The 1928 St. Francis dam disaster in Los Angeles, California is one of the most devastating man made failures in the history of the United States. It came down in the history of the state as the second greatest loss of life with the first one being the 1906 San Francisco earthquake. The dam was engineered under the supervision of William Mulholland who, at the time, was a manager at the Los Angeles Bureau of Water Works and Supply. Built 40 miles northwest of Los Angeles, St. Francis dam was providing water for the Los Angeles–Owens River aqueduct water reservoir. The dam was supposed to be vital to the city’s water infrastructure. Back in the day, the population of Los Angeles was growing rapidly, reaching 320,000 people in 1910 and almost doubling by 1920 (Hundley et al., 2016). The increased demand for water supply was putting pressure on the civil engineering bureaus of the state.
Two years after the end of its construction, on the night of March 12, 1928, the St. Francis Dam collapsed. The failure gave way to more than 12.4 billion gallons of water that rushed freely to the San Francisquito Canyon (Hundley et al., 2016). The height of the water wall reached 140 feet, and the torrents traveled 54 miles down before coming to a full stop. Among the towns affected by the disaster were Castaic Junction, Fillmore, Bardsdale, and Piru. The water destroyed 1,000 houses and claimed between 450 and 600 lives (Hundlet et al., 2016).
Soon after the collapse, an investigation started and many shocking discoveries were made. It became obvious that St. Francis dam was poorly designed and engineered from the very beginning, and its failure was bound to happen sooner or later. The experts pointed out plenty of faults, starting with the chosen location. The dam was built on a landslide, and at one point, its height was increased without adding to its width for more stability (Hundley et al., 2016). The investigation also revealed that the dam had several leaks and cracks that were either ignored or poorly repaired. It is not impossible that repairs made the dam even more hazardous and unstable. Two weeks before the disaster, the dam keeper reported muddy leaks from below the abutments, which implied the erosion of the fundament. Mullholland came for inspection, acknowledged the risks, and concluded that corrective measures could be taken some time in the future.
The blame fell on the chief engineer William Mullholland who was in charge at all stages of construction. However, some evidence suggested that Mullholland was trying to warn the members of the Board of Public Works of the dangerous schist on the eastern side of the canyon. Eventually, the warning was ever misinterpreted or dismissed by the supervisor of St. Francis Dam, Stanley Dunham (Hundley et al., 2016). Eventually, the chief engineer was cleared of all charges, but the failure was the end of his otherwise successful career as a civil engineer. St. Francis Dam collapse was ascribed to a series of human errors and engineering misjudgment of the situation.
Probably, the most important lesson to learn from the St. Francis dam failure is that to err is human. At the final stage of criminal investigations into a Mullholland’s case, Los Angeles County’s Coroner sent his often-cited inquest. He argued that the construction of the dam should have never been a sole responsibility of one man (Hundley et al., 2016). People make mistakes, which is why undertaking large projects requires the joint effort of many experts and professionals as well as independent peer reviews.
Reference
Hundley, N., Jackson, D. C., & Patterson, J. (2016). Heavy Ground: William Mulholland and the St. Francis Dam Disaster (Vol. 8). Univ of California Press.