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Landowner Notices

Obtain information on pipeline issues concerning landowners.

Frequently Asked Questions (FAQ)
Click on a question below.
How does the PNGTS Pipeline work?
How long does a pipeline last?
How are Gas Pipelines regulated?
What can cause a pipeline accident?
What is "Digsafe?"
What does PNGTS do to promote safety?
How would I know if there was a problem on the pipeline?
What will happen if there is a leak?

If your question is not answered by one of the topics listed above, please feel free to e-mail us by clicking on the following link: [email protected]

General Overview

PNGTS transports natural gas safely and efficiently through its pipeline to paper mills, electric power producers, utilities, marketers and local businesses. Pipelines within the United States have a proven track record of being the safest way to transport energy. Although PNGTS was engineered and constructed according to stringent safety standards, it is important that we communicate with our neighbors about this important issue.

Common sense - and a basic understanding of how the pipeline works - will keep our system, and our neighbors, safe.

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How does the PNGTS Pipeline work?

Natural gas travels from producing regions in Canada to PNGTS's consumers through its high capacity pipeline. During transportation and storage, natural gas is compressed to save space. Current pipelines have the ability to compress natural gas to nearly 1,500 psi, but PNGTS operates closer to 1,100 psi. The PNGTS pipeline is made of high-strength welded steel and is designed to operate safely at pressures up to 1,440 psi. The pipe was tested at even higher pressure levels before being placed into commercial operation. However, because the gas is under high pressure, it is very important to protect the pipe from accidental scrapes and gouges through the use of the DigSafe system as well as periodic patrols of the right of way by PNGTS field personnel.

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How long does a pipeline last?

A properly installed, well-maintained pipeline can operate safely and efficiently for decades. The pipeline has been coated and protected against corrosion, and all welds have been x-rayed during construction. In addition, PNGTS regularly inspects the system for damage or deterioration. Sections of pipe can be removed and replaced, if necessary.

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How are Gas Pipelines Regulated?

As an interstate natural gas pipeline, PNGTS is regulated by the Federal Energy Regulatory Commission (FERC). Under the Natural Gas Act of 1938, FERC regulates both the construction of pipeline facilities and the transportation of natural gas in interstate commerce. In addition, FERC also regulates the transportation of natural gas as authorized by The Natural Gas Policy Act of 1978 (one of the first efforts to deregulate the gas industry). Pipelines must also comply with stringent safety regulations administered by the U.S. Department of Transportation (DOT). Of all transportation industries regulated by the DOT, including those utilizing highways, railroads, and air routes, the natural gas transportation industry has the best safety record.

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What can cause a pipeline accident?

The vast majority of pipeline accidents in the United States are caused by third-party damage, typically when someone excavates too close to the pipeline without proper notification to the pipeline operator or DigSafe. Fortunately, this type of damage is preventable - through the cooperation of our landowners and contractors working along the right-of-way. Call before you dig! DigSafe: 1-888-DIG-SAFE (1-888-344-7233)

Other factors that can cause a pipeline accident include construction material defects, internal pipe corrosion, external pipe corrosion, and natural disasters such as earthquakes, floods, and landslides. To increase safety and reduce the potential for a pipeline accident, PNGTS was designed and built with the following features:

High grade materials standard in the industry;

Fusion-bond coating of external pipe areas;

A cathodic protection system.

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What is "DigSafe?"

The DigSafe program is a one-stop shopping approach to help contractors and property owners locate underground utilities. Under Maine, Massachusetts, New Hampshire and Vermont law, DigSafe must be notified before any excavation occurs. DigSafe then notifies the appropriate utilities, and any underground facilities in the excavation area are located and marked by trained personnel. PNGTS operations technicians will monitor any excavation activities within the right of way at no charge to the landowner or contractor.

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What does PNGTS do to promote safety?

Safety is our number one priority!
PNGTS was designed and constructed to comply with stringent safety codes;
PNGTS is operated and maintained with an ever-present mission towards safety; and,

PNGTS regularly offers a comprehensive training program to local emergency responders to ensure that they know what to do -- and what not to do -- in the very unlikely event of an incident on the pipeline.

Pipeline Marker

To help identify the location of the pipeline, PNGTS has installed thousands of bright yellow pipeline markers along the right-of-way as follows:

In line-of-sight of one another;
On each side of roadways, railroads, and larger streams/rivers; and
At significant bends along the pipeline.


While PNGTS has taken great efforts to locate its markers accurately, they should never be relied upon for precise pipeline location.

It is a federal offense to move, destroy or otherwise tamper with pipeline markers.


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How would I know if there was a problem on the pipeline?


A slow leak may cause grass or other vegetation to change color or die. A significant leak may form what appears to be a dense mist above the ground over the pipeline and may even excavate some of the soil covering the pipeline. The mist is condensation formed when high-pressure gas is released into the atmosphere, chilling the surrounding air.


You may be able to hear a leak. Anything other than a very small leak may be very noisy as the gas escapes under high pressure.


A strong odorant is added to natural gas for safety. While wetlands and other natural phenomena can produce similar "rotten egg" type smells, the odor may be due to a natural gas leak.


us immediately if you think you see, hear, or smell anything suspicious on or near the right-of-way.

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What will happen if there is a leak?

A leak can result in a dangerous situation! PNGTS and local emergency personnel will respond promptly.

Until The Situation Is Under Control:

Keep away, and keep others away from the problem area until trained personnel communicate that it is safe to return;

Do not enter a building in which gas buildup is suspected;

Do not allow open flames or operate electrical devices in the presence of escaping gas;(telephones, doorbells, halogen lights, etc., can provide a sufficient spark to ignite gas);

Do not try to operate pipeline valves -- only trained personnel may operate pipeline controls and equipment.

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Portland Natural Gas Transmission System
One Harbour Place - Portsmouth, NH 03801 - Telephone: 603-559-5500 - Fax: 603-427-2807

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