South Station Signal and Track Improvements Project
The South Station Signal and Track Improvements Project will focus on the Tower One interlocking and Cove interlocking, which control all rail traffic in and out of South Station, the second largest multimodal transportation facility in New England.
We’re upgrading the Tower One track and signal system and the Cove track system to improve the reliability of service at South Station. This work will also support future growth of the MBTA and Amtrak. We are using Widett Circle to stage materials and equipment for the critically important Tower One project, which is under construction.
Design contract awarded: January 2021
Construction contract awarded: May 2023
Projected completion: Early 2028
Budget: $169 million
Status: Construction started in May 2023
Building a Better T
As part of our $9.6 billion, 5-year capital investment plan, we're renovating stations, modernizing fare collection systems, upgrading services for our buses, subways, and ferries, and improving the accessibility of the entire system.
Why We’re Doing this Work
Tower One Interlocking
The existing Tower One signal system is outdated and sometimes causes service interruptions—due to the number of trains traveling through the interlocking, even a 5-minute shutdown can create residual delays. At Tower One interlocking, we will:
- Replace the existing master signal system with a new signal instrumentation house that will manage all rail traffic in the South Station interlocking
- Replace all of the major interlocking track switches, interconnecting tracks, power systems, lighting, and security features
- Replace the existing switch heater system for the train tracks with a state-of-the-art, wirelessly controlled system
- Address settling that has occurred at switch points
- Replace generators to support power loads required by today’s equipment
Cove Interlocking
The trackwork at Cove interlocking is nearing the end of its service life. To ensure reliable train routing continues, we will:
- Replace the top and bottom layers of track bed
- Replace all of the major interlocking track switches, interconnecting tracks, power systems, lighting, and security features.
Photo Gallery
New train rails approaching Switch 65 (September 2024)
Crews work on panel prefabrication for double slip switch installation (September 2024)
Crews install track lead connection for double slip switch (September 2024)
Crews lift panels under the South Station busway ramp (September 2024)
Crews lift panels under the South Station busway ramp (September 2024)
Crew excavates a track bed for a new switch (August 2024)
Crew removes an old switch and excavates the site to its proposed depth (August 2024)
Crew places stone ballast on a new switch (August 2024)
Crew installs a duct bank for new signals (August 2024)
Crew installs new tracks at Switch 75A during weekend construction (June 2024)
Crew drills rail joints into new tracks (June 2024)
This arrangement of signals ensures the safety of all South Station trains as they move across junctions.
Tower One interlocking is just south of South Station and controls the movement of trains traveling to and from the terminal.
Contact Us
For questions and comments related to the South Station Tower One Interlocking Project, please contact Tower1SSX@mbta.com.
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Related Projects
Building a Better T
As part of our $9.6 billion, 5-year capital investment plan, we're renovating stations, modernizing fare collection systems, upgrading services for our buses, subways, and ferries, and improving the accessibility of the entire system.