Section 31 Transmission Line Rebuild

Central Maine Power (CMP) will begin rebuilding and modernizing its five mile Section 31 Transmission Line in Spring 2026, which serves Brunswick, Topsham, and parts of Harpswell. The line runs from the Topsham 115kV Substation near Crooker to the Brunswick West Side Substation on Barrows Drive. 

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Latest Update: April 22, 2026

 

  • Questions: please contact Project Outreach at 888-267-0831 or outreach@cmpco.com
  • Abutters: check your mailboxes in the coming days! A construction notice and project fact sheet have been mailed to 295 landowners and municipal officials.
  • Construction activities are now underway in Topsham. Crews are beginning to lay wood ground mats in environmentally sensitive areas. Mats protect the ground underneath them from damage due to the weight of construction vehicles.
  • Pre-construction reviews continue in the easement as we get locations prepared for construction. Landowners will see additional field crews, including environmental specialists, surveyors, and construction managers, conducting assessments.
  • Additional staking is planned. Earlier this month (April), stakes were placed to mark the easement borders. Next, stakes to denote new pole placements will be added to the easement.

Project updates and information

April 22, 2026:

  • Questions: please contact Project Outreach at 888-267-0831 or outreach@cmpco.com
  • Abutters: check your mailboxes in the coming days! A construction notice and project fact sheet have been mailed to 295 landowners and municipal officials.
  • Construction activities are now underway in Topsham. Crews are beginning to lay wood ground mats in environmentally sensitive areas. Mats protect the ground underneath them from damage due to the weight of construction vehicles.
  • Pre-construction reviews continue in the easement as we get locations prepared for construction. Landowners will see additional field crews, including environmental specialists, surveyors, and construction managers, conducting assessments.
  • Additional staking is planned. Earlier this month (April), stakes were placed to mark the easement borders. Next, stakes to denote new pole placements will be added to the easement.

Project Scope

Section 31 is a 50–60-year-old transmission line that in recent years has become more vulnerable to outages due to age and increased storm activity. We will build a new, modernized line to improve reliability, expand capacity to meet growing electricity demand, and support clean energy technologies such as electric vehicles and heat pumps.

We’ll build the new transmission line while keeping the old one in place and energized to avoid any service interruption; there will be no outages as a result of this work. The new line will use slightly taller steel poles and a covered wire that helps prevent tree-related outages. Once the new line is up and running, we’ll safely remove the old poles and wires.

 

Section 31 Transmission Line Route

 

Benefits to Customers

  • Replaces aging infrastructure
  • Expands capacity to meet growing electricity demand
  • Improves reliability to more than 8,000 customers in Topsham, Brunswick, and Harpswell
  • Enhances resiliency during major, stronger storms, such as those Maine has experienced in recent years 
  • Supports clean energy technologies such as heat pumps and EV chargers

 

Outages

Work will be completed without customers experiencing an interruption of service.

 

Work hours and noise

Most work will occur during daylight hours in accordance with town ordinances. Some night-hours work, particularly in the Topsham Fair Mall area, and across the interstate and the Androscoggin River, or weekend work may be required. All work is weather-dependent.

Construction noise will be present, including vehicle backup beeping sounds, heavy equipment vehicles, pounding, and other sounds associated with digging holes to install new structures.

 

Construction Zone Safety

At CMP, your safety and that of our crews are top priorities. Please follow construction signs regarding construction zones, path closures, traƯic pattern changes, or parking lot closures.

 

Visual Renderings

We have created visual renderings that depict structures and wires that will be installed in CMP’s Section 31 corridor. They do not show the final work on vegetation, fences, and other non-transmission structures.

Contact us

More information

CMP has a perpetual easement of 100 feet that has been in place since the 1950s. The current Section 31 transmission line is in the middle of the easement.

As part of the upgrade, a new line will be installed oƯset from the existing line and within the established boundaries of the 100-foot area. The easement does not change. The width and location of the existing corridor will remain the same. 

CMP crews will be accessing the transmission line corridor via roads where CMP has access rights or legal agreements with property owners or towns. CMP will contact some adjacent landowners to discuss access rights.

CMP will secure all necessary permits and approvals from the Maine Department of Transportation, MaineDepartment of Environmental Protection, U.S. Army Corps of Engineers, and Town of Brunswick.

CMP crews will lay wood mats in environmentally sensitive areas. The mats disburse the weight of construction vehicles to protect the land below them.

CMP positively collaborates with communities and recreation groups to balance safe access to our corridors with our need to reliably maintain the electric grid. Many of our Brunswick neighbors actively use paths in the Columbia Street area that are near our transmission line or cross its corridor. For your safety, we will keep you informed about construction activity. 

CMP’s Community Relations team is working with the Town of Brunswick and Brunswick School Department to send notifications, including letters, alerts, and posted signs. Also, we're coordinating our work around school and sports schedules, bus stops, and people walking to/from schools. Safety fencing will be used in some areas.