PG&E employees installing gas lines

Gas Operations

Every day, PG&E works toward its goal to become the safest and most reliable provider of natural gas in the country. We have been conducting extensive safety testing, replacing and upgrading pipeline, and investing in advanced inspection, monitoring and control technologies. Though we have made progress, we have more to achieve. We are intent on building a 21st-century gas system that is stronger, safer and more durable than ever before.

Our Approach

As the owner and operator of one of the largest natural gas systems in the United States, PG&E is responsible for an integrated transmission, storage and distribution system that consists of approximately 42,800 miles of distribution pipeline (as well as additional mileage associated with connecting to individual gas services), 6,700 miles of backbone and local transmission pipeline, and various gas storage facilities. The system also includes eight natural gas compressor stations, which receive and move natural gas through our pipeline network.

Our focus remains on maintaining and operating this system safely and reliably, with public and employee safety as the single most significant driver of our work.

This approach has helped us achieve PAS 55-1: 2008 and ISO 55001: 2014 certifications for best-in-class asset management; become one of the first companies in the United States to meet the rigor of a new industry gold standard for pipeline safety and safety culture: the American Petroleum Institute Recommended Practice 1173 (API RP 1173); and become the first gas provider to meet the chemical industry’s RC14001® management system standard.

2015 Milestones

Gas Transmission System

PG&E has embarked on one of the most comprehensive gas transmission modernization programs in the United States, if not the most aggressive. Since 2011, PG&E has achieved the following results through 2015.

  • Validated safe operating pressure by strength-testing or locating strength-test records for more than 920 miles of gas pipeline.
  • Replaced more than 155 miles of gas transmission pipeline.
  • Automated 235 valves, enabling remote-control shutoff of gas in an emergency.
  • Retrofitted more than 560 miles of gas transmission lines to accommodate in-line inspection tools, or “smart pigs,” that are used to inspect the internal condition of pipelines.

Gas Distribution System

The safety and reliability of PG&E’s gas distribution system has been enhanced with improvements in leak response and repair, the deployment of new tools and technologies, and an overhaul of our approach to records and information management.

We expanded our use of the world’s most advanced leak detection instrument, Picarro Surveyor™, which is 1,000 times more sensitive than normal leak detection devices. Other highlights from 2015 include:

  • Reduced the backlog of minor non-hazardous workable leaks to an all-time low of 94—from about 12,200 in 2010.
  • Responded to gas odor reports in an average of 20 minutes, representing top decile performance in the nation.

PG&E is also improving the quality of, and access to, our gas distribution records with the use of a Geographical Information System (GIS). This tool is designed to map, reconcile and analyze data from events involving PG&E assets. It is being deployed in concert with specialized employee training on how to use the centralized system.

Embedding Public Safety into our Operating System

PG&E is one of the first gas and electric providers to begin explicitly incorporating public safety metrics and targets into its operational goals and plans. We believe that tracking and reporting on these measures is essential. Examples of our accomplishments include:

  • Became one of the first companies in the U.S. to meet the rigor of a new industry gold standard for pipeline safety and safety culture. The American Petroleum Institute Recommended Practice 1173 (APR RP 1173), which outlines specific best practices for safe and effective pipeline operations underpinned by a healthy safety culture, was developed to provide a best-in-class framework for organizations that operate hazardous liquids and gas pipelines in response to major industry incidents.
  • Installed 235 automatic and remote shut-off valves. This milestone completed another significant safety recommendation issued by the National Transportation Safety Board (NTSB) following the 2010 San Bruno accident. We have now satisfied 11 of the 12 safety recommendations made by the NTSB for improving the operations and management of our natural gas pipeline system.
  • Made significant progress to enhance the safe operation of our gas infrastructure. Since 2011, we have validated safe operating pressure by strength-testing or locating strength-test records for more than 920 miles of gas pipeline, replaced more than 155 miles of gas transmission pipeline, retrofitted more than 560 miles of gas transmission lines to accommodate in-line inspection tools and collected and digitized more than 4 million records related to our transmission pipeline system and more than 12 million pages of records related to our distribution system.
  • Broke ground on a state-of-the-art training facility. We began building a new training facility in Winters, California, which will provide teams with a best in-class training environment by teaching enhanced safety protocols and via the use of the latest technologies. The facility will also have a significant positive economic impact on the community and region through hotel, sales and property tax revenue.
  • Developed and implemented cutting-edge technology. PG&E deployed a number of new, innovative gas safety tools in 2015. Examples include testing the use of the NASA Jet Propulsion Lab’s methane sensor on handheld devices, as well as the use of drones for inspection of remote infrastructure and the use of radio frequency identification technology to locate subsurface assets. We also initiated phase one of a GIS tracking and traceability tool pilot project—technology that will provide gas construction crews with real-time access to detailed maps of our underground gas system.

Measuring Progress

PG&E’s contributes to peer-reviewed study

PG&E contributed to the findings of a comprehensive, peer-reviewed study published in Environmental Science & Technology, confirming that methane emissions from local natural gas systems have significantly decreased in the past 20 years, even as the system’s mileage has increased. Improvements made to the natural gas system are contributing to a reduction in greenhouse gas emissions nationwide.

In 2015, we achieved key milestones, completing the 10th and 11th of the 12 NTSB safety recommendations from its report on the San Bruno accident. The 12th and final NTSB safety recommendation, which includes strength-testing natural gas transmission lines, is in “open-acceptable” status, indicating that the NTSB regards PG&E’s progress as appropriate and acceptable. Our gas system progress is detailed in the table below.

Gas System Progress
2010 2015
Gas Odor Response Times
Average response time in minutes Footnote 1 33.3 20.3
Percent response within 60 minutes 94.4% 99.6%
SCADA Footnote 2 Visibility and Control Points
Transmission pressures and flows 1,300 2,480
Distribution pressures and flows 295 1,310
Leak Backlog
Open Grade 2 and 2+ leak indications Footnote 3 12,203 94
Dig-In Reduction
Excavation damage/1,000 excavation tickets 3.5 2.11
Gas Transmission
Miles of pipeline replaced 9 >155
Miles of pipeline hydrotested 0 >750
Automated valves installed 0 235
Percent of system with GPS centerline data Footnote 4 0% 100%
Gas Distribution
Miles of main replaced Footnote 5 27 >310
  • 1. 2015 data represents top decile in the country. Return to table
  • 2. Supervisory control and data acquisition. Return to table
  • 3. Grade 2 and 2+ leaks are minor and non-hazardous. Return to table
  • 4. GPS survey was completed for 100% of the accessible transmission pipeline system using highly precise mapping tools. Return to table
  • 5. In 2014, all known remaining cast-iron pipe was decommissioned. Return to table
PG&E workers with LNG/CNG trucks.

World’s largest sustainable portable LNG supports safety tests

To complete pipeline safety pressure tests in the Santa Cruz region, PG&E needed to take the area’s primary natural gas transmission line out of service for several weeks. PG&E was able to provide an alternate method of safe, uninterrupted gas service to 46,500 customers while testing was underway, using a portable liquefied natural gas/compressed natural gas (LNG/CNG) support program unparalleled in scope. Over the course of the project, PG&E safely injected more than 3.5 million pounds of LNG into the system so that safety pressure tests could be conducted in the area.

Photo by Chris Biedeman

Looking Ahead

PG&E expands greenhouse gas reduction commitment by joining EPA’s Methane Challenge

PG&E furthered its commitment to reduce greenhouse gas emissions by joining the U.S. Environmental Protection Agency’s Natural Gas Methane Challenge as a founding partner, joining with 40 other U.S. companies. This voluntary program, aimed at reducing emissions from the oil and gas industry, aligns with PG&E’s goals to deliver safe, reliable and clean energy resources to its customers.

PG&E continues to make progress toward becoming one of the safest and most reliable gas providers in the country. The California Public Utilities Commission approved a comprehensive scope of work through 2017 to:

  • Replace vintage pipelines that could be at risk from land movements
  • Continue testing pipelines to verify safe operating pressures
  • Continue controlling corrosion to avoid underground leaks
  • Install more automated and remotely operated safety valves to quickly turn off gas in case of an emergency
  • Inspect the interior of more pipelines to detect and repair hidden flaws
  • Strengthen levee and water crossings
  • Maintain underground gas storage facilities that help meet demand on cold days
  • Modernize infrastructure control systems, databases and risk analysis programs

We also continue our work to maintain our gas safety excellence status, including API RP 1173. Lloyd’s Register will also return for an audit of our certifications under International Organization for Standardization (ISO) 55001: 2014 and Publicly Available Specification (PAS) 55-1: 2008. PG&E is one of the first companies in the world to hold both best-in-class gas system operator certifications. In 2017, PG&E’s gas operations will undergo a full recertification of the asset management system against PAS 55/ISO 55001 standard requirements.

PG&E also became the first gas provider to meet the chemical industry’s RC14001® management system standard. PG&E successfully passed a comprehensive gas safety audit reviewing numerous end-to-end safety processes to achieve certification to RC14001. This standard was issued through the American Chemistry Council for process safety; community communications; product safety; and occupational safety, health, environmental and security practices against which organizations can be evaluated and certified by a third party. The standard embodies the industry’s Responsible Care® Guiding Principles.





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