California’s Methane Leak Doubled the Emission Rate of Los Angeles

By Janine Anderson | February 25, 2016 1:00 pm

The Aliso Canyon natural gas storage facility shot from UC Davis scientist Stephen Conley’s airplane. (Credit: Stephen Conley/UC Davis)

When a well tapping into the country’s fourth-largest natural gas storage facility blew out in October, gas started leaking. No one knew how much of the powerful greenhouse gas was flowing out, we could only estimate.

The California Energy Commission already had someone under contract who could tell them, and within two weeks, Stephen Conley had stopped monitoring pipelines and was instead strapped into an airplane measuring the plume of gas wafting over the densely populated San Fernando Valley.

Conley, a University of California-Davis researcher and president of Scientific Aviation, flew a fixed-wing, single-engine Mooney aircraft, armed with wind sensors and chemical analyzers. He waited until a northerly wind blew the plume over the flat, populated valley. Then, starting at an altitude of 200 feet, he flew back and forth, perpendicular to the wind, climbing slightly in altitude each time, until he rose above the plume.


Stephen Conley flies towards the Aliso Canyon Natural Gas Storage Facility leak on Jan. 8. (Credit: Joe Proudman / UC Davis)

“This is exquisitely difficult flying,” says Thomas Ryerson, a National Oceanic and Atmospheric Administration research chemist. “They’re just getting completely beat up. Anyone who flew got really badly airsick.”

But they kept making the trips.

Inspecting the Plume

“This is one of the most well-studied leaks in the U.S.,” says Ryerson.

Ryerson, Conley and their research team have released a paper on the sheer scale of the plume, published Thursday in the journal Science. Using data from 13 passes through the plume, they have built a calibration system for when the next leak occurs, which will help quantify the methane output from cities, pipelines and animals. Their findings also put the leak into perspective.

The 112-day leak at the Aliso Canyon gas storage facility released more than 97,000 metric tons of methane through the seven attempts to close it. Enough gas was leaking on a daily basis to fill a balloon the size of the Rose Bowl — a stadium that can seat over 92,000 spectators. It temporarily created the largest known human-caused source of methane in the United States, and the Southern California Gas Company paid more than 1,600 households to temporarily relocate during repairs.

At its peak, the gas leak effectively doubled the methane emission rate from all sources in the entire Los Angeles Basin.

“The Aliso leak all went right into the atmosphere,” says Ryerson. “It was the equivalent of over a half-million cars on the road for a full year.”

Conley, flying in a pollution-detecting airplane, provided the first estimates of methane emissions spewing from the Southern California leak. (Credit: Joe Proudman/UC Davis)

Conley flew in a pollution-detecting airplane to compile the first estimates of methane emissions spewing from the Southern California leak. Here, he flies near the gas storage facility on Jan. 8. (Credit: Joe Proudman/UC Davis)

The leak was closed on Feb. 11, but they continue to go back. They are now measuring residual leakage from the canyon and the dozens of wells in the area. The data they’ve been able to gather — and that they’re still gathering  — will help develop better tools to measure future leaks.

Preparing for the Next Leak

Ryerson said access to this kind of monitoring equipment is incredibly important. A large leak in the North Sea in 2012 was under control two months earlier than expected because they had access to a monitoring aircraft, he said. Planes also helped build a better understanding of what was happening a mile below the ocean’s surface in the Deepwater Horizon leak.

Ryerson said he can probably count on one hand the number of aircraft equipped to do this kind of analysis.

“They’re often off doing something else,” he said.

Conley called this situation a “lucky break” because CEC had already contracted his company.

“We still missed the first two weeks,” he said. “That’s one of our take-home lessons. As a nation, we need a process in place where we can have an aircraft on site within hours, not weeks.”

Ryerson agreed.

“Let’s do the next one better,” he said.

CATEGORIZED UNDER: Environment, top posts
  • Uncle Al

    What heinous EPA and Enviro-whiner penalties were levied? None at all.
    What heinous civil and criminal penalties were levied? We’re waiting.
    Targeting citizens is OK because they cannot bite back.

    • OWilson

      Forget building rocket ships and thriving economies.

      The gig is now inspecting and monitoring what everybody else is doing, and making a big deal about it. You need to be a devout cool aide drinker though., No skeptics allowed :)

      Or riding those luxury yachts in the South Seas with your youthful friends, lots of champagne and memorable sun down beach parties, reporting on how the world is destroying the ecosystem, between parties. All expenses paid.

      In my steel town Sheffield, where I grew up, they used to say “where there’s muck, there’s money”.

      Now like in Detroit, no muck, but also no money :)

      • Uncle Al

        Women view their homes as their bodies, men view their habitations as their workbenches. The former demand curtains, the latter clean up after making something. Feminize the world!

        • OWilson

          Our feminized men, who were taught to “get in touch with their feminine side” cannot figure out why their women run off with the macho bad guys :)

          • CB

            “Our feminized men…”

            Okay, stop.

            You don’t own Men. You don’t own Women.

            That’s illegal.

            Now how might the “feminine” or “masculine” nature of anyone change the effect of methane on planetary temperature?

