to address current reliability and resiliency issues. Potential elements of the project may include:

  • Replacing the existing signal system with a state-of-the-art microprocessor system
  • Addressing settling that has occurred at switch points
  • Providing conduits to allow easier access to wires and cables
  • Evaluating the ability to raise the tracks to remove an existing dip caused by ground settlement
  • Addressing ways to make Tower 1 more resilient to effects of climate change (flooding, extreme rain/snow events, heat stress, etc.)
  • Upgrading existing communications and providing redundancy
  • Evaluating the ability to host longer trains by extending the platforms

The Environmental Assessment

The Final Environmental Assessment (EA) and Section 4(f) Determination and the Finding of No Significant Impact (FONSI) for the South Station Expansion project can be viewed on the Documents page. The Federal Railroad Administration (FRA) and MassDOT issued the Final EA and Section 4(f) Determination and the FONSI on 10/27/2017.