The Aliso Canyon Natural Gas Storage Facility (Aliso Canyon), located in the Santa Susana Mountains of Los Angeles County, is the largest natural gas storage facility in California. Southern California Gas Company (SoCalGas) crews discovered a leak at the natural gas storage well at Aliso Canyon on October 23, 2015. After several attempts, SoCalGas stopped the leak on February 12, 2016, sealing the well on February 15, 2016. It was later plugged and abandoned. More information on the well kill attempts can be found on the background on Aliso Canyon and actions to date.

On July 19, 2017, after inspection and analyses of all the wells at Aliso Canyon, we decided along with the California Geologic Energy Management Division (CalGEM, formerly known as the Department of Conservation’s Division of Oil, Gas, and Geothermal Resources, or DOGGR), that the facility was safe to operate, and it safe to operate. It was reopened at a reduced capacity. CalGEM, which has primary jurisdiction over Aliso Canyon’s underground facilities, decided the maximum allowable operating pressure in the field to be 2,926 psi, which translates to an inventory of 68.6 billion cubic feet (Bcf) of natural gas. This is a 17.4 Bcf reduction compared to Aliso Canyon’s pre-leak capacity of 86 Bcf. Read more information from CalGEM’s Aliso Canyon Storage Facility.

Following the direction provided by the legislature in California Public Utilities Code Section 715, we decided the inventory needed "to ensure safety and reliability for the region and just and reasonable rates in California.” We made this decision in the “715 Reports,” which are known more formally as the Aliso Canyon Working Gas Inventory, Production Capacity, Injection Capacity, and Well Availability for Reliability Reports. In its last 715 Report, updated on July 6, 2018, we capped Aliso Canyon’s maximum allowable inventory at 34 Bcf.

We also developed the Aliso Canyon Withdrawal Protocol, a protocol describing the process to be followed before making a withdrawal from the Aliso Canyon storage facility. The Withdrawal Protocol is developed with input from the California Energy Commission (CEC), the California Independent System Operator (CAISO), and the Los Angeles Department of Water and Power (LADWP), together known as “the Joint Agencies.”

We work closely with the Joint Agencies to monitor natural gas availability in Southern California, protect public safety, and make sure of energy reliability in the region. Since 2016, we have worked with the Joint Agencies to develop Summer and Winter Technical Assessments that assess energy reliability challenges in Southern California in the coming season. We also periodically create Southern California Conditions and Operations Reports that look back on various seasonal reliability events.

On our investigation webpage you can find information on the proceeding we opened on Feb. 9, 2017 (called an Order Instituting Investigation; I.17-02-002) to determine the feasibility of minimizing or eliminating the use of Aliso Canyon.

Find information about our actions and links to information available on other state agency websites, starting with the latest information.

Aliso Withdrawals

CPUC Reports

Useful Links & Documents

For more information, please contact

News and Outreach Office
California Public Utilities Commission
505 Van Ness Avenue
San Francisco, CA 94102

(415) 703-1366