Big benefits from replacing leaky natural gas pipelines – Stanford study

Methane leaks mostly caused by ancient natural gas distribution cast-iron pipes, some over 125 years old

A new study from Stanford University claims the benefits of replacing old, leaky natural gas distribution pipelines far outweigh the costs.

Much of America’s natural gas pipeline distribution system is old and leaking.

Pipeline replacement programs in cities can cut natural gas leaks by 90 per cent, according to Rob Jackson, the Michelle and Kevin Douglas Provostial Professor at Stanford.

“The surprise wasn’t that replacement programs worked,” Jackson told the Stanford Report.  “It was that they worked so well.”

Thee study examined the replacement of pipelines made of cast iron and other outdated materials in the cities of Durham, North Carolina and Cincinnati, Ohio, and Manhattan Island in New York City.

“We identified 132, 351 and 1,050 leaks in Durham, Cincinnati and Manhattan, respectively, across 595, 750 and 247 road miles driven,” the study said, as reported by Platts.

The team drove cars equipped with sensitive methane-mapping instruments across 1,600 road miles of Manhattan, NY; Cincinnati, Ohio; and Durham, NC.

Rob Jackson, the Michelle and Kevin Douglas Provostial Professor at Stanford.

They discovered that some cities have more leaks than others.  And some neighborhoods have far more leaks than others.

For instance, Jackson and his team discovered only one-tenth the number of leaks per mile in Durham and Cincinnati – where public-private partnerships have replaced outdated pipelines – than in Manhattan or in Boston and Washington, D.C., two cities the team had previously mapped, according to the Stanford Report.

Jackson says the best predictor of leaks was the presence of old cast-iron piping and unprotected steel pipes, much of which is over 70 years old and, in some cases, dates back to the 19th century.

“It’s not just U.S. cities,” Jackson told The Report. “There are many cities in Europe and elsewhere with old, unprotected piping. We need smart financial incentives to upgrade our oldest pipelines. It’s time to get them out of the ground.”

The likelihood of leaks was similar in Boston, Manhattan and Washington, D.C., around 4.3 leaks per mile. But in Durham and Cincinnati the research team measured only 0.22 and 0.47 leaks per mile, respectively.

“Emissions during the production, processing, storage, transmission and distribution of oil and gas were the second largest anthropogenic source of methane to the atmosphere globally in 2013,” according to the study, which says that methane’s global warming potential is 87 times greater than that of carbon dioxide over 20 years and 36 times larger over 100 years.