Aging Natural Gas Pipes: How Safe Are Our Cities?

Mar 14, 2014

Rescue workers with dogs and thermal units are searching the rubble for victims of a the gas explosion earlier this week in Manhattan, as investigators struggle to pinpoint where the leak came from and try to determine whether it was caused by the city’s aging infrastructure. Eight bodies have been pulled from the debris, but rescue workers have, so far, only cleared about half the site.

The explosion is raising questions about aging infrastructure around the country, where decades-old cast-iron pipes are still used to deliver gas. New York City is fitted with about 3,000 miles of these pipes, Boston about 2,000 miles and Philadelphia about 1,500 — all of which raises questions about public safety and what building owners, homeowners and renters can do to protect their properties and their families.

Bob Ackley owns Gas Safety USA, which consults with cities about gas leaks. He’s also conducted the Washington and Boston Gas Leak Studies in conjunction with Duke and Boston Universities. He discusses the issue with Here & Now’s Jeremy Hobson.


  • Bob Ackley, owner of Gas Safety USA, which consults with cities about gas leaks.
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Rescue workers with dogs and thermal units are still searching the rubble for victims of that gas explosion earlier this week in Manhattan. Eight bodies have been pulled from the debris, but rescue workers have, so far, only cleared about half the site. Meanwhile, investigators are trying to pinpoint where the gas leak came from and determine whether it might have been caused by the city's aging infrastructure.

And if you're thinking, well, I don't live in New York. I'm sure my gas infrastructure is more modern, you may be mistaken. Bob Ackley owns Gas Safety USA, which consults with cities about gas leaks. He's with us now in the studio. Bob, welcome.

BOB ACKLEY: Hey, thanks for having me on.

HOBSON: Well, we should first say, as we did, that it's clear - it's not clear yet whether aging infrastructure is to blame. But give us a sense of how aging our gas infrastructure is, in general.

ACKLEY: Well, the original system was put in the 1800s, the first gas systems, the 1850s or so, and it was mostly a cast iron and steel service line system. And we have now a combination of cast iron, steel, plastic, coated steel, bare steel. There's a myriad of products in the ground now, across the country. The product now for distribution systems is mostly plastic that they're trying to put in and replace the old cast iron and bare steel.

HOBSON: And are the old cast iron pipes necessarily not as safe as newer pipes?

ACKLEY: Well, there's an inherent problem with the cast iron, that it's susceptible to cracking in Earth movements, mainly from frost or earthquake, and that's a problem with the cast iron. Believe it or not, a lot of the old cast iron, if you look at it and inspect it, it's in relatively good shape. But it's the problem with the cast iron cracking from Earth movement. And also, the pipes go together every 12 feet, and there's joint leaks, a bell-and-spigot joint that leaked.

But they don't cause - have enough volume of leakage to cause an explosion like this, generally. It's more that the cracking of the cast iron from Earth movement, mainly from frost or earthquake.


Well, I'm going to jump in here, too, to ask: What do you make of the fact that residents in the area had been saying that for months they were smelling gas? And just that day, there's proof that they were, because they called utility companies. Is this something that can be gathering? Can gas be gathering for that long?

ACKLEY: Well, it's really hard to determine what odor calls came in. I did look at the press release from Consolidated Edison, and they hadn't had any recent odor complaints at that location until that morning of the explosion. So my message to anyone across the country is if you smell gas, call 911, or your emergency responders. Have people check it out and make sure that there isn't a problem.

YOUNG: Because maybe they've been telling their landlords or other people and not calling. Yeah.

ACKLEY: That falls on deaf ears. You've got to call either your fire department - that's what I would suggest - or your local utility, and they'll send a personnel generally within one hour. I see response times for most gas companies are within the 20 to 30-minute range, they're there. But if you have a hazardous situation, your fire department personnel are usually trained to assess a problem and see if there's really a hazard there. So I would suggest you call your local fire department.

HOBSON: Well, how common are these kinds of explosions?

ACKLEY: Well, they don't happen - it's relatively a rare occurrence for the amount of pipeline that's out there. But we had a recent explosion in New Jersey, which was what we call third-party damage. A contractor hit a line and caused a condominium complex to blow up. That's - a real hazard is not adhering to Dig Safe laws and utility mark outs. Anybody that's digging should call Dig Safe, whatever you call it, in your state. In Connecticut, it's Call Before You Dig. Or in Maryland, it's Miss Utility. There's got to be a name for it in California.

But it's really - before anybody digs, call. It's a free service. They'll come out and mark out all the utilities so you don't strike a line. You could hit an electric line and get killed. You strike a gas line, it could be really hazardous. So, everybody out there, before you go into the ground - and usually, it's six inches. If you're going to - if you're digging in your yard more than six inches, you're required to call Dig Safe and make sure there's no utility lines.

And a lot of times, there'll be old gas lines that nobody knows about. If you don't have service to your home, you're not using gas, you assume that there's no gas line in your yard. There may be a line going right through your yard. So you need to know that.

YOUNG: Well - and you - you've been quoted as saying that if someone is living near an 1887 small-diameter, cast-iron main gas line, they're living next to a ticking time bomb. How do you know? And what happens now? Because just the day before this happened in New York, there was a report issued talking about how there was this infrastructure that had to be replaced. It cost huge amounts of money. We know the country is late in replacing a lot of its infrastructure. But it not only cost money, it's so disruptive. You have to tear up all the streets. How is this done quickly?

ACKLEY: It's not done quickly, and it costs a lot of financial resources to this. But if you know that you have a three-, four- or six-inch in this line in New York was supposedly an eight-inch cast-iron main outside your home, it - there's an inherent risk of it cracking. And it could crack any time of year, but it's most prevalent during the frost conditions with frost coming in, frost going out and also if there's any type of earthquakes. But it can just crack for really no reason. And it's rare but you should know that if you smell gas, call 911 and get it checked out. That's the key.

HOBSON: Well, is there any move right now to update the infrastructure on a national level in a big way?

ACKLEY: Well, Senator Markey has put in some legislation to give the - some type of loan guarantees to utility operators across the country to speed up the replacement of this infrastructure.

HOBSON: You're talking about Ed Markey of Massachusetts?

ACKLEY: Yes, Senator Markey, yeah. And right now, we have plans that are sometimes 10 years, 20 years, 30 years. So if you have a cast-iron main or old bare steel main in front of your home, it may take 10, 20, 30 years if you're at the last on the line. So you should be aware of that danger near your home.

YOUNG: Well - in the meantime, you know, you say first and foremost, if you smell it, call. But there's another test. You can put some soapy water on a pipe if you think it's leaking and, what, the gas will force some bubbles to show?

ACKLEY: Well, that's on the inside piping. That's the way we test lines underground as well. When you excavate the pipe and expose the pipe, you use a soap solution to really identify where it's leaking. It's similar to a tire tube that you take out of your bicycle. You put some soap on it and you can see where the leak is. Same thing on inside piping. If you smell a little gas in your home, you should have a professional come out. But if - in the meantime, if somebody says, no, there's no problem, you can find that with just a little soap and water and a paint brush.

YOUNG: Fascinating.

HOBSON: Bob Ackley owns Gas Safety USA. Bob, thank you so much. And by the way, your daughter is singing the national anthem tonight at the Miami Heat game?

ACKLEY: Yeah. It's a big shout-out. She's doing a - for Best Buddies International.

YOUNG: Fantastic.

HOBSON: Bob, thanks a lot. You're listening to HERE AND NOW. Transcript provided by NPR, Copyright NPR.