News Release News Release The City of Palo Alto
Communications Department
250 Hamilton Ave
Palo Alto, CA 94301


PRESS RELEASE 09/20/2010
Subject :

City Requests Confirmation from PG&E of Natural Gas Transmission Line Locations and Operation Practices in Palo Alto
Contact : James Keene, City Manager    650-329-2563

Palo Alto, CA – The City of Palo Alto has significant information related to the location of PG&E transmission lines sited within Palo Alto. However, the City wants to ensure that it has the most up-to-date information. The City Manager has sent a letter to the President of PG&E to request accurate pipeline information.

In light of the tragic events in San Bruno September 9th, communities along the Peninsula are extremely concerned about the location and condition of PG&E’s high pressure natural gas transmission lines, especially those located in densely populated areas. Palo Alto shares those concerns,” said James Keene, City Manager. “I have sent a letter ( to the President of Pacific Gas and Electric Company seeking accurate and updated information on the location and operation of PG&E’s facilities within the City of Palo Alto as well as how much risk the City of Palo Alto is susceptible to if there is any failure of PG&E’s facilities within the city.”

On behalf of the Palo Alto community, City Manager Keene has requested in a letter that PG&E provide accurate transmission line locations and updated information on the condition of the PG&E natural gas facilities in Palo Alto, including:

  • Confirmation of the location of PG&E gas transmission lines;
  • Whether there are any high risk (related to public safety) PG&E gas transmission facilities located in Palo Alto and where they are;
  • Whether there are any high risk (related to public safety) PG&E gas transmission facilities located in Palo Alto and where they are;
  • Age of the facilities;
  • Size of the pipelines;
  • Pressure at which PG&E typically operates the facilities;
  • Whether the operating pressure has been reduced by PG&E recently;
  • Current operating pressure;
  • Scope and date of PG&E’s most recent pipeline maintenance activities;
  • Frequency and nature of maintenance activities for all of PG&E natural gas facilities located within the City of Palo Alto. 

“After comparing the pipeline maps available online to the public at, with what we know, we believe those maps are outdated and inaccurate,” said Valerie Fong, Director of Utilities. “We would like confirmation from PG&E that our information is correct.”

Palo Alto owns and operates its own natural gas distribution system and receives natural gas from PG&E’s transmission stations at four points of interconnection. Palo Alto distributes the gas to its residents and business customers. Both PG&E and the City of Palo Alto have gas pipelines within the city, however, the City’s facilities are very different from PG&E’s facilities. 

City-owned gas pipes are smaller distribution level pipes ranging in size from 2 inches to 12 inches, as compared to PG&E’s transmission pipes which are typically 24 inches or larger.  The City operates the distribution system at 25 pounds of pressure per square inch or less, with the exception of a dedicated service to one customer which is at 40 pounds of pressure per square inch. City utility crews understand that PG&E’s gas transmission system is typically operated from 100 to 400 pounds per square inch.

In order to ensure the integrity of the City’s gas system, the City surveyed the entire system for leaks last year in one year’s time, in an accelerated effort, rather than the five-year timeframe that is required. Because the City operates a gas distribution system, we, are often able to identify leaks on PG&E’s facilities in the course of our surveys and report such leaks immediately to PG&E. PG&E responds quickly to calls about leaks.

The City also ensures all workers who work on the City’s facilities are qualified to do so, and the City implements an aggressive gas main replacement program to ensure the integrity of the system. The result is that there is no current backlog of gas mains operating beyond their reasonable service lives. Additionally, and as part of the current maintenance schedule developed through the last two budget cycles, the City will be upgrading all four of the gas receiving stations that connect the City’s system with PG&E. The upgrade involves a re-build of the pressure regulating system. The project is on track as planned prior to the recent explosion in San Bruno, and will be open for bid by the end of this calendar year.  Work on the re-build is anticipated to begin in May 2011, following the end of the winter heating season, and will be completed in October 2011, prior to the start of the next winter heating season.

For more information about gas pipeline safety in Palo Alto, visit the City’s website at

A PG&E representative called City Manager James Keene today to notify him that the “Top 100” list, part of the utility’s ongoing risk management program used to prioritize engineering analyses and future work on its transmission pipelines, has been publicly released and posted on the PG&E website at In a follow-up email, the PG&E representative wrote that “the ‘Top 100’ list is part of our ongoing Risk Management Program...”[but]”...isn’t a list of projects PG&E has identified as priority candidates for replacement or upgrade for reasons of public safety.” In the Top 100 list, according to PG&E, there are no City of Palo Alto projects; however, there is a project at Stanford.

“We are appreciative of the information in the Top 100 list,” Keene said. “But we need to definitely know if any public safety risks exist in the pipeline sections in Palo Alto.”

Citizens may also call PG&E’s hotline at 1-888-743-7431 to learn more about whether their home or business is located near a high pressure transmission line.