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A Monumental Disaster: What Happened in the Boston Molasses Flood

Jule Romans is the author of "Shakespeare Love Quotes" and other books. She has 30 years of experience writing on educational topics.

Newspaper photo of the Boston molasses flood

Newspaper photo of the Boston molasses flood

Molasses Destroys a Town

Two and a half million gallons of sticky liquid molasses poured through a burst tank, destroying buildings, drowning people, and devastating everything in its path. This nearly unbelievable disaster actually happened in the north end of Boston on January 15, 1919. The damage lasted for years.

A Tidal Wave of Syrup

According to the Boston Post, a wave of molasses, 50 feet high, flowed at almost 35 miles per hour, throughout the North End of Boston. The huge wave destroyed everything in its path.

It would be funny, if it weren’t so terribly destructive.

The Boston Post headline reads:

"Huge Molasses tank explodes in North End; 11 Dead, 50 Hurt."

Beneath the headline, the bold print claims:

Giant wave of 2,300,000 gallons of molasses 50 feet high sweeps everything before it. 100 men, women and children caught in sticky stream. Buildings, vehicles, and L structure crushed…Search for more victims during the night. No escape from gigantic wave of fluid.

Catastrophic Failures

The Boston Molasses Flood of 1919 was caused by the failure of a 50-foot tall storage tank in the North End of Boston.

A 50-Foot Tall Storage Tank For Molasses

The molasses disaster started with the United States Industrial Alcohol (USIA) Company four years before the disaster. The USIA built a 50 foot tall storage tank for its Purity Distilling Company in 1915. The Purity Distilling Company was a subsidiary of the USIA.

This distilling company fermented molasses specifically for the purpose of creating industrial alcohol.

Molasses Was Needed for Munitions in World War I

According to The Census History website, "The molasses stored in the Boston storage tank was destined to be fermented into industrial alcohol, also known as ethyl alcohol, or “ethanol.

Industrial alcohol was needed to produce cordite—a smokeless gunpowder used in ammunition and artillery shells. This was critical to the war effort. At the time, World War I was in full swing, and the munitions industry had an unceasing need for industrial alcohol.

USIA was eager to take advantage of some highly valuable war contracts.

Haste Makes Disaster

The Boston Molasses Flood was caused by hasty construction based on shipping errors and time constraints. The faulty tank, improper inspection, and hasty actions combined to cause an unnatural disaster.

The tank that held the massive quantities of molasses had to be constructed with undue haste in order to offload the great quantity of molasses. Officials and supervisors had limited engineering knowledge. They did not have the expertise to identify critical flaws in the tank’s materials and construction.

The first shipment of molasses arrived from Cuba and was waiting in Boston before all the details were completed. The tank was not inspected for leaks. It was filled with molasses anyway. Millions of gallons of molasses were poured into the faulty tank.

Harbingers and Warnings Unheeded

That flawed tank was active for four more years. It continued to be used for the storage of molasses from 1915 to 1919, without adequate inspection or repair. For four years, the huge tank groaned and creaked under the pressure of its contents. Residents of the neighborhood became accustomed to hearing the sounds.

The US Census Historical website recounts that: “Rivets and seams leaked so profusely that families regularly collected molasses dripping down the tank walls for home use. In response, USIA ordered the tank painted brown to help camouflage its leaking joints.”

Delivery and the Deluge

In mid-January of 1919, a huge delivery of molasses arrived in Boston. The S.S. Milerro pumped 600,000 gallons of molasses into the USIA storage tank on January 12-13, filling it nearly to capacity.

A Tank Under Pressure

The tank was now groaning with a full load of more than 2 million gallons of molasses. It was planned that the molasses would be transferred to railroad cars within a few days. Those cars would take the molasses to a distillery in Cambridge. That delivery didn’t ever have a chance to happen.

From January 12 to January 14, the tank held. A few short hours later, the pressure proved to be too much.

The Molasses Tank Breaks

On January 15, at 12:40 p.m., the trouble began. It started with a rumble. Residents of the neighborhood could hear the sounds. At the time, they may have been accustomed to the tank making noises. Perhaps they didn’t find it unusual.

The next sounds, however, must have been terrifying. There was a noise of metal splitting with great force. The tank’s steel walls tore apart. The molasses exploded outward under extreme pressure.

At the time, it was unclear whether the disaster was a result of a collapse or an explosion. In either case, the force was tremendous. The damage was terrifying.

The Molasses Flood

Molasses, sticky, viscous, and suffocating, poured into the neighborhood. It overwhelmed and engulfed everything in its path. Onlookers were suffocated. Many did not survive, essentially drowning in syrup. Other victims were swept along in the inexorable tide and washed right into the harbor.

Months of Misery

It took days to sort through the wreckage. Rescuers searched for people who were injured and killed. The rescue and recovery effort continued for months. The last victim was recovered from the harbor on May 12, 1919--a full five months after the tragic event

The Victims

Twenty-one people died from injuries related to the Boston Molasses Flood. A few of the victims have tragic stories.

  • Bridget Cloughtery, Victim of House Collapse. Age 65. Died in a house collapse. Her home was inundated by the wave of molasses. The building was completely flooded, and decimated by liquid. Several lodgers were also injured in the home’s destruction. Bridget’s children Stephen, Martin, and Theresa survived their injuries. Stephen died months later at the Boston State Asylum for the Insane. It is believed that his decline and death were resulted from the molasses flood incident.
  • John Seiberlich, Crushed by Debris. Age 69. Blacksmith. Died from skull fracture and other injuries. John was crushed by wreckage because her was occupied with important tasks near the broken storage tank.
  • Patrick Breen, Swept into Boston Harbor. Age 44. Laborer. Swept into Boston Harbor. Contracted pneumonia and multiple internal injuries a few days afterward.
  • William Brogan, Trapped and Flooded. Age 61. Teamster. Trapped, and overwhelmed by the flood. William was employed at the City of Boston’s North End Paving Yard, which was adjacent to the USIA property. He did not have the opportunity to escape.
  • George Layhe, Drowned. Firefighter. Drowned. His fireboat station was shattered, and George was trapped in the debris. He drowned in molasses, not water.
  • James McMullen, Overcome by Internal Injuries. Railway foreman. Died from internal injuries and infection. His death came days after the flood.

Cleaning Up the Mess

It took an estimated 87,000 work hours to clean up the mess. Workers spent hours cleaning streets, buildings, trains, and everything else the sticky syrup touched. Making the situation more difficult, pedestrians and horses tracked sticky footprints of molasses all over the city. The US Census History site reports that “Years after the flood, North End residents claimed they could still smell molasses in the neighborhood on warm days.


In the aftermath of the tank’s failure, the victims’ families filed a class-action lawsuit against USIA. USIA deflected responsibility, claiming the rupture had been the result of a terrorist act by anarchists.


After six long years of hearings, Mr. Hugh Ogden was appointed as auditor overseeing the lawsuit. Working on behalf of the Massachusetts Superior Court, Ogden found in favor of the victims.

He concluded that the tank’s was improperly constructed. He ordered USIA to pay the victims of the molasses flood one million dollars. At that time, this was a significant amount of money. It might be equal to approximately 18 million dollars today.


There was one positive outcome. Not long after the great molasses flood, regulations were put in place that were much more effective than the ones in place in 1919.

Inspection and maintenance of storage tanks came under much more scrutiny. Permitting had stricter enforcement, not only in Boston, but also across most of the US.


The place where the USIA molasses storage once stood is now occupied by a park and baseball field. Nearby, there is a small plaque, not easily noticed by the casual observer. In a few short sentences, the plaque stands for the memory of the Boston Molasses Flood and the 21 victims who lost their lives as a result.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2020 Jule Romans