Gas Pipeline Safety - Overview

The PURA is committed to ensuring that gas transportation systems in Connecticut are designed, built, operated and maintained safely. The PURA requires gas pipelines to meet or exceed industry and government standards.


Design requirements specify that only top quality steel and welding techniques, or top quality plastics and joining methods, are used throughout Connecticut. To protect against corrosion, all new steel pipelines are coated. Also, a very low-voltage electrical current is applied to the steel pipe to provide cathodic protection against corrosion.

After construction, all pipelines are filled with air or water and pressure tested to ensure there are no defects.

Larger intrastate and interstate operators use advanced computerized systems to monitor and control their pipeline facilities. Interstate transmission pipelines have valves in the pipeline at specified intervals. Some are automatically activated by a pressure drop in the pipeline which may be caused by a leak. Other pipelines have remote sensors and remote control valves by which pipeline operators can detect problems and shut down the pipeline. Intrastate operators have valves throughout their system to control the flow of gas. Some of these valves are remote controlled while others are manual.

While safety is an integral part of the design, construction, operation and maintenance of pipeline facilities, each transmission pipeline is required to have a specialized Integrity Management Program (IMP) in areas of high population density and certain other areas. In practice, all the main interstate transmission lines in Connecticut are subject to electronic in-line inspection devices, known as "smart pigs" which are sent through the pipeline system to detect defects.  Local gas distribution companies monitor their systems for safety and are subject to a new set of requirements called Distribution Integrity Management to address IMP for their facilities.

One of the major threats to gas pipelines is damage by excavation activity. That is why Connecticut has one of the premier excavation damage prevention programs .

Federal/State Pipeline Safety PartnershipOffice of Pipeline Safety logo
Safety jurisdiction over gas pipelines was originally the responsibility of the States. With the passage of the Pipeline Safety Act of 1968, the federal government entered the arena of pipeline safety. The result is a federal/State partnership.

Intrastate Facilities
Jurisdiction for the safety of intrastate pipelines – those that engage in commerce strictly within the State – rests with the State. The intrastate pipelines in Connecticut include Connecticut Natural Gas, Southern Connecticut Gas Company, Yankee Gas and Norwich Department of Public Utilities which operate gas distribution systems (commonly referred to as Local Distribution Companies or LDCs) and certain propane systems (for more information, see the questions on the main Gas Pipeline Safety page). They are required to meet the Minimum Federal Safety Standards (49 CFR 191, 192, 193 and 199) promulgated under federal law (49 USC Chapter 601) and Regulations of Connecticut State Agencies (§16-11-1 et. seq.) established in accordance with Connecticut law (§16-1, et. seq.) .  Failing to follow these requirements is considered a violation of safety standards and can result in civil penalties.  View a list of violations and civil penalties.

Connecticut distribution operators receive gas from interstate transmission pipelines and distribute the gas to retail customers. Pipelines, called mains, run down streets to distribute the gas throughout the area. Smaller service lines run from the mains to the individual customers.

Some of the distribution facilities are very old and were not installed using what are now state-of-the-art materials, nor were they installed using state-of-the-art methods. Some of these older facilities are still providing safe and adequate service, while others are reaching the limits of their useful lives. A risk-based replacement program is addressing those issues.  Other facilities are newer and were installed with state-of-the-art materials and construction techniques and should provide safe and adequate service for the foreseeable future.

State and federal safety requirements address most areas of the gas operator activities. Detailed requirements apply to the materials that may be used for constructing new gas pipelines. The requirements also address permitted pressure levels for the systems, design standards for the facilities, construction requirements and initial testing of the facilities to ensure safety. There are extensive requirements for welding steel and other forms of joining materials. Corrosion control, operation and maintenance, emergency response and qualification of employees to perform safety-related activities are also covered. Gas employees performing safety tasks are also subjected to drug and alcohol testing requirements.

State and federal regulations mandate that LDCs maintain gas lines up to and including the gas meter. Maintenance BEYOND the gas meter, that is, the gas line that extends from the meter into your home is normally the responsibility of the gas user or property owner. See Are there gas pipes for which I am responsible?

Interstate Facilities
Primary jurisdiction for the safety of interstate pipelines – those that engage in commerce between States – rests with the United States Department of Transportation Pipeline and Hazardous Materials Safety Administration (PHMSA) Office of Pipeline Safety  (OPS).  In Connecticut, the Public Utilities Regulatory Authority acts as an agent for OPS and performs most inspections of the interstate pipelines for OPS. Ultimate enforcement authority rests with OPS.  The interstate facilities in Connecticut are Algonquin Gas Transmission, Iroquois Gas Transmission System, Tennessee Gas Pipeline – 3 pipeline companies - and Total Peaking Services, a liquefied natural gas facility. They are required to meet the Minimum Federal Safety Standards (49 CFR 191, 192, 193 and 199).

Hazardous Liquid Facilities
Jurisdiction for the safety of hazardous liquid pipelines rests with the PHMSA Office of Pipeline Safety (OPS).

PHMSA Operator Identification Numbers
A list of active and inactive PHMSA Operator Identification Numbers can be found at the National Pipeline Mapping System website.


The Public Utilities Regulatory Authority is an active member of the National Association of Regulatory Utility Commissions (NARUC). NARUC is a trade association representing the State public service commissioners who regulate essential utility services, such as electricity, gas, telecommunications, water, and transportation, throughout the country. As regulators, its members are charged with protecting the public and ensuring that rates charged by regulated utilities are fair, just, and reasonable.

The National Association of Pipeline Safety Representatives (NAPSR) is composed of state pipeline safety personnel who serve to promote pipeline safety in the United States and its territories. NAPSR supports the safe delivery of pipeline products by working closely with PHMSA, the industry and other interested organizations.

Gas Pipeline Safety

Content last updated March 2022