When the massive methane gas leak in Aliso Canyon was discovered in California last year, it was quickly projected to be the largest gas leak in U.S. history. Now, a week after the failed well was plugged, new research finds that’s exactly the case.
Through the 112-day leak, the Aliso Canyon Storage Facility — located about 30 miles northwest of downtown Los Angeles — released 97,100 metric tons of methane, creating the largest known human-caused source of methane in the country, according to the study published Thursday in the journal Science. It also doubled the leak rate of all other methane sources in the Los Angeles Basin combined.
At its peak, the leak rate exceeded that of the next largest point source of methane in the U.S. — an underground coal mine in Alabama — by a factor of two, and it was comparable to total emission rates of entire oil and gas production regions in the country. “Aliso Canyon will be, certainly, the biggest single source of the year,” said co-lead author Stephen Conley, a researcher at the University of California Davis and Scientific Aviation, to the Los Angeles Times. “It’s definitely a monster.”
The study establishes the full extent and damage of an unprecedented leak that sickened Los Angeles, prompted the evacuation of 6,000 people and sparked myriad lawsuits. It also raised serious problems for the regional environment, since methane is a greenhouse gas 86 times more potent than carbon dioxide over a 20-year period.
Protestors wearing gas masks, attend a hearing over a gas leak at the southern California Gas Company’s Aliso Canyon Storage Facility near the Porter Ranch section of Los Angeles. Scientists say a gas leak that forced thousands of people from their Los Angeles homes was the largest reported release of climate-changing methane in U.S. history.