The 20th century dawned with both excitement and concern for the water future of California and the rapidly growing but arid American West. Gold fever was receding, urban populations were burgeoning, and tentative efforts at modern, irrigated agriculture were expanding. The articles in this Scientific American collection reveal beliefs common at the time: Any water flowing unused to the sea was wasted. Growth of the West could happen only through expansion of irrigated agriculture and a blossoming of the desert. And there was no water problem that American engineering could not solve.

These articles are paeans to technical know-how and to an indomitable will to satisfy pressing water needs in the face of a hostile and unforgiving environment. Many are written by the pioneering engineers and designers of California’s most remarkable water projects themselves. There seems never to have been any question in their minds that the necessary resources would be harnessed and all economic, natural and political obstacles eventually overcome. The alternative—limits and constraints on the economy of a powerful new nation—was anathema. Projects would be “built out of grim necessity—to meet the demands of a population that had increased beyond reasonable belief, and of industries that cried aloud for assistance,” wrote Edgar Lloyd Hampton in a 1927 Scientific American article about diverting water from the Colorado River over mountains to quench Los Angeles’s growing thirst. That the government could fail to support water development in the West was “as inconceivable as the thought that it might repudiate its Liberty Bonds, or its legal tender,” he noted in that heady era.

And they succeeded. The projects described here—including the Los Angeles, Hetch Hetchy and Colorado River aqueducts, the Central Valley and State Water projects, Boulder and Parker dams, and others—form the backbone of our life in arid lands. They are documented with pride in engineering prowess and the repeated use of superlatives: “unprece­dented,” “largest,” “longest,” “gigantic,” “titanic” and “without a comparable parallel in modern engineering.” Cities such as Los Angeles, Denver, San Francisco and Las Vegas survived and prospered far beyond the limits of their local water resources. Agriculture west of the Mississippi River expanded to tens of millions of acres that could not support crops without artificial irrigation. And cheap hydroelectricity powered the development of industry.

Today the wild rivers of the West have been tamed, channeled, stