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Los Angeles and San Francisco, with nearly 20 million residents in their combined metropolitan areas, are California’s two most famous cities. Yet neither city has anything close to an adequate water supply within hundreds of miles. Tremendous feats of hydraulic engineering are necessary to store and transport water from California’s inland mountain rivers to big cities on the state’s semi-arid coast. In the early twentieth century, a pair of Irish immigrant engineers named Bill and Mike took charge of building these water systems for Los Angeles and San Francisco. William Mulholland (“Bill”) was a self-taught school dropout whose projects bringing water to Los Angeles were grand in scale, yet simple in design, and in one case, fatally flawed. Michael M. O’Shaughnessy (“Mike”) was an academically trained, properly credentialed, and highly experienced engineer before he took over the design and construction of San Francisco’s water system. The work of these two Irishmen made it possible for their adopted cities to keep growing, but at the expense of two scenic valleys that were despoiled in the name of urban progress. The careers of Bill and Mike demonstrated the value of professional training and expertise over amateur autodidacticism, but also the irony of the sort of water imperialism they practiced. The more water they appropriated for their cities, the more people moved into those cities, raising demand faster than supply. Today, even as their populations decline, Los Angeles and San Francisco face greater water challenges than ever due to drought, climate change, and the sort of environmental concerns that Bill and Mike could never have imagined.


California, Water, Dams, Aqueducts, Los Angeles, San Francisco, Hetch Hetchy, Owens River Valley, water wars, Mulholland (William), O’Shaughnessy (Michael Maurice), Irish Immigrants, 20th century, History


This article originally appeared in Siècles, Volume 53, 2023. The article can also be found online at:

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This work is licensed under a Creative Commons Attribution 4.0 License.