Federal officials investigating the gas leak and deadly explosion that collapsed two Harlem tenements Wednesday are also examining how the Manhattan gas utility responsible for pipeline maintenance had responded to complaints of gas odors.
Firefighters Thursday sifted the wreckage for people still missing after the massive explosion, which killed at least seven people and injured scores.
A team from the National Transportation Safety Board, the federal agency that investigates serious pipeline accidents, arrived at the scene Wednesday evening, saying they would determine a timeline of events and look into how the utility handled the reports of gas odors.
“We will be looking at Con Edison’s integrity management system,” said the NTSB’s Robert Sumwalt at a Wednesday press conference at the scene of the blast. “We will be looking at their call system to see how they handle complaints.”
A number of witnesses said they smelled gas for several days before the blast, and just 18 minutes before the explosion a resident called the utility and complained of a strong gas smell.
“We want to understand the failure modes,” Mr. Sumwalt said, adding that the federal investigators expect to make recommendations to “make sure that something like this never occurs again.”
But across the United States there have been an alarming number of other gas-related explosions, and experts say the nation’s aging infrastructure – as well as a decline in gas utility inspections and routine maintenance – is putting many regions of the country at risk.
“It’s becoming an epidemic,” says Mark McDonald, a gas explosion expert onsite in Harlem Thursday afternoon. “It’s happening way too often and much more often than it used to, that’s for sure.”
And Mr. McDonald, who has investigated gas explosions around the country with NatGas Consulting and has been a leading expert witness in most major gas explosion litigation, had just driven to New York after being onsite investigating another major explosion in New Jersey.
Just last week, a gas leak sparked a massive explosion in a suburban townhouse development in Ewing, N.J., engulfing dozens of houses in flames, killing a 62-year-old woman, and injuring seven others. At least 55 homes were damaged, including 10 that were completely destroyed.
These incidents, too, follow a month in which a number of other explosions rocked cities across the US.
• On Feb. 22, two women in their 20s were seriously injured when a gas explosion blew out the wall of a two-story house in Chicago, sending debris into the streets.
• On Feb. 19, an 8-year-old boy was killed when a gas leak caused an East Baltimore row house to explode. The building collapsed onto the sidewalk where the small boy was walking home from school. Rubble from its two collapsed floors also injured 3 other bystanders.
• On Feb. 14, two homes were destroyed and two people were injured in a small south-central Kentucky town in a fire in the aftermath of a massive gas line explosion that blew a crater 60 feet deep and 50 feet wide.
There was also a series of major natural gas explosions last year. Last October, a blast destroyed a house and killed an 11-year old girl in rural West Virginia, and in November, another major blast obliterated a downtown Springfield, Mass., strip club, injuring 18 people. In February last year, a Kansas City restaurant blew up after a gas main break, killing a worker and injuring more than a dozen others.
Indeed, in 2013, there were at least 109 gas-related incidents, including 21 serious leaks and explosions that led to 9 deaths and 39 injuries, according to the Pipeline & Hazardous Materials Safety Administration in the US Department of Transportation. The death toll from the Harlem blast alone could exceed these fatalities, and more than 60 injuries have been reported so far.
And while the nation’s old pipes may be to blame – the gas main leading to the Harlem tenements was a century-old cast iron pipe – experts say the nation’s utilities have been cutting staff and relying on private companies to inspect and maintain their infrastructure.
“The other factor is essentially deregulation,” says McDonald, the gas explosion expert. “The gas company staffing has been reduced by around 20 percent since deregulation was instituted both in states and nationally,” he says. “On the other end, customers have increased by more than 20 percent, so how do you add 20 percent more customers and at the same time cut staffing by 20 percent or so? It doesn’t make sense.”
The US consumed a total of 26 trillion cubic feet of natural gas in 2013, up nearly 20 percent since 2006, when it consumed 21.7 trillion cubic feet, according to the US Energy Information Administration.
In January, the New York Public Service Commission unanimously decided to conduct an audit of the staffing levels in the state's core utility companies. This after Gov. Andrew Cuomo called for improvements following the generally poor performance of New York utilities’ in the aftermath of superstorm Sandy.
Experts say previous audits of utilities have found that consumers bear the brunt of lower staffing levels, which lead to more service interruptions and slower responses during system failures.
“The state gets their expertise from the companies, so there's a lot of conflict of interest, in my opinion,” says McDonald. “So I think the federal government has to take a more assertive role in enforcing all the regulations and all the rules. The state’s aren’t doing enough – and they’re very close to the companies.”
“The NTSB would be great – or some agency like that where there is no interaction with the companies and they could be a true watch dog,” McDonald continues. “The public is starting to put things together and say, wait a minute, what the hell is going on here? Because next it could be your backyard.”
[Editor's Note: The original version of this article misstated how much natural gas the US consumed in 2013 and 2006.]