Southern California Gas Co. tapped the troubled Aliso Canyon natural gas storage field Tuesday after issuing an alert about potential supply shortages because of increased consumer demand.

Hours after withdrawing gas from Aliso Canyon — a facility that has been shut down since it experienced the worst methane leak in U.S. history in fall 2015 — the utility stopped using the facility because demand declined, although warnings about shortages of natural gas remained in effect.

“Cold weather is expected in the greater Los Angeles region tonight and into tomorrow, which could impact demand for natural gas,” the company said in a statement. “Additionally, low temperatures forecasted east of California for this week could impact the availability of natural gas supply to the Southern California region.”

But some questioned the safety of pulling gas from the storage field, the first such withdrawal since January 2016, and accused Southern California Gas of manipulating the natural gas supply to make the case for reopening the storage field ahead of hearings on the matter next week.


“Reopening Aliso, even on a limited basis, is inadvisable given the fact that we cannot determine that the facility is safe without first knowing what caused the biggest methane gas blowout in U.S. history,” advocacy groups Food & Water Watch and Consumer Watchdog stated in a letter Tuesday to state Atty. Gen. Xavier Becerra.

The groups called on Becerra to investigate possible manipulation of the gas supply by Southern California Gas, a subsidiary of San Diego-based Sempra Energy.

San Diego engineer Bill Powers, who testifies as an expert before state regulators, said utility data show that Southern California Gas had decreased the amount of natural gas it was buying even as cooler temperatures settled in on the Los Angeles area. Then, Powers noted, the utility began withdrawing gas from Aliso Canyon.

“I’ve been projecting for two weeks that they’ve been looking for a chance to withdraw gas from Aliso Canyon,” said Powers, who was among those who signed the letter to Becerra.


Rodger Schwecke, Southern California Gas vice president of gas transmission and storage, said utility managers decided to withdraw gas from Aliso Canyon and other storage fields because of a “pipeline constraint.”

“In this case, [natural gas supplier] Kinder Morgan reduced delivery,” Schwecke said.

But when questioned by the Los Angeles Times, Kinder Morgan said it was delivering natural gas as scheduled.

“There are currently no delivery issues from Kern into the Mojave pipeline system, which delivers natural gas to SoCal,” said Sara Hughes, a spokeswoman for Kinder Morgan.


In response to Kinder Morgan’s assertion that deliveries were made as scheduled to Southern California Gas, the utility reiterated that deliveries “were reduced” Tuesday compared with Monday deliveries.

Tuesday’s allegations about natural gas manipulation aren’t the first such claims lodged against the utility. Sempra agreed to pay $375 million as part of a settlement over allegations that it conspired to restrict natural gas supplies and raise prices during the state’s energy crisis of 2000-01. Sempra agreed to the payment but admitted no wrongdoing.

Gov. Jerry Brown ordered an moratorium on injections of gas into the Aliso Canyon storage field after the leak that began in October 2015 forced the utility to release much of the facility’s supply. Withdrawals of natural gas are allowed from the underground sandstone and shale formations.

The well’s blowout caused 8,000 residents, largely in the nearby Porter Ranch community, to flee their homes. The residents complained of headaches, nosebleeds and nausea. The gas leak kept some out of their homes for months.


Inspectors have been examining the storage field’s wells for safety, but the majority of residents have been pressing to keep the storage field closed for good. Investigators hired by the state have yet to determine what caused the pressurized well to rupture.

State regulators last week announced that Aliso Canyon is safe to reopen at a third of its original size. Public hearings on reopening the facility are scheduled for Feb. 1 and 2 in Woodland Hills. A state Senate committee will hold a hearing on energy matters Tuesday, and Aliso Canyon is expected to be discussed.

Last summer, state regulators and the utility stated in reports that without Aliso Canyon — the state’s largest natural gas storage field and the fourth-largest in the nation — Southern California Gas might lack the ability to meet energy demand.

The ominous reports said that without Aliso Canyon, Southern California could face as many as 14 days of blackouts during the summer and pilot lights at residential homes could go dark in the winter. Questions immediately surfaced about the reports’ methodology, and some critics accused the utility of using scare tactics to hold on to Aliso Canyon.


Regulators, utilities and energy providers have been working on alternatives such as battery storage to supplement the loss of Aliso Canyon.

Still, Southern California Gas argues that it cannot meet natural gas demand without the storage field. In addition to providing backup supply, the field enables the company to buy gas when prices are lower and use the storage field for supply when market prices run high.

But this week, natural gas prices were down more than 3%, according to the U.S. Energy Information Administration, when Southern California Gas reduced the amount of gas from suppliers and increased the amount used from storage.

On Sunday, the utility began issuing warnings to customers to conserve energy as cooler temperatures could strain natural gas supplies. The utility has issued similar warnings over the course of the winter.


But the summer blackouts never occurred and so far, pilot lights have remained on, even as a warming trend is expected in the coming days.

ivan.penn@latimes.com

For more energy news, follow Ivan Penn on Twitter: @ivanlpenn

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