Andrew Square to Dewar Street Reliability Project

As part of always working to serve you better, and to ensure that Eversource continues to reliably serve the City of Boston, Eversource is proposing to install a new, underground, 115-kilovolt (kV) transmission line.

The proposed 2.1-mile transmission line will connect Eversource's Andrew Square Substation to the Dewar Street Substation and be installed under streets in Dorchester and South Boston (see map below.) The proposed project also includes improvements within the existing fence lines of the substations. 

The project information presented on this webpage is also available in:

Energy Facilities Siting Board

To construct and operate the new 115-kV transmission line, Eversource must file a petition with the Massachusetts Energy Facilities Siting Board (EFSB) for approval. The petition filing is part of the regulatory review process, as defined by Massachusetts state statutes.

On March 1, 2019, Eversource submitted the following Siting Petition to the EFSB:

The EFSB held a Public Comment Hearing on June 26, 2019, in Boston, where individuals and groups affected by the initial petition were given the opportunity to voice feedback to the Siting Board.

The Siting Board conducted a remote Siting Board meeting using Zoom on June 30, 2021, at 1 p.m. to listen to comments and vote on whether to approve, approve with conditions or reject the project.

The Siting Board's Final Decision to approve the project was issued on July 2, 2021.


Click map to enlarge

Project Facts: 

  • Route length: Approximately 2.1 miles
  • City: Boston (Dorchester and South Boston), Mass.
  • Line voltage: 115,000-volt (115-kV) underground transmission line
  • Siting review by: Energy Facilities Siting Board (EFSB)
  • Public Open Houses: October 10 & 11, 2018
  • File Siting Petition with the EFSB: March 12019
  • EFSB Public Comment Hearing: June 26, 2019
  • EFSB Evidentiary Hearings: December 2019

Estimated Timetable (subject to change): 

  • Tentative Decision from the EFSB: June 17, 2021
  • Final Decision from the EFSB: July 2, 2021
  • Pre-construction information sessions: Beginning Third Quarter 2021
  • Start of construction*: Third Quarter 2022
  • Projected in-service date*: Fourth Quarter 2023

*  Pending all necessary siting and permit approvals

Traffic Management Plans

Construction Updates

Please know that Eversource takes every safety precaution while working in local communities, and that all people working on the construction project carry identification. The project work will not interrupt electric service to homes or businesses.

Eversource is committed to updating neighbors, businesses, and all community members about project activities, especially during construction. Please keep in mind that the construction schedule may change due to weather or other unexpected circumstances.

Week of August 8, 2022: 

  • Eversource crews will be excavating for the preparation of a ductbank installation within the Andrew Square Substation fence line at 45 Ellery Street. A ductbank is a protected pathway for buried electrical wires in which transmission lines will be placed.
  • This work will include the use of excavators, concrete cutting saws, and jackhammers.

Week of August 8, 2022:

  • There will be no work in MEM the week of August 8, 2022.

Week of August 82022:

  • There will be no work on Morrissey Boulevard the week of August 8, 2022.

Week of August 8, 2022:

  • There will be no work at Savin Hill the week of August 8, 2022.

Week of August 8, 2022:

  • There will be no work at Dewar Street the week of August 8, 2022.

Community Outreach

As the proposed project proceeds through the siting and permitting process, we will continue to engage town officials, residents, businesses, community groups and other stakeholders through municipal briefings, open houses, mailings and meetings – answering questions and listening to any feedback about the project.

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Contact Information

For more information about the Andrew Square to Dewar Street Reliability Project, send an email to or call 800-793-2202.