The Federal Energy Regulatory Commission accepted California Independent System Operator Corporation’s request for a one-year extension of market rule changes to manage natural gas constraints posed by limited operability of the Aliso Canyon storage facility following a major gas leak in October 2015, according to a Nov. 26 order. The facility, operated by Southern California Gas Company, has been partially restored since the leak, but the region continues to face supply shortages due to limitations on withdrawals, pipeline outages, and declines in inventory. For the 2018-2019 winter, the grid operator expects gas system capacity conditions to be virtually unchanged compared to the prior winter, but anticipates minimum generation requirements to be higher. After the leak, the total capacity in the company’s service territory dropped by nearly half from 136 billion cubic feet to 74 billion cubic feet, according to a June report from the Energy Information Administration. The commission approved six of the seven rule changes to remain in place until Dec. 31, 2019. FERC authorized the revisions in June 2016 to provide the grid operator with a set of tools on a temporary basis to address the reliability and market distortion risks posed by the constraints, and subsequently allowed one-year extensions.