January 15th of 1919 was unusually warm for a winter day in Boston. It wasn’t hot by any means, the high for the day was only 40 degrees Fahrenheit, but that was a huge improvement from the frigid 2-degree weather the inhabitants of Boston had to endure for the two days prior. What the people who lived in the North End of Boston didn’t know (how could they after all?) was that this change in temperature was about to cause America’s stickiest and perhaps most impactful disasters.
The cause of the disaster was a giant, fifty-foot tall storage tank that was being used by US Industrial Alcohol to store over 2.3 million gallons of molasses. It goes without saying that this was a lot of molasses, over four Olympic swimming pools worth, but I’m going to say it anyway. What also needs to be said is that molasses, especially cold molasses, is really dense. The full tank weighed around 12,000 tons and when the rapid change in temperature produced gas, the pressure became too much for the tank to hold.
When the metal container holding what can only be described as a shit ton of molasses burst, it caused a title wave of sticky terror that destroyed buildings in a two-block radius. The wall of molasses was said to be around 25 foot high and traveled 35 miles per hour, killing 25 people (plus several horses) and injuring another 150 people. The aftermath was so sticky that even many of the people who attempted to rescue those trapped in the muck lost their lives as well.
One of the survivors, Martin Clougherty, was sleeping at his home with his 65-year-old mother, sister, and brother. To his horror, he woke up to find out that his house had been pushed off of its foundation and was being crushed against the tracks of an elevated train line nearby. His mother was never found and his brother died later in a mental institution where he was admitted due to trauma from the flood. He explained that “the buildings seemed to cringe up as though they were made of pasteboard.” Pasteboard, I learned, is what they called construction paper at the time.
A class-action lawsuit was filed against US Industrial Alcohol—one of the first of its kind. The company tried to blame it on the boogie man of the time, anarchists. Much of the alcohol being produced at the site was being used for munitions so there certainly was a motive to do so but an investigation later found that negligent construction was to blame. The facility was built at the height of WWI and authorities were more interested in increasing the production of munitions than reducing the risk of a molasses flood so the container was built with about 50 percent less steel than was required for the weight. Making matters worse the steel that the tank was made out of, the same that used in the Titanic in fact, was an imperfect blend of magnesium and iron that made it susceptible to cracking.
The success of the lawsuit and the public outcry over the horrific tragedy had an important positive benefit. To prevent similar disasters the city required an engineer to sign off on the designs of any new structure, whether it was a housing development or syrup storage. This requirement was later adopted by other cities around the country and quickly became standard practice. Despite building permit and inspections processes often being as slow as—well you know—they have undoubtedly saved many lives in the century since the US Industrial Alcohol lawsuit.
