Pipeline Safety:

Department of Transportation Needs to Complete Regulatory, Data, and Guidance Efforts

GAO-15-843T: Published: Sep 29, 2015. Publicly Released: Sep 29, 2015.

Additional Materials:


Susan Fleming
(202) 512-2834


Office of Public Affairs
(202) 512-4800

What GAO Found

The Department of Transportation's (DOT) Pipeline and Hazardous Materials Safety Administration (PHMSA) has begun but not completed efforts to improve pipeline safety in response to GAO's prior recommendations:

Gathering pipelines : In 2012, GAO found that while gathering pipelines that are not regulated by PHMSA were generally considered to present less safety risk than other pipelines, PHMSA did not collect comprehensive data to identify such risks. GAO concluded that such data could help pipeline safety officials and pipeline operators increase the safety of these pipelines by better identifying and quantifying safety risks. In 2014, GAO found that construction of larger, higher-pressure gathering pipelines had increased due to the increased production of oil and gas, raising safety concerns because an incident could affect a greater area than an incident from a smaller, lower-pressure pipeline. PHMSA plans to issue proposed rules in fall 2015 that include collecting data on unregulated gathering pipelines.

Pipeline operator incident response : In January 2013, GAO found that PHMSA's data on operators' incident response times were not reliable, limiting the agency's ability to move to a performance-based approach for incident response. Improved data would allow PHMSA to determine appropriate response times for different types of pipelines, based on location and other factors. PHMSA plans to require changes in operator reporting to improve its incident response data and develop a performance-based standard as part of an upcoming rulemaking.

Gas pipeline assessment : In June 2013, GAO found that a requirement for gas transmission pipeline operators to reassess the integrity of their pipelines every 7 years provided a safeguard that issues were regularly addressed, but was not fully consistent with risk-based practices. A risk-based approach based on individual pipeline characteristics could call for assessments to occur more or less frequently than 7 years. However, implementing intervals longer than 7 years could require additional inspection resources to verify that operators appropriately assessed risk. GAO also found that guidance for calculating assessment intervals was lacking. PHMSA plans to issue guidance in 2016 and is researching the feasibility of risk-based assessments occurring less frequently than every 7 years.


Pipeline System


Why GAO Did This Study

The nation relies on a pipeline network of more than 2.6 million miles to transport hazardous liquids and natural gas. This network includes gathering pipelines that transport products to processing facilities and transmission pipelines that transport products from processing facilities to users (see figure). Pipeline safety oversight from PHMSA, along with state partners, covers issues such as incident response planning and integrity management. PHMSA uses a risk-based approach to regulate pipelines, resulting in regulation of all transmission pipelines and about 10 percent of gathering pipelines. Specifically, PHMSA does not regulate gathering pipelines that are smaller, operate at lower pressure, and are located in rural areas.

This statement addresses PHMSA's efforts in the areas of (1) gathering pipeline safety, (2) pipeline operator incident response, and (3) assessment of natural gas pipeline integrity. It is based on GAO's March 2012, January 2013, June 2013, and August 2014 reports on pipeline safety and July 2015 updates from PHMSA on its actions to respond to the reports' recommendations.

What GAO Recommends

In its reports, GAO made seven recommendations to DOT to improve pipeline safety data and guidance and to move forward with proposed rulemaking to address safety risks. GAO recommended, for example, that DOT move forward with proposed rulemaking to address risks from newer gathering pipelines. DOT is taking actions to respond to the recommendations.

For more information, contact Susan Fleming at (202) 512-2834 or flemings@gao.gov.

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