Beneath Cities, a Decaying Tangle of Gas Pipes
March 23, 2014. Patrick McGeehan et al. New York Times
It is a danger hidden beneath the streets of New York City, unseen and rarely noticed: 6,302 miles of pipes transporting natural gas.
Leaks, like the one that is believed to have led to the explosion that killed eight people in East Harlem this month, are startlingly common, numbering in the thousands every year, federal records show.
The chief culprit, according to experts, is the perilous state of New York City’s underground network, one of the oldest in the country and a glaring example of America’s crumbling infrastructure.
In 2012 alone, Con Edison and National Grid, the other distributor of natural gas in the city, reported 9,906 leaks in their combined systems, which serve the city and Westchester County. More than half of them were considered hazardous because of the dangers they posed to people or property, federal records show. (There are more than 1.2 million miles of gas main pipes across the country. Last year, gas distributors nationwide reported an average of 12 leaks per 100 miles of those pipes.)
“It’s like Russian roulette,” said Robert B. Jackson, a professor of environment and energy at Stanford University who has studied gas leaks in Washington, D.C., and Boston. “The chances are, you are going to be lucky, but once in a while, you’re going to be unlucky.”
Nearly half of the gas mains operated by Con Edison and National Grid were installed before 1940, according to federal records. More than half of the mains are made of cast iron, wrought iron, or unprotected steel — materials that are vulnerable to corrosion and cracking, especially in cold weather.
Communities across the country have been struggling to replace thousands of miles of these old, metal pipes with pipes made of plastic or specially coated steel that are less prone to leakage. Few, however, face as daunting a challenge as New York City.
To replace all of the old mains in its network right now would cost as much as $10 billion, Con Edison estimates. Much of that expense would fall on the residents and businesses that use the gas for heating and cooking.
Despite the high cost and logistical hurdles, alarmed regulators at the state’s Public Service Commission have ordered the company to significantly step up its replacement schedule, from 50 miles of pipe a year to 70 by 2016, in the city and in Westchester. Even at that rate, it would still take nearly three decades for the utility to finish swapping out what regulators have identified as the most leak-prone pipes.
Gas Infrastructure Is Falling Apart in Cities Around the Country
March 12, 2014. Lily Hay Newman. Slate.com
A report out Tuesday from the Center for an Urban Future reveals that New York City’s infrastructure is extremely old. It may not be surprising, exactly, given that New York is known to have been densely populated for hundreds of years, but seeing it all laid out is still pretty stunning.
The report notes that New York’s 6,300 miles of gas mains are 56 years old and that leaks in the system cause Con Ed to lose more than 2 percent of the gas it sends to customers every year. Additionally, 60 percent of New York gas mains are made of unprotected steel or cast iron, which are no longer used in gas main fabrication because they spring too many leaks.
And New York isn’t the only city with these problems. In January, researchers from Duke and Boston University mapped Washington, D.C.’s gas leaks and found 5,893 places where the city’s buried gas mains were leaking enough methane to detect it from the street. They also noted that many sites had the potential to cause explosions. A group including several of the same researchers had similar findings about Boston in 2012.
Floods Put Pipelines at Risk Records Suggest Erosion of Riverbeds Jeopardizes Oil and Gas Infrastructure
December 3, 2012. Jack Nicas. Wall Street Journal.
Floodwater causes pipelines to fail because it’s fast and weighs a lot, so flood water can scour dozens of feet of soil and gravel from a river bed, exposing pipelines buried below.
It’s likely that pipelines need to be buried under rivers a great deal deeper than they are now – just four feet, which river engineers say is grossly inadequate.
Future problems: 24 of the 55 oil and gas pipelines beneath the Missouri river are less than 10 feet below the riverbed.
After the Exxon pipeline rupture, Montana officials pushed pipeline operators to inspect their river crossings in the state. The review found that about a quarter of the roughly 90 pipelines inspected were dangerously close to exposure.
Those findings “tell me that we’re vulnerable. But not just in Montana. The whole pipeline system across the country’s vulnerable,” Mr. Opper said.
Some examples of failed pipelines:
- An Exxon Mobil Corp pipeline on the Yellowstone River in Montana in 2011 released 1,000 barrels of crude
- An Enterprise Products Partners pipeline burst in the Missouri River floodplain in Iowa, spilling 818 barrels of a gasoline additive.
- In 1994, scouring on a flooded river near Houston exposed 37 pipelines, including eight that broke, spilling 35,000 barrels of petroleum.