The Boston Molasses Flood
In January 1919 the North End of Boston, Massachusetts was inundated by a wave of molasses which reached a height of 25 feet at its peak, and moved through the streets of the neighborhood at speeds which reached 35 miles per hour. The Atlantic Avenue elevated train tracks were damaged when the molasses hit its support girders with sufficient force to bend them, derailing a car. Several buildings were forced from their foundations. Men and animals – Boston still being filled with horses at the time – were literally stuck in the molasses, and died from suffocation. As in quicksand, the harder they struggled the more difficult it was to extricate themselves.
There were over 150 people injured by the molasses and the debris which flew in the rush of air which accompanied it. At least 20 people were killed. Many of the dead were covered in a molasses glaze which rendered them unrecognizable. Rescuers searched for casualties from the flood for four days. The streets were cleaned using salt water pumped by fireboats in Boston Harbor. The harbor remained a murky brown color for months after the flood. Rescue and cleanup workers helped spread the molasses throughout the city, tracked by shoes and clothes, and Boston was a sticky town for a long time.
The flood was caused by the failure of a storage tank containing about 2.2 million gallons of molasses which was being fermented to produce ethanol. The tank was owned by the Purity Distilling Company. The fifty foot tall fermentation tank had been leaking for some time, rather than repair the tank the company painted it brown to hide the leaks. It was later learned that the tank was constructed of steel too thin to withstand the pressure from contents when full. The tank had been filled to different levels throughout its use history, creating varying stresses on the too brittle steel.
The day before the disaster the tank had been filled to near capacity, and the fermentation process created carbon dioxide which increased the pressure within. Poorly designed and inadequately maintained, the tank burst apart near a manhole cover, where stress cracks yielded to the pressures within the tank. Just two days earlier molasses had been added to the tank, warmer than what was already stored, which made the whole more fluid. After the tank ruptured the molasses at first spread quickly until the colder Boston temperatures made it thicken, which slowed its movement and made it more difficult to extricate victims.
The Great Molasses Flood led to one of the earliest class action lawsuits in Massachusetts history. The United States Industrial Alcohol Company – owner of Purity – paid $600,000 to claimants through an out of court settlement after claiming that the tank had been the target of saboteurs. The tank and the Purity offices, which had been flattened in the flood, were not rebuilt and the land was used as a railyard by the Boston Elevated Railway. Today the area is owned by the City of Boston and is used as a park, with the site of the disaster marked by a commemorative plaque.
Where do we find this stuff? Here are our sources:
“Run for your lives”, by David McCullough, American Heritage Magazine, June 1966
“Tacoma Narrows Bridges”, by Henry Petroski, American Scientist, 2009
“Man-Made Disaster: The Story of Saint Francis Dam”, by Charles F. Outland, 2002
“Disaster echoes 140 later (sic) Bridge collapse ended, altered many lives; hurt Ashtabula’s growth”, by Dave Deluca, Ashtabula Star Beacon, December 29, 2016
“Cadillac Desert”, by Marc Reisner, 1993
“Hyatt skywalks collapse changed lives forever”, by Kevin Murphy, Kansas City Star, July 9, 2011