            “Molecule per molecule, methane is 22 times more potent as a greenhouse gas than carbon dioxide on a 100-year timescale, and 105 times more potent on a 20-year timescale”

            (NASA, “Is a Sleeping Climate Giant Stirring in the Arctic?”)

          • Mike Richardson

            Don’t you understand? It’s all interconnected — feminism, emasculation, and belief that methane is a greenhouse gas — women are preventing their men from passing gas, and it emasculates them! But seriously, you see how tangential it gets from a topic that shouldn’t be controversial, like leaking huge amounts of methane into the atmosphere is a bad thing. I think it’s an avoidance mechanism, actually.

          • OWilson

            Your country (and all major Western societies) was built by industry, coal miners, steel makers, road and railmakers, fabricators, and other men who were not afraid to work in a little dust and smoke.

            Now you get all your manufactured products from the third world, because you can buy them with your unsustainable and ever growing national debt, which you pass along to future generation when the bills become due long after you are dead.

            You don’t really, really care who or how they manufacture your household appliances as long as they are cheap.

            All without getting your well manicured delicate hands dirty :)

            Time to regulate those leaky, cheap ball point pens :)

          • CB

            “folks like me put everything on record”

            Everything except for a coherent reply…

            Mr. Wilson, how might ball point pens change the fact that methane warms the planet?

            “Methane (CH₄) is the second most prevalent greenhouse gas emitted in the United States from human activities.”

            (US EPA, “Overview of Greenhouse Gases”)

          • OWilson

            Ball pens leak, cars leak, trains and planes crash, ships sink, dams burst, space shuttles explode, wells blow out. Accidents happen.

            All a part of the ascent of civilized modern man.

            Then you have fined and disbarred serial sexual molesters and congenital liars who continually “lose” their records, ready to buy their way back into your White House, and your IRS Director who was determined to make it happen, Pleads The Fifth with impunity. Drives are “wiped”, hard drives destroyed, back ups “fail”, and bathroom servers are used for the nations secure business.

            All a part of the regression to Banana Republic.

            Let’s have some common sense perspective on “outrage”?

          • CB

            “Ball pens leak, cars leak, trains and planes crash, ships sink, dams burst, space shuttles explode, and yes, gas wells blow out. Accidents happen.”

            Yup… and does any of that yammer change the effect of methane on planetary temperature?

            “CH₄ is ~20 times more potent than CO₂ as a GHG”

            (Nature, “Methane Hydrates and Contemporary Climate Change”)

          • Mike Richardson

            Yep, we had a blow out five years back offshore. Worst oil spill in history, and the north central Gulf of Mexico still hasn’t made a full recovery. Marine life devastated, and countless fishermen put out of business, not to mention the long-term health effects on those involved in the clean up. So accidents do happen in any industry, but the oil and gas industry produces some of the most severe consequences when things go bad. There may be trade-offs with moving to renewables, but nothing compares to the side effects of the world’s fossil fuel addiction.

          • OWilson

            As long as you have a dwelling, a computer, modern household appliances and don’t walk to work, you will need fossil fuels, look in the mirror.

            That’s YOU :)

            There have been worse environmental accident cleaned up (see top ten spills).

            If they can be catching fish today in the infamous fire hazard Chicago River, the Thames, and my personal carcogenic cesspool the River Don, we can do more than you think.

          • Mike Richardson

            Contrary to what you say, we won’t need them forever, and will be rid of them sooner rather than later. You can minimize the cost in lives and the environment all you want, but the fossil fuel industry is well aware of that cost, and has done everything in its power to make sure it bears as little of it as possible. They really don’t need cheerleaders like you, as long as they can make obscene profits at the public expense.

          • OWilson

            Don’t worry.

            You’ll soon have a new POTUS, and I’m sure she’ll be put an end to your “obscene profits”.

            All you have to do is believe, like last time :)

          • Mike Richardson

            Seems to work for you, at least with regards to believing in a worldview that rejects science if it runs counter to your political dogma. I suppose I should take advice from an expert. 😉

          • OWilson

            Science, good!

            Politics, not so good.

            Low info folks don’t know the difference :)

          • Mike Richardson

            You sure don’t! 😉

          • OWilson


  • Mike Richardson

    More industry negligence, this time with methane. About par for the course when dealing with these companies.

    • OWilson

      Looks like the C.E.C. were happy to hire “these companies”, the aviation industry, and a private specialty aircraft monitoring company, to evaluate the accidental spill.

      Try doing that with windmills and solar panels. :)

      • Mike Richardson

        Lol… you wouldn’t need to monitor an environmental disaster from a power source that doesn’t cause one. Epic fail.

        • OWilson

          “Environmental disasters” to be monitored come in many forms, hurricanes, volcanoes, floods and earthquakes, but we know in your world, only humans spread death and destruction.

          How telling, and sad!

          • Mike Richardson

            We were discussing specifically man-made environmental disasters, the type you always minimize. Which itself is rather telling, and sad.

          • OWilson

            Glad to see you at least acknowledge the other 99.9% of “environmental disasters” that come to us courtesy of Mother Nature herself :)


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