Mystic - East Eagle - Chelsea Reliability Project 

On February 16, 2022 Eversource filed with the Energy Facilities Siting Board an Initial Petition and an Application for a Certificate of Environmental Impact and Public Interest for issuance of 15 state and local permits required for construction and operation of a new electric substation in East Boston, which was approved in 2017 as part of the Mystic-East Eagle-Chelsea Reliability Project.

The Siting Board will conduct a remote Siting Board meeting using Zoom videoconferencing on Tuesday, November 29, 2022, at 9:30 a.m., and if necessary, resuming on Wednesday, November 30, 2022, at 9:30 a.m. 
The purpose of the Siting Board meeting is to listen to comments, deliberate, and vote on whether to approve, approve with conditions or amendments, or reject a Tentative Decision issued by the Siting Board.

For more information, send an email to or call 833-836-0302.

Electric demand is growing in eastern Massachusetts. The area needs an additional substation and transmission capacity to support the reliable delivery of electric power to meet the region's current demand.

At Eversource, we're always working to serve you better. We are installing a new substation in the East Eagle neighborhood of East Boston, and two new underground transmission lines to connect the new substation to existing substations in Everett and Chelsea.

We are also making minor improvements within the fenced area of the existing Mystic Substation on Broadway in Everett, and the existing Chelsea Substation on Willoughby Street in Chelsea.

The East Eagle - Mystic transmission line will be constructed under the streets in Chelsea and Everett, and connect to an existing duct bank connecting Chelsea and East Boston. (A duct bank is a group of tubes buried underground that is designed to house electric lines.) The East Eagle - Chelsea transmission line will be located within an existing duct bank and manhole system in East Boston and Chelsea.

Information about the project is also available in:


* Click to Enlarge

Substation site map - East Eagle St.

Project Facts:

  • East Eagle Substation: New substation on Condor Street in East Boston, Mass.
  • Route length: Approximately 5 miles
  • Cities: Boston, Chelsea and Everett, Mass.
  • Line voltage: 115,000 volts (115-kilovolt [kV])
  • Siting review completed by: Energy Facilities Siting Board (EFSB) and the Department of Public Utilities (DPU) in Massachusetts

Transmission Lines

  • Energy Facilities Siting Board (EFSB) approval for the transmission lines (EFSB 14-04/D.P.U. 14-153/14-154):  December 1, 2017
  • Start of construction on transmission lines: Second Quarter 2018
  • Transmission line in-service date: September 17, 2020 


  • Energy Facilities Siting Board (EFSB) approval for the Substation (EFSB 14-04/D.P.U. 14-153/14-154)December 1, 2017
  • File notice of Substation Project Change Petition with the EFSB: November 15, 2018
  • EFSB Notice of Substation Project Change, Tentative Decision: February 28, 2020
  • EFSB Public Comment Period on Substation Tentative Decision: Held on three dates:  December 16, 2020, February 8, 2021, February 9, 2021
  • EFSB approval for Substation Project Change (EFSB14-40A/D.P.U. 14-153A/14-154A): February 22, 2021

Construction Updates

First, 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 December 5, 2022: 

  • Eversource crews will be working at the substation located off Alford Street conducting upgrades. This work will be contained within the fence line.

Week of December 5, 2022:

  • There will be no work in Chelsea this week.

Week of December 52022:

  • There will be no work in Everett this week.

Community Outreach

Before starting construction in a community, we host public open houses to give local residents and business owners an opportunity to learn more about the project and ask questions of our subject matter experts.


Substation Enclosure Design Focus Group

As part of the EFSB's final decision, Eversource reinitiated the public engagement process for the design of the enclosure for the East Eagle Substation in East Boston.  At the direction of the EFSB, this process began with a focus group of residents and government officials, who provided feedback into the initial design of the enclosure.

Focus Group Meetings

2019 - 2020 Open Houses

The East Eagle Substation information session was held on February 5, 2019. Following the information session, the Energy Facilities Siting Board held a public comment hearing. Additionally, the East Eagle Substation Aesthetic Open House was held on January 14, 2020.

East Eagle Substation Facts and Frequently Asked Questions

Eversource representatives listened carefully to the community's questions and concerns during the January 14, 2020, open house. As promised during the open house, we developed "Addressing the Concerns of the Community," a document with project facts and frequently asked questions about the East Eagle Substation in East Boston.

We also created a short video that provides the history and an overview of the project.

2018 Open Houses

Open houses were held in Chelsea on February 8 and June 14, 2018; and in Everett on February 27, 2018. As we begin construction in the local communities, we will mail start of construction letters to property owners along the route, and conduct door-to-door outreach to nearby property owners, residents and local businesses. 

Customer Notifications

Boston City Council - Committee on City & Neighborhood Services

On Friday May 22, 2020, the City of Boston held a public hearing to discuss the approved East Eagle Street Substation; this matter was sponsored by Councilor Lydia Edwards and referred to the Committee on City and Neighborhood Services on January 29, 2020. During the hearing Eversource representatives listened intently and responded to the community's questions and concerns. As promised during the hearing, we're publishing our load forecasting graphics and our emergency response plan.

Traffic Management Plans

Working in consultation with town and state officials, including the Mass. Department of Transportation, Eversource has developed a set of Traffic Management Plans (TMPs) for each section of the Mystic - East Eagle - Chelsea Reliability Project.

The TMPs include conditions specific to routing as made by the EFSB in its final decision. The TMPs illustrate detailed site plans, showing underground line locations, hours of construction, area-specific traffic controls, and more.

Please note, TMPs are subject to change and may be updated.

Contact Information

For more information about the project, send an email to or call 833-836-0302