South Station Expansion – Tower 1 Interlocking

Rail/Transit, Rail
Bid Build
Boston, MA
Massachusetts Bay Transportation Authority

Middlesex is rebuilding and upgrading Tower 1 Interlocking and Cove Interlocking. Scope includes sitework, trackwork, structural, power, lighting, signals, and communication work.

Tower 1 interlocking area: (1) Replacement of trackwork. (2) Foundation & platform for a new 60ft x 10ft central instrument house. (3) Upgrading of the existing relay based signal system with a microprocessor based signal system. (4) Replacement of existing back-up power generator from 150kVA to 300kVA. (5) New lighting & replacement of floodlights. (6) Additions to the communications & security systems. (7) Replacement of trackwork & associated signal infrastructure within the Cove interlocking area.

By the Numbers

$2M
Civil Work

$13M
Track Work

electrical_services

$34M (35% of Project Value)
Electrical Work

attach_money

$98.6M
Project Value

Scope of Work
  • End of the line layover facility
  • System installation
  • Positive train control
  • Program-wide signals and communications systems
  • Electrical Signal/Systems/PTC
  • Track work
  • Civil Work / Drainage / Culverts
  • Retaining Walls
Unique Challenges
  • 5 year project – most completed during 105 weekends of closure from 10PM Friday – 6AM Monday
  • No track work was allowed from December 1st to March 15th
The Middlesex Corporation is rebuilding and upgrading the South Station Tower 1 Interlocking for the Massachusetts Bay Transportation Authority (MBTA) in Boston, MA. The bid build project includes replacement of trackwork, installing the foundation and platform work for a new central instrument house, upgrading the existing relay-based signal system, replacing the existing back-up power generator, installing new lights and floodlights, additions to the communication and security systems, and the replacement of trackwork and associated signal infrastructure within the cove interlocking area.
The Middlesex Corporation is rebuilding and upgrading the South Station Tower 1 Interlocking for the Massachusetts Bay Transportation Authority (MBTA) in Boston, MA. The bid build project includes replacement of trackwork, installing the foundation and platform work for a new central instrument house, upgrading the existing relay-based signal system, replacing the existing back-up power generator, installing new lights and floodlights, additions to the communication and security systems, and the replacement of trackwork and associated signal infrastructure within the cove interlocking area.
The Middlesex Corporation is rebuilding and upgrading the South Station Tower 1 Interlocking for the Massachusetts Bay Transportation Authority (MBTA) in Boston, MA. The bid build project includes replacement of trackwork, installing the foundation and platform work for a new central instrument house, upgrading the existing relay-based signal system, replacing the existing back-up power generator, installing new lights and floodlights, additions to the communication and security systems, and the replacement of trackwork and associated signal infrastructure within the cove interlocking area.
The Middlesex Corporation is rebuilding and upgrading the South Station Tower 1 Interlocking for the Massachusetts Bay Transportation Authority (MBTA) in Boston, MA. The bid build project includes replacement of trackwork, installing the foundation and platform work for a new central instrument house, upgrading the existing relay-based signal system, replacing the existing back-up power generator, installing new lights and floodlights, additions to the communication and security systems, and the replacement of trackwork and associated signal infrastructure within the cove interlocking area.
The Middlesex Corporation is rebuilding and upgrading the South Station Tower 1 Interlocking for the Massachusetts Bay Transportation Authority (MBTA) in Boston, MA. The bid build project includes replacement of trackwork, installing the foundation and platform work for a new central instrument house, upgrading the existing relay-based signal system, replacing the existing back-up power generator, installing new lights and floodlights, additions to the communication and security systems, and the replacement of trackwork and associated signal infrastructure within the cove interlocking area.
The Middlesex Corporation is rebuilding and upgrading the South Station Tower 1 Interlocking for the Massachusetts Bay Transportation Authority (MBTA) in Boston, MA. The bid build project includes replacement of trackwork, installing the foundation and platform work for a new central instrument house, upgrading the existing relay-based signal system, replacing the existing back-up power generator, installing new lights and floodlights, additions to the communication and security systems, and the replacement of trackwork and associated signal infrastructure within the cove interlocking area.

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