In 2011 Unitil embarked on one of the largest, most aggressive capital improvement projects in Company history: the replacement and/or upgrading of over 100 miles of natural gas pipeline throughout Portland and Westbrook, Maine. The pipeline replacement project will modernize the gas system Unitil inherited from Northern Utilities and allow the system to meet the growing demand for natural gas in Maine

The project includes 68.5 miles of cast iron and/or steel pipe replacement and 36 miles of pressure upgrades for existing low-pressure plastic pipe. By replacing older cast iron pipes with state-of-the-art plastics, the system will be able to operate at a higher pressure reliably, assuring Unitil will be able to grow its business throughout coastal Maine. As an added benefit, the replacement project gives Unitil the opportunity to make its system safer and to replace aging pipes before they become a concern. We will also use the opportunity to install additional automated shut-offs to 10,000 of our customers in the greater Portland area in order to help keep homeowners safe in the event of a widespread gas outage. 

Are you doing this replacement because the current cast-iron pipeline is unsafe?

No. We are doing this project to modernize the system and allow it to grow so it can continue to meet demand in the area. An added benefit to this project, however, is we will be able to replace some of the older portions of the distribution system before they have the potential to become a serious safety concern.

As a customer, what are the benefits to me?

A modern system ready for the 21st century. By giving the infrastructure an upgrade to new materials, we will be able to improve the reliability of the system in a number of ways, including improved protection from third party damage, the number one cause of leaks. We will also be installing new shut-off valves as part of the plan; In the event of an expected pressure change in the line, these valves will help protect customers even further.

Why will it take 14 years?

Pipeline replacement is a complex, labor-intensive endeavor. It is not uncommon for smaller projects than what is proposed for Portland to take significantly longer than 14 years. The plan approved by the Maine Public Utilities Commission will be the largest of its kind in the northeast, and we are confident we will be able to get the project done in the time we’ve allotted.

When are you going to conduct replacement on my street or in my neighborhood?

We will keep our customers informed through a website dedicated to the project and direct communication with customers as they are impacted.  We encourage you to visit for construction updates, traffic advisories, news and other project information. 


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