In selected parts of the Greater Los Angeles area in Southern California, the Environmental Defense Fund (EDF) and Google's Earth Outreach unit are turning up numerous methane leaks and pinpointing the locations for Sempra Energy's Southern California Gas Co. (SoCalGas).

SoCalGas on Thursday asked state regulators to approve additional ratepayer funding for the program that encompasses the leak-detection effort.

EDF-Google applied the same technology that SoCalGas and other utilities have been perfecting, but it only is the first step in further boots-on-the-ground surveying by SoCalGas to determine which leaks represent safety hazards and must be fixed.

Developed as part of an EDF-Google technology partnership, a set of interactive online maps was created for the Los Angeles suburbs of Chino, Inglewood and Pasadena, supposedly identifying the size and location of nearly 250 leaks, all subsequently reported to SoCalGas and none of them representing an unsafe situation, according to a Los Angeles-based SoCalGas spokesperson.

Noting that it has been participating in EDF's methane mapping project, applying a top-down methodology using car-mounted sensors sampling air, SoCalGas filed with the California Public Utilities Commission (CPUC) Thursday to accelerate its pipeline replacement and leak repair program. If approved, it expects to repair all of the currently identified nonhazardous leaks on its transmission and distribution pipeline system.

Last year, EDF-Google unveiled plans for a pilot project that would map natural gas pipeline leaks beneath the streets of Boston, Indianapolis and Staten Island in New York City (see Daily GPI, July 16, 2014). Meanwhile, state regulators (including the CPUC) and industry associations have jump-started programs to improve monitoring, detection and plugging of methane leaks (see Daily GPI, March 20).

"New technologies like this that enable rapid detection and measurement make it easier for utilities like SoCalGas to find leaks, prioritize repairs, and maintain the overall integrity of their pipes," said EDF's Tim O'Connor, director of the group's California climate initiative. Echoing government and industry officials, O'Connor called methane leaks "a serious climate problem, and a major issue throughout the gas supply chain."

According to EDF, the maps were developed using specially equipped Google Street View mapping cars, using a partnership with Google Earth Outreach. This Google unit is dedicated to showcasing new environmental sensing technologies that are available online ( SoCalGas on Thursday unveiled an interactive map on its website ( that allows the general public to view methane indications and nonhazardous gas leaks located near its pipeline system.

"Leaks like these usually don't pose an immediate safety threat," an EDF spokesperson said. "But leaking natural gas -- which is mostly methane -- has a powerful effect on the climate, packing 84 times the warming effect of carbon dioxide [CO] over a 20-year time frame."

The SoCalGas spokesperson said that while the utility supports the EDF-Google program objective of cutting methane emissions, "it is important to note that the emission points on these maps are not safety hazards."

SoCalGas has a program for identifying, assessing and repairing gas leaks in its pipeline system that pose safety concerns, the spokesperson said. "We already use similar technology to what was used in the EDF mapping project and have a very good program for managing leaks that develop on our system."

EDF and Google are not analyzing and determining what to do with the methane data. SoCalGas said the measured methane levels in ambient air may be coming from natural sources, since all of Southern California has underground oil/gas deposits, and the reading could be coming from landfills, dairies and other non-gas infrastructure sources.

"SoCalGas also does similar ambient measures, in this case using the very same technology used by EDF, but we must go beyond mere methane detection," the spokesperson said. "After we receive ambient readings, we go out into the field, perform leak surveys by walking the system to do bottom-up detection, actually finding leaks and then scheduling them to be monitored and fixed based on their severity."

In about half the instances (40-50%) there is no correlations between ambient methane detected an actual system leak, the SoCalGas spokesperson said.

EDF cites the California Air Resources Board's latest data showing that oil/gas operations of all kinds in the state emitted roughly 140,000 metric tons of methane in 2012, but industry and other government sources have cautioned that statistics and data-gathering methods for measuring macro methane leaks throughout the nation are ill-defined and still being perfected. Last year, the Interstate Natural Gas Association of America committed to building on the industry’s leak detection advances by developing guidelines that enhance efforts to discover and repair leaks from pipelines and associated equipment (see Daily GPI, July 29, 2014).

EDF characterized the new online Google maps as the first detailed public data on leak sizes in Southern California (before SoCalGas' new online map), adding that utilities like SoCalGas are now required to report the number and locations of leaks they detect on their systems to state regulators, but they are not required to measure them.

"It is not clear how or when that data will be publicly available as required by law," the EDF spokesperson said.

In urging more action from state and local policymakers, O'Connor said, "aging pipes can lead to more leaks and are a growing challenge in many parts of the country. It's time to start solving this problem, and we're very confident [policymakers] can do it."