How the Great Molasses Flood Devastated Boston in 1919

On a chilly afternoon in January 1919, an unusual and catastrophic disaster swept through the streets of Boston’s North End. A 2.3 million-gallon storage tank of molasses, used for manufacturing industrial alcohol, suddenly ruptured, unleashing a sticky tidal wave that would go down in history as one of the strangest industrial accidents ever recorded. This bizarre yet tragic event, now remembered as the Great Molasses Flood, claimed lives, destroyed property, and reshaped safety regulations in the city.

The Build-Up to Disaster

The tank that housed the molasses belonged to the Purity Distilling Company, which used the sticky substance in alcohol production. Built hurriedly in 1915, the tank had structural flaws from the start. It frequently leaked, with locals often seeing molasses oozing from its sides—a sight the company attempted to obscure by painting the tank brown.

Despite warnings and visible signs of weakness, little was done to reinforce the structure. On January 15, 1919, temperatures had warmed unusually after a cold spell, which may have increased internal pressure within the poorly constructed tank.

The Day of the Flood

At approximately 12:30 p.m., the tank burst open with a thunderous roar. Witnesses described hearing sounds like machine gun fire as rivets shot out from the tank. A massive wave of molasses, estimated at 25 feet high and moving at 35 miles per hour, surged through the streets.

Buildings were crushed, steel girders from an elevated train line were bent, and people and horses were swept off their feet. The viscous nature of molasses made escape nearly impossible for those caught in the wave.

The Human and Economic Toll

The disaster claimed 21 lives and injured around 150 people. Rescue efforts were chaotic as first responders struggled to navigate the sticky, treacherous environment. Victims suffocated, drowned, or were crushed by debris. Cleanup operations lasted for months, with molasses tracked throughout the city on shoes and vehicles.

In the aftermath, survivors described the air reeking of molasses for years.

Legal and Regulatory Changes

The catastrophe led to one of the first major class-action lawsuits in U.S. history. The investigation revealed that the tank’s failure was due to shoddy construction and inadequate testing. The Purity Distilling Company was found liable and ordered to pay substantial damages.

This disaster prompted changes in construction standards and safety regulations, including stricter oversight of industrial storage facilities.

Legacy of the Molasses Flood

The Great Molasses Flood remains a unique chapter in American history—a surreal yet sobering reminder of the consequences of corporate negligence and poor engineering practices. Though often recounted with a sense of disbelief, it stands as a testament to the importance of safety and accountability.

Today, Boston’s North End thrives as a historic neighborhood, but the story of the flood continues to be retold as both a quirky piece of history and a cautionary tale.