After nearly four days of being asked to lay off the heat during a cold spell, SoCal Gas customers were told Thursday they could go back to business as usual.
Southern California Gas Co. lifted its gas advisory for both residential and business customers as of 1 p.m. Thursday. During a gas advisory, customers are asked to limit their use of major gas appliances and keep the thermostat, when set to heat, at 68 degrees or lower.
The advisory was called at 7 a.m. Monday as demand crept up because of the cold weather. SoCal Gas said that withdrawals from the Aliso Canyon storage field — over the objections of local residents — played a critical role in meeting the increased demand.
Aliso Canyon was shut down following a months-long leak that forced residents of nearby Porter Ranch from their homes. The leak depleted the field to 15 billion cubic feet of gas storage, which is about what customers in Los Angeles and Orange counties would use over three to four days of peak demand.
How much gas was withdrawn?
On Tuesday, SoCal Gas withdrew about 30 million cubic feet of natural gas between 7:25 a.m. and 10:50 a.m., according to the utility. On Wednesday, another 20 million cubic feet were withdrawn between 7 a.m. and 9 a.m.
To put that in perspective, the total amount delivered to customers on Monday and Tuesday was 4.1 billion cubic feet. SoCal Gas said that was the highest demand so far this winter.
Aliso Canyon still has about 14.8 billion cubic feet of natural gas in reserve.
Why was it needed?
Some residents have expressed concern over the withdrawal and criticized the company for using what they call a “manufactured shortage” to pressure officials into lifting a moratorium on using the gas stored at the field.
SoCal Gas said it maxed out its withdrawals from other storage fields before tapping Aliso Canyon. It takes three to four hours for gas traveling through interstate pipelines to reach customers in the L.A. Basin, so sudden spikes in usage can make it difficult to meet demand, the utility said.
On Tuesday and Wednesday, the hourly customer demand outstripped what the company could deliver through those pipes, as Southern Californians weathered low overnight temperatures — low enough to trigger hard freeze warnings Thursday.