January 15, 1919
Around lunchtime, as the citizens of Boston gathered to enjoy their midday meal, madness overtook the city. A giant tank of molasses had burst open on the town’s north side, unleashing over two million gallons of thick, sticky liquid that raced down the blocks at speeds up to 35 miles per hour. Streets were flooded, buildings were smashed, and horses became trapped in the substance. 21 people were killed; over 150 more were injured. According to residents and visitors alike, the smell was just as sticky, lingering in the city for decades after. In the tragedy’s wake, some media speculated that fermentation had increased pressure in the tank, setting off an explosion. The trial lasted for years, eventually reaching 20,000 pages of conflicting testimony and witness input. However, U.S. Industrial Alcohol, the company with ownership over the busted tank, was found liable, and modern investigations have found several factors for the tank’s explosion.
Research points to the tank’s structure as a fundamental issue. It was 50 feet tall and 90 feet in diameter, with a capacity of 2.5 million gallons. However, the steel walls, which were only 0.67 inches at their thickest, were too thin to support full capacity. Stress also became high on the rivet holes, where the cracks were found to have first formed. The USIA was aware of these warning signs, yet, to satisfy the desire for industrial alcohol during World War I, they continued to use the container. Employees noted loud groaning sounds each time the tank was filled and obvious cracks along the side that dripped molasses. City children would even bring cups to fill with the sticky substance. Issues in the foundation were clear from the start, yet they were ignored.
Though molasses is roughly 1.5 times denser than water, making it slow to pour, the initial wave moved close to 35 miles per hour. Fluid dynamics made the liquid more like ketchup, causing it to wreak havoc like a mudslide. Additionally, the day’s mild temperatures made it easier for the molasses to spread. By the time temperatures dropped, it had overtaken roughly two blocks, with a depth of a foot in some places. To make matters worse, chilly air conditions trapped victims in the hardening substance. Mere hours afterward, at least one person was dead by asphyxiation. Historians and scientists alike speculate that rescue efforts would’ve been much easier had the accident occurred in the heat of summer, allowing the molasses to spread further. A thinner, warmer covering would’ve made it much easier to pull individuals out.
Ultimately, at the end of the day, the issue of the Great Molasses Flood boils down to both conditions and negligence. Looking back, it becomes obvious that the tragedy could’ve easily been avoided had the safety of the public taken priority over business in the eyes of the USIA.
