The Great Molasses Flood Sounds Like A Joke, But It Killed 21 Bostonians

By | January 13, 2020

Science and poor planning caused the flood

On January 15, 1919, the Boston area found itself in a sticky situation. That afternoon, a tank full of molasses exploded while traveling through Boston, sending 2.3 million gallons of the sickeningly sweet stuff rushing through the streets of Beantown. As ridiculous as this tragedy sounds, the torrent of molasses was deadly: 21 people died, 150 more were injured, and the mess took months to clean. Dubbed "The Boston Molassacre," the accident affected the entire city, and according to local legend, the smell of molasses hung over Boston for years. Who knew that syrup could be so terrifying?

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Source: NBC News

Whenever we read about a tanker trunk loosing its product, it's usually because the vehicle has overturned, but in the case of the Boston molasses flood, it was a combination of poor planning and simple science. The truck belonged to the Purity Distilling Company, which used the vehicles to transport molasses to its ethanol plant, where it was stored for transfer at a later date. Purity tankers rose up to 50 ft. tall and held 2.3 million gallons.

At 40 degrees Fahrenheit, January 15 was a warm day for winter on the east coast. After weeks of freezing weather, it's likely that the cold molasses expanded as a result of the sudden warmth. The tank burst open around 12:30 P.M. with such force that witnesses reported what felt like an earthquake rumbling through the city. The closest bystanders said that they heard noises like a machine gun firing as the tank's rivets popped out of their holes.

The tanker was a ticking time bomb

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Source: Atlas Obscura

Decades after the explosion, multiple inquiries were made into the safety of the tanker, and it was found that the container was nowhere near as secure as it should have been. One investigation showed that Arthur Jell, USIA's treasurer, failed to perform even the most basic safety tests. It wasn't filled with water to check for leaks, and multiple groans were heard coming from the tank that were completely ignored. In 2014, a modern investigation was performed, and scientists discovered that the walls were half as thick as they should have been and far too brittle to hold that much liquid.