Great Molasses Flood

The Great Molasses Flood, also known as the Boston Molasses Disaster,<ref>Template:Cite web</ref><ref>Template:Cite web</ref>Template:Efn was a disaster that occurred on Wednesday, January 15, 1919, in the North End neighborhood of Boston, Massachusetts.

A large storage tank filled with Template:Convert<ref>Template:Cite news</ref> of molasses, weighing approximatelyTemplate:Efn Template:Convert burst, and the resultant wave of molasses rushed through the streets at an estimated Template:Convert, killing 21 and injuring 150 people.<ref name="Sohn">Template:Cite web</ref> The event entered local folklore and residents reported for decades afterwards that the area still smelled of molasses on hot summer days.<ref name="Sohn" /><ref name=Smithsonian />

Flood

Coverage from The Boston Post

Molasses can be fermented to produce ethanol, the active ingredient in alcoholic beverages and a key component in munitions.<ref name="DarkTide" />Template:Rp The disaster occurred at the Purity Distilling Company facility at 529Template:NbsCommercial Street near Keany Square. A considerable amount of molasses had been stored there by the company, which used the harborside Commercial Street tank to offload molasses from ships and store it for later transfer by pipeline to the Purity ethanol plant situated between Willow Street and Evereteze Way in Cambridge, Massachusetts. The molasses tank stood Template:Convert tall and Template:Cvt in diameter, and contained as much as Template:Convert.

Modern downtown Boston with molasses flood area circled

On January 15, 1919, temperatures in Boston had risen above Template:Convert, climbing rapidly from the frigid temperatures of the preceding days,<ref name=DarkTide />Template:Rp and the previous day, a ship had delivered a fresh load of molasses, which had been warmed to decrease its viscosity for transfer.<ref>Template:Cite web</ref> Possibly due to the thermal expansion of the older, colder molasses already inside the tank, the tank burst open and collapsed at approximately 12:30Template:Nbsp.m. Witnesses reported that they felt the ground shake and heard a roar as it collapsed, a long rumble similar to the passing of an elevated train; others reported a tremendous crashing, a deep growling, "a thunderclap-like Template:Em", and a sound like a machine gun as the rivets shot out of the tank.<ref name=DarkTide />Template:Rp

The density of molasses is about Template:Convert, 40 percent more dense than water, resulting in the molasses having a great deal of potential energy.<ref name="nbc 100" /> The collapse translated this energy into a wave of molasses Template:Cvt high at its peak,<ref name="SciAmJabr" /> moving at Template:Cvt.<ref name="Sohn" /><ref name="Smithsonian" /> The wave was of sufficient force to drive steel panels of the burst tank against the girders of the adjacent Boston Elevated Railway's Atlantic Avenue structure<ref>Template:Cite web</ref> and tip a streetcar momentarily off the El's tracks. Stephen Puleo describes how nearby buildings were swept off their foundations and crushed. Several blocks were flooded to a depth of Template:Cvt. Puleo quotes a Boston Post report:

As molasses is a non-Newtonian fluid, its viscosity changes under stress, thinning and flowing quickly under pressure and heat. During the flood, this shear-thinning resulted in unexpected speed.<ref name=":0">Template:Cite web</ref> A 2013 article in Scientific American stated:

"A wave of molasses does not behave like a wave of water. [...] A wave of molasses is even more devastating than a typical tsunami. In 1919 the dense wall of syrup surging from its collapsed tank initially moved fast enough to sweep people up and demolish buildings, only to settle into a more gelatinous state that kept people trapped."<ref name=":0" />

The Boston Globe reported that people "were picked up by a rush of air and hurled many feet". Others had debris hurled at them from the rush of sweet-smelling air. A truck was picked up and hurled into Boston Harbor. After the initial wave, the molasses became viscous, exacerbated by the cold temperatures, trapping those caught in the wave and making it even more difficult to rescue them.<ref name="nbc 100" /> About 150 people were injured, and 21 people and several horses were killed. Some were crushed and drowned by the molasses or by the debris that it carried within.<ref name="Buell">Template:Cite web</ref> The wounded included people, horses, and dogs; coughing fits became one of the most common ailments after the initial blast. Edwards Park wrote of one child's experience in a 1983 article for Smithsonian:

Aftermath

Damage to the Boston Elevated Railway caused by the burst tank and resulting flood

First to the scene were 116 cadets under the direction of Lieutenant Commander H. J. Copeland from Template:USS, a training ship of the Massachusetts Nautical School (now the Massachusetts Maritime Academy) that was docked nearby at the playground pier.<ref name="NYTimes1919" /> The cadets ran several blocks toward the accident and entered into the knee-deep flood of molasses to pull out the survivors, while others worked to keep curious onlookers from getting in the way of the rescuers. The Boston Police, Red Cross, Army, and Navy personnel soon arrived. Some nurses from the Red Cross dove into the molasses, while others tended to the injured, keeping them warm and feeding the exhausted workers. Many of these people worked through the night, and the injured were so numerous that doctors and surgeons set up a makeshift hospital in a nearby building. Rescuers found it difficult to make their way through the syrup to help the victims, and four days elapsed before they stopped searching; many of the dead were so glazed over in molasses that they were hard to recognize.<ref name="Smithsonian" /> Other victims were swept into Boston Harbor and were found three to four months after the disaster.<ref name="Buell" />

In the wake of the accident, 119 residents brought a class-action lawsuit against the United States Industrial Alcohol Company (USIA),<ref>Template:Cite web</ref> which had bought Purity Distilling in 1917. It was one of the first class-action suits in Massachusetts and is considered a milestone in paving the way for modern corporate regulation.<ref name="Betancourt">Template:Cite news</ref> The company claimed that the tank had been blown up by anarchists<ref name="DarkTide" />Template:Rp because some of the alcohol produced was to be used in making munitions, but a court-appointed auditor found USIA responsible after three years of hearings, and the company ultimately paid out $628,000 in damages<ref name="Betancourt" /> ($Template:Format price in Template:Inflation/year, adjusted for inflationTemplate:Inflation/fn). Relatives of those killed reportedly received around $7,000 per victim (equivalent to $Template:Inflation in Template:Inflation/year).<ref name="Smithsonian" />

Cleanup

Cleanup crews used salt water from a fireboat to wash away the molasses and sand to absorb it,<ref name="TheHour" /> and the harbor was brown with molasses until summer.<ref name="HistoryChannel" /> The cleanup in the immediate area took weeks,<ref name="YankeeMason" /> with several hundred people contributing to the effort,<ref name="DarkTide" />Template:Rp<ref name="Betancourt" /> and it took longer to clean the rest of Greater Boston and its suburbs. Rescue workers, cleanup crews, and sight-seers had tracked molasses through the streets and spread it to subway platforms, to the seats inside trains and streetcars, to pay telephone handsets, into homes,<ref name="Smithsonian" /><ref name="DarkTide" />Template:Rp and to countless other places. It was reported that "Everything that a Bostonian touched was sticky."<ref name="Smithsonian" />

Fatalities

Detail of molasses flood area:Template:PbTemplate:Numbered list

Name	Age	Occupation
Patrick Breen	44	Laborer (North End Paving Yard)
William Brogan	61	Teamster
Bridget Clougherty	65	Homemaker
Stephen Clougherty	34	Unemployed
John Callahan	43	Paver (North End Paving Yard)
Maria Di Stasio	10	Child
William Duffy	58	Laborer (North End Paving Yard)
Peter Francis	64	Blacksmith (North End Paving Yard)
Flaminio Gallerani	37	Driver
Pasquale Iantosca	10	Child
James J. Kenneally	48	Laborer (North End Paving Yard)
Eric Laird	17	Teamster
George Layhe	38	Firefighter (Engine 31)
James Lennon	64	Teamster/Motorman
Ralph Martin	21	Driver
James McMullen	46	Foreman, Bay State Express
Cesar Nicolo	32	Expressman
Thomas Noonan	43	Longshoreman
Peter Shaughnessy	18	Teamster
John M. Seiberlich	69	Blacksmith (North End Paving Yard)
Michael Sinnott	78	Messenger
<ref name=DarkTide />Template:Rp<ref name="NYTimes1919" /><ref>Template:Cite news</ref>

Causes

The molasses tank prior to its 1919 explosion—exact date unknown

Several factors might have contributed to the disaster. The first factor is that the tank may have leaked from the very first day that it was filled in 1915.<ref>Template:Cite book</ref><ref>Birnbaum, Amy. (2019). The Great Molasses Flood: A bizarre disaster struck one of America's biggest cities 100 years ago. Scholastic News (Explorer Ed.), 81(11), 4.</ref> The tank was also constructed poorly and tested insufficiently, and carbon dioxide production might have raised the internal pressure due to fermentation in the tank. Warmer weather the previous day would have assisted in building this pressure, as the air temperature rose from Template:Convert over that period. The failure occurred from a manhole cover near the base of the tank, and a fatigue crack there possibly grew to the point of criticality.

The tank had been filled to capacity only eight times since it was built a few years previously, putting the walls under an intermittent, cyclical load. Several authors say that the Purity Distilling Company was trying to out-race prohibition,<ref name="PuleoQuote79" /><ref name="YankeeStanley" /><ref name="Silverman" /> as the 18th amendment was ratified the next day (January 16, 1919) and took effect one year later.<ref name="Streissguth" /> An inquiry after the disaster revealed that Arthur Jell, USIA's treasurer, neglected basic safety tests while overseeing construction of the tank, such as filling it with water insufficient to check for leaks, and ignored warning signs such as groaning noises each time the tank was filled. He had no architectural or engineering experience.<ref name="Sohn" /><ref name="nbc 100" /> When filled with molasses, the tank leaked so badly that it was painted brown to hide the leakage. Local residents collected leaked molasses for their homes.<ref name="StraightD" /> A 2014 investigation applied modern engineering analysis and found that the steel was half as thick as it should have been for a tank of its size even with the lower standards they had at the time. Another issue was that the steel lacked manganese and was made more brittle as a result.<ref name="GlobeSchworm" /> The tank's rivets were also apparently flawed, and cracks first formed at the rivet holes.<ref name="Sohn" />

In 2016, a team of scientists and students at Harvard University conducted extensive studies of the disaster, gathering data from many sources, including 1919 newspaper articles, old maps, and weather reports.<ref name="AP-Harv">Template:Cite news</ref> The student researchers also studied the behavior of cold corn syrup flooding a scale model of the affected neighborhood.<ref name="NYT-Harv">Template:Cite news</ref> The researchers concluded that the reports of the high speed of the flood were credible.<ref name="NYT-Harv" />

Two days before the disaster, warmer molasses had been added to the tank, reducing the viscosity of the fluid. When the tank collapsed, the fluid cooled quickly as it spread, until it reached Boston's winter evening temperatures and the viscosity increased dramatically.<ref>Template:Cite news</ref> The Harvard study concluded that the molasses cooled and thickened quickly as it rushed through the streets, hampering efforts to free victims before they suffocated.<ref name="AP-Harv" /><ref name="NYT-Harv" /><ref>Template:Cite journal</ref>

Area today

Molasses Flood historical marker

United States Industrial Alcohol did not rebuild the tank. The property formerly occupied by the molasses tank and the North End Paving Company became a yard for the Boston Elevated Railway (predecessor to the Massachusetts Bay Transportation Authority). It is now the site of a city-owned recreational complex, officially named Langone Park, featuring a Little League Baseball field, a playground, and bocce courts.<ref name="Harris" /> Immediately to the east is the larger Puopolo Park, with additional recreational facilities.<ref name="BHA" />

A small plaque at the entrance to Puopolo Park, placed by the Bostonian Society, commemorates the disaster.<ref name=Ocker /> The plaque, titled "Boston Molasses Flood", reads:

The accident has since become a staple of local culture, not only for the damage the flood brought, but also for the sweet smell that filled the North End for decades after the disaster.<ref name="Smithsonian" /> According to journalist Edwards Park, "The smell of molasses remained for decades a distinctive, unmistakable atmosphere of Boston."<ref name="Smithsonian" />

On January 15, 2019, for the 100th anniversary of the event, a ceremony was held in remembrance. Ground-penetrating radar was used to identify the exact location of the tank from 1919.<ref name="Results of Geophysical survey at Langone Park: 100 Years since the Great Molasses Flood">Template:Cite web</ref> The concrete slab base for the tank remains in place approximately Template:Convert below the surface of the baseball diamond at Langone Park. Attendees of the ceremony stood in a circle marking the edge of the tank. The 21 names of those who died in, or as a result of, the flood were read aloud.<ref name="Globe_2019">Template:Cite news</ref><ref name="Universal_Hub_2019">Template:Cite web</ref>

Many laws and regulations governing construction were changed as a direct result of the disaster, including requirements for oversight by a licensed architect and civil engineer.<ref name="nbc 100">Template:Cite web</ref><ref>Template:Cite journal</ref>

In popular culture

• The Darkest of the Hillside Thickets' song "Great Molasses Disaster" is about the flood, and their official music video includes many pictures of the aftermath.<ref>Template:Cite web</ref>
• Canadian metal band Protest the Hero's song "All Hands" from the album Palimpsest is written from the perspective of a victim of the flood. The piano interlude to the song is titled "Harborside", a reference to the harborside tanks in which the molasses was stored. The last lines of the song references the first hand accounts of the aftermath.<ref>Template:Cite web</ref>
• Bostonian comedian and actress Ayo Edebiri, on Late Night with Seth Meyers, passionately spoke about the Great Molasses Flood where she mentions that she was "reduced to tears" talking about the tragedy, where people outside of Boston are far less aware of the event.<ref>Template:Cite web</ref>
• In 2025, a designer card game about the event was announced—"Molassacre: Escape the Flood" was based on the mid-20th century game Mille Bornes.<ref>Template:Cite news</ref>

See also

• List of disasters in Massachusetts by death toll
• List of non-water floods
• Honolulu molasses spill

Further reading

• Template:Cite book

External links

• Boston Public Library. Photos related to the event on Flickr. Many phrases are direct quotes.
• The Great Boston Molasses Flood of 1919, four-minute audio story at The American Storyteller Radio Journal
• Interview with Stephen Puleo, author of the book listed in "Further reading"
• Molasses Flood of 1919Template:Webarchive
• "Scenes in the Molasses-Flooded Streets of Boston", from the Washington Times, January 18, 1919
• 100 years ago, Boston's North End was hit by a deadly wave of molasses (photos)
• The Great Molasses Flood of 1919 was Boston's strangest disaster (story with more photos)