Ep 56 Boston Molasses & London Beer Floods
This week we're taking a much needed break and featuring two of our mini failure episodes from early this year.
Boston Molasses Flood - Over 100 years ago, A wave of molasses flooded the streets of North End in Boston and took out everything in its path.
London Beer Flood - A failed vat sent a huge wave of beer down London streets.
Sources:
Boston Molasses Flood
London Beer Flood
Episode Summary
Hi and welcome to Failurology; a podcast about engineering failures. I’m your host, Nicole. And I’m Brian.
Our podcast journey has been a wild ride and we are immensely thankful for all of your support throughout the course of our show. Especially to our Patreon supporters.
But we need a bit of a break this summer.
And we didn't want to stop giving you those engineering failures you know and love.
So today we’re sharing some more of our mini failures. This time we’re sharing two shorter episodes; the Boston Molasses Flood and the London Beer Flood.
In both cases, giant vats used to store molasses and beer failed and sent waves of liquid throughout the streets of Boston and London.
So without further adieu, here is our mini failure on the Boston Molasses Flood, with the London Beer Flood episode to follow afterwards.
Boston Molasses Flood
Hi and welcome to Failurology; a podcast about engineering failures. I’m your host, Nicole
And I’m Brian. And we’re both from Calgary, AB.
Welcome to our 14th mini-failure episode.
We’re bringing you engineering failures in bite-size pieces.
Make no mistake, these are still significant failures, but they either have pretty straightforward causes or not enough information available for a full episode.
Essentially, we have a list of failures we want to tell you about.
These episodes are also just the failure, no news and no ads (for now at least).
It’s like Failurology-lite.
This week’s mini failure is about the Boston Molasses Flood.
Also known as the Great Molasses Flood
Jan 15, 1919 at approximately 1230pm in the North End neighborhood of Boston
At Purity Distilling Company at 529 Commercial St (which is now a park)
They used the molasses to ferment into ethanol and make alcoholic beverages and munitions
The tank was a storage tank to offload molasses from ships to be transferred later by pipeline to Purity’s ethanol plant about 3.5km away in the Wellington-Harrington district
The tank had only been filled to capacity 8 times since it was constructed. This accident occurred shortly before prohibition and it was believed that Purity Distilling Company was trying to sell as much alcohol as possible before prohibition set in
Cause - cylinder stress failure
8.7 million L tank of molasses weighing about 12,000 tons
15m tall and 27m in diameter
Temperature raised from -17 to 5C in a short period of time
The tank was poorly constructed and insufficiently tested. They didn't even try filling it with water to check for leaks
A ship had delivered molasses the previous day which had been warmed to made it more viscous for transfer
The working theory is that the new warmer molasses may have heated and expanded the colder molasses already inside the tank and as 1230pm the tank burst open
The failure occurred from a manhole cover near the tank base and then grew until complete failure. The rivets were also flawed and cracks had formed at the rivet holes
Witnesses heard a roar, the ground shook and then a long rumble. Others heard a thunderclap type crash
The molasses was about 40% more dense than water and had a great deal of potential energy
The wave of molasses was 8m high at its peak and moved through the streets at 56 kph
The wave was so strong it pushed the tank into the elevated railway structure and almost knocked a streetcar off the tracks
Several blocks were flooded to 60-90cm and buildings were knocked off their foundation and crushed
21 died, 150 injured
Residents claimed for decades that the area smelled like molasses on hot summer days
A class action lawsuit was brought against the owner. It was the first of its kind in Massachusetts and is said to have paved the way for modern corporate regulation.
The owner paid out $628,000 in damages which is equivalent to about $9.37 million
Many groups have investigated the failure since 1919
One group found that the steel walls of the tank were only about half as thick as they should have been and that the steel lacked manganese and was more brittle as a result
Student researchers at Harvard concluded that the high speed flood claims from witnesses were credible
Many laws and regulations were added as a result of this accident such as requirements for architects and civil engineers to oversee these types of construction.
One of Boston’s duck boats are named Molly Molasses in remembrance of the event
So there you have it, the Boston Molasses flood. A wave of molasses flooded the streets of North End in Boston and took out everything in its path. Like all of the failures we’ve covered, lessons were learned and new regulations were added to prevent this type of incident from happening again.
Thanks for listening to this mini-failure episode. For our regular episodes, check out Failurology wherever you get your podcasts.
If you want to chat with us, our Twitter handle is @failurology, you can email us at thefailurologypodcast@gmail.com, or you can connect with us on Linked In. There are links to all of these in the show notes.
Bye everyone, talk soon!
London Beer Flood
Hi and welcome to Failurology; a podcast about engineering failures. I’m your host, Nicole
And I’m Brian. And we’re both from Calgary, AB.
Welcome to our fifteenth mini-failure episode.
We’re bringing you engineering failures in bite-size pieces.
Make no mistake, these are still significant failures, but they either have pretty straightforward causes or not enough information available for a full episode.
Essentially, we have a list of failures we want to tell you about. A long list!
These episodes are also just the failure, no news and no ads (for now at least).
It’s like Failurology-lite.
This week’s mini failure is about the London Beer Flood
Oct 17, 1814
Meux (Mew) & Co’s Horse Shoe Brewery in london
Corner of Tottenham Court Rd and Oxford St
The owner Henry Meux’s father had created the largest vat in London capable of holding 20,000 imperial barrels.
In an effort to emulate his father, Henry built a vat of his own out of wood at 6.7m tall and capable of holding 18,000 imperial barrels. He used 81 metric tons worth of iron hoops to strengthen the vat and hold the wood slats in place. Similar to a wooden barrel, but much much larger
Around 430pm on Oct 17, the storehouse clerk noticed one of the iron bands around a vat had slipped.
The vat had 3,555 imperial barrels of 10 month old porter in it at the time, which was within 10cm of the top of the barrel.
The bands slipped was not abnormal, so they weren’t too concerned. It needed to be dealt with but wasn’t overly urgent.
An hour after the hoop slipped off, the vessel burst. The force of the liquid knocked the stopcock from the neighboring vessel and it discharged its contents.
Between 128,000 and 323,000 imperial gallons were released
In addition to destroying other vats, the wave of porter destroyed the rear wall of the brewery which was 7.6m tall and two and half bricks thick.
A 4.6m wave of liquid swept down the street and destroyed two houses and damaged others.
The land around the brewery was low lying and flat and porter flooded into several occupied cellars forcing people to scramble onto furniture not to drown.
Records show that 8 people died due to the flood
This was ultimately determined to be an act of god, which would not fly today, and Meux & Co didn’t have to pay compensation. They did lose 23,000 pounds which is equivalent to $365,000 USD today in lost beer, building damage and the replacement vat.
As a result of the accident, large wooden tanks were phased out of the brewing industry and replaced with concrete ones. Today they use stainless, sometimes plastic and still oak barrels but on a much smaller scale.
So there you have it, the London Beer Flood. A giant wall of beer smashed the brewery wall and sent a huge wave of beer down London streets.
Thanks for listening to this mini-failure episode. For our regular episodes, check out Failurology wherever you get your podcasts.
If you want to chat with us, our Twitter handle is @failurology, you can email us at thefailurologypodcast@gmail.com, or you can connect with us on Linked In. There are links to all of these in the show notes.
Bye everyone, talk soon!