Pretty gigantic explosion to flatten 3 brick houses.

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Gas explosions in houses often results in complete demolition. Once one falls down any other using it for support also collapse.

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Doesn't look like much of a down component there. I think it all went up.

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

I wonder if most of the gas was in the center house and it took out the houses on each side of it.

Bill
--------------------
"Why not the best?"
Jimmy Carter

your pipe work is rubbish and nobody cares about it.

Your main trunking pipe work is dodgy as hell and there is extremely limited work ticket standards enforced and there is zero political pressure to generate anything sensible. Your just going to have to accept that these things happen occasionally

Errr some rather sweeping generalisations there Alastair.

Few pints in?

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I think is still not confirmed as a gas explosion, but I certainly bet that it will be. It's got all the earmarks. Nothing left bigger than a matchstick. Just missing a massive fire, so it was accumulated leakage rather than a mains break. The gas distribution system has the oldest pipe in the entire country some dating from 1817. Of course far too expensive for a profit motivated company to properly maintain or replace.

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

I think we are at a different level. Here we are still trying to get the lead out of our water piping.

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

The last one was. And now gone.

We had huge issues with our gas main in Scotland. Getting the water main upgraded was relatively easy.

They seemed to work with the gas that if it wasn't leaking then don't touch it. There was 2 years of fixing leaks before they replaced the whole thing.

Mine is now all external and doesn't go near any enclosed spaces in the building. It used to route through the foundations.

This issue with old gas pipes isn't country specific and neither is the zero political pressure to get it sorted. They don't seem to know which way they want to go with gas and they don't want to upgrade the current infrastructure which in my area was over 50 years old.

The digging up the street 3 times in the space of 12 months though due to nobody from the utility's talking to each other was particularly annoying.

No information yet if this was a gas leak inside the dwelling, or outside. However a pipeline leak would not surprise me. Particularly troubling is that when oderized natural gas peculates through enough dirt, the odorant can be stripped out, resulting in there being no obvious indication (Mercaptan smell) of a natural gas accumulation.

The US pipeline regulator is strongly encouraging gas distribution utilities to replace cast iron and bare steel distribution pipelines and service taps. Some locations are farther along than others, likely has something to do with the willingness of the local regulators to allow cost recovery for the replacements.

Pipeline Replacement Background (Pipeline and Hazardous Materials Safety Administration) https://www.phmsa.dot.gov/data-and-statistics/pipe...

Scorecard (per above site) MD still has 1,111 miles of cast iron distribution pipe in service.

This is the area... sounds like two dead so far...
https://www.google.com/maps/place/4200+Labyrinth+R...

Dan - Owner
http://www.Hi-TecDesigns.com

These specific houses. Image is a bit fuzzy; my network isn't at full speed.
https://www.google.com/maps/@39.3577546,-76.710068...

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The tree looks to have lost some leaves...

Rats, still might not be the right houses, the numbers don't match

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Was this some kind of public housing project? Can't imagine anyone but the government building something so unappealing.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

Quote:

Can't imagine anyone but the government building something so unappealing

Yah. No kidding.

Keith Cress
kcress - http://www.flaminsystems.com

What age are those?

It looks like a post 80's if not 90's development. I would have thought they would have newish pipes from the utilities.

According to Redfin, these townhouses were built in 60s. Footage ranges from 1100 to 1300, ASP around $100k, so not public housing, per se. The middle unit last sold in 2007 for $100k.

https://www.redfin.com/MD/Baltimore/4232-Labyrinth...

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60 year old pipes then. As FacEngrPE says the soil will take the smell away.

What we were finding was that because the pipes were under tarmac under the road it then came up the outside of the pipe into the foundations. Two leaks were only discovered because the owners were tanker engineers and had gas detectors in the foundations. Came back from a tour on the boat and the wife was complaining she could hear a beeping noise from under the floor. They then went and drilled holes in the road and put a sniffer probe in to try and find them.

When they replaced everything the pipes got rerouted so the meter was outside.

Many houses in that era probably used either cast iron or "black iron" pipes set in the concrete screed or under the floor boards to pipe it internally. Often screwed joints as well.

When our old house got connected to the mains well after the house was built we had a gas leak inside the house where a carpet gripper nail had punctured the pipe laid all of 1" below the top of the concrete screed....

But gas spreading along pipes from a leak in the mains is also pretty common.

Would be interesting to know if there was a void under the houses or not, i.e suspended floor or solid floor.

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Update

https://www.baltimoresun.com/maryland/baltimore-co...

https://www.baltimoresun.com/news/environment/bs-m...

https://en.m.wikipedia.org/wiki/Baltimore_Gas_and_...

https://en.m.wikipedia.org/wiki/Exelon

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

Quote from the links above:

BGE, the nation’s oldest gas utility with origins dating to 1817, likely needs to replace thousands of miles of obsolete pipes.

Chris Burton, BGE’s vice president for gas distribution, testified before the Maryland Public Service Commission in mid-May, providing an update on the company’s aging infrastructure.

About one-third of its gas distribution mains, one-quarter of its gas services and half of its transmission mains are older than 50 years old, he said. Roughly 15% of its massive gas distribution system is made of “outmoded materials.”

Gas leaks are so frequent that nearly two dozen of them are discovered each day, on average, according to data BGE reports to federal authorities. The number of leaks increased by 75% from 2009 to 2016 — amid what officials called a “dramatic” increase in the failure of pipe joints dating from the 1950s and 1960s.

----------------------------------------

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Parent company, Exelon, generates $33 billion per year, but somehow cannot seem to make a plan to replace old pipe in Baltimore Gas' system in less than 20 years with budget of $1 Billion. Note that is only $50 million/yr, although spending 24 M installing smart meters. Well I guess pretty soon they will know exactly how much they lose to leaks.

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

IR, I think you're in the correct spot... I marked the location at the start of the block just a few units away. What prevented the unit to the left from being destroyed was the gap between the multi-units.

For those who are mentioning the soil scrubbing the smell... the article states several people complained about smelling gas.

Dan - Owner
http://www.Hi-TecDesigns.com

Yeah, I was having trouble reading the house numbers in the photos initially, but I think everything is tracking; the Redfin data is for the middle of the three that were completely obliterated, i.e., the one that was adjacent to the end unit, next to the gap, in that group.

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Quote:

Was this some kind of public housing project? Can't imagine anyone but the government building something so unappealing.

Welcome to Baltimore. If I had to guess, I'd say that well over 90% of the housing stock is rowhouses; their curb appeals cover a rather wide range, with the median being on the lower side. It's a poor city that's long been plagued by a lot of problems. That said, in the little bit of real estate shopping I've done for homes in England, stuff over there strikes me as pretty fugly, too, and much more expensive.

Quote:

BGE, the nation’s oldest gas utility with origins dating to 1817, likely needs to replace thousands of miles of obsolete pipes.

They are replacing the lines. I think it was last year that they finished my neighborhood. I don't know what the timeline is for finishing the whole city.

Quote:

Many houses in that era probably used either cast iron or "black iron" pipes set in the concrete screed or under the floor boards to pipe it internally. Often screwed joints as well.

Something odd I found once I moved here - in my neighborhood (~5 miles away, houses built in the 1920's), adjacent pairs of rowhouses share a feed from the street, with the split being located in the basement of one of the units, upstream of the individual meters.

Quote:

Would be interesting to know if there was a void under the houses or not, i.e suspended floor or solid floor.

They all have full-height basements.

The gas lines in our house, to the dryer (which is capped off), to the furnace and to the fireplaces, are all iron pipe with threaded connections. Our house was built in 1978 and met all relevant building codes, including earthquake codes, for SoCal.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

It probably still does.

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

When you get gas work done in the UK in your house, they first test your existing pipework with a manometer - so inches of water column pressure, i.e. bugger all.

You then get acquainted with the concept of an "acceptable" leak / pressure drop over a minute.

To get an old system to seal 100% through all valves / joints etc is next to impossible and likely to disturb the pipework trying to find an impossibly small "fugitive" leak somewhere in pipes which are under floor boards, buried in screeds / concrete etc etc

Does make you think a bit though....

By far the best detection device is mounted on the front of your face.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

As far as fixing these obsolete gas pipes in the good old USA, there's two issues:

1. All gas utilities, to my knowledge, are private entities. It's very hard to pressure them to do any kind of preventative maintenance. If you have a decent lobbyist, you can literally get away with murder. They'll dilute the requirements until they're meaningless.
2. It's very hard to capture the costs. You can't really charge more for your product if it's going through better pipes. Until you're losing money due to leaks, it's hard to justify.

And if the leak is inside a house, it's another set of problems.

There used to be a time when utilities were private, but regulated, so they could be forced to do the right thing; but some people had this silly idea that utilities could be self-regulating, LOL.

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And provide service "more efficiently", read cheaper, in the process. How many times are we going to fall for that line of reasoning? It is a more efficient alchemy process though, changing iron, now plastic, into gold, especially without any maintenance costs. Dont even have to pay your metals broker, or your alchemist any more.

Sort of like the arguments that we've been hearing of late about making the Post Office a for-profit operation, eh?

Note that the Post Office was established by the United State Constitution in Article I, Section 8, Clause 7 and there is nothing about it making a profit. BTW, clauses 12 and 13 of that SAME Section of the Constitution establishes the Army and Navy, respectively, and there's no mention of they being profit-making organizations either.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

True, but USPS directly charges for services, while the DoD does not.

Quote:

And provide service "more efficiently", read cheaper, in the process. How many times are we going to fall for that line of reasoning?

And it is cheaper, since the utilities can still turn profits and can pay off billions of fines and claims; it's just not "better" service, but no one seems to care about that.

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Quote (IRstuff)

True, but USPS directly charges for services, while the DoD does not.

Haha. You think people have a bad opinion of the, otherwise successful if not for the absurd restrictions/mandates congress imposed and continues to impose, self-funded USPS for running a deficit?

Imagine if people saw the per capita bill for DoD's services.




Can you tell I was raised by a USPS mail carrier?

Andrew H.
www.MotoTribology.com

Quote:

Imagine if people saw the per capita bill for DoD's services

Meh, a measly $2k or so per capita; that's only about 4000 stamps.

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The DOD may not make money directly, but they make everybody else make a lot of money and that's even better. You only lose on the stuff that actually explodes and those are really only short term losses.

This situation with the infrastructure is not unique to USA, its the same in the UK.

Alot of it I suspect is the fact that there are no bonuses involved in upgrading the infrastructure. The only time they will do it is if they are forced to, by something going bang or the leaks quantity starts reducing profits and bonuses. Or the regulator/ H&S force them to.

I very much doud't our street would have had a new mains installed if it wasn't for the two gas tanker marine engineers who had access to all the sniffer gear and me using a mate in the HSE.

It seemed to me that having the gas pipe entering the property in a still air void area in the foundations was asking for problems. Which is why I got mine moved outside. Now I only have 6 meters of gas pipe internally to the central heating burner. All copper from the meter and pressure tested to 5 bar for 48 hours no pressure drop. Which I did myself and the Gas bloke who came to put the burner back online was most impressed with. "we just don't have the time or ability to do a proper pressure test like that, it would mean 2-3 visits per job. "

Leakage in itself is not an incentive to make repairs. True. The transportation clients and ultimately the consumers pay for lost gas leakage. It is an accounting line item known as "unaccounted gas".
https://www.clf.org/wp-content/uploads/2013/08/Mar...

How much gas leaks [from pipelines]
https://www.scientificamerican.com/article/how-muc...

A history of the enforcement of mains replacement in the UK.

Basically it's in the legislation and whilst 30 years is a long time, there is a plan.... https://www.hse.gov.uk/gas/supply/mainsreplacement...

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I think that must have been the legislation that my mate triggered in 2005

It was taking the piss though with us. After the first tanker guy moved in down the road and had his alarm went off went it was nearly 18 months of constant issues after we became aware of it. The solution was to put ventilation into void areas at our own cost.

When they dug the road up for the water main it was the final straw because we got pictures of it. Colossal flakes of rust coming off it. The marine guys used a ultrasonic thickness meter on it and it was down to 1/3 thickness in places until they got banned from going near it. Although I presume the surrounding streets had similar issues they didn't get replaced until they did the main pipe 10 years later.

You could make distribution pipe out of paper and it wouldn't burst from pressure. It's the joints which are the problem in old cast iron mains and brittle cracks caused by vehicles pounding the roads.

But mainly the joints which were made from dope wrap and sealed with lead. Any movement and hisssss.

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Not to mention outright external corrosion.

The system can work as presented by IRstuff. Right now I can hear the construction equipment replacing an old SDG&E high pressure gas line under mandate from the Ca Public Utilities Commission, all prompted by the explosion in San Bruno. We, the gas customers pay for it, but that's money I'm happy to spend.

Yes, but would you be happier and safer, if you didn't have to pay for leaked gas that endangers eveybody. Gas companies should be responsible for leaked gas, as that would at least give them some tiny incentive to get busy fixing the leaking pipes. The problem now is that they only care after something blows up. And they don't care to fix pipes even if it means carrying a billion dollars of potential risk. Why? They have insurance companies for that. Then when somebody gets killed, they can barely manage to keep a straight face long enough to say they're sorry.