Los Angeles, as we know it today, was made possible by massive infrastructure projects that provide reliable sources of water to the otherwise semi-arid region. The mastermind behind many of these infrastructure projects in the early twentieth century was William Mulholland, the self-taught engineer who rose through the ranks to become the Chief Engineer and General Manager of the Bureau of Water Works and Supply (the precursor to today’s Los Angeles Department of Water and Power). Mulholland is most commonly remembered for the construction of the Los Angeles Aqueduct, which piped water to the city from the Owens Valley, over 200 miles away. But Owens Lake was drying up faster than expected, and the aqueduct was threatened by both earthquakes and sabotage from angry landowners and farmers in the Owens Valley who orchestrated dynamite attacks on the waterway, in what became known as the California Water Wars.
Mulholland needed a backup plan, so he turned to building reservoirs, most of which still function to this day. Tom Scott’s video above tells the story of how one of those reservoirs, and the failure of the dam that held it back, shaped the development of Los Angeles itself. When the St. Francis Dam collapsed in 1928 the ensuing rush of water killed at least 450 people (though some estimate the total is closer to 600), destroyed 1,200 homes, forever altered the reputations of Mulholland and the city’s water infrastructure, and ultimately cemented the boundaries of the city and its neighbors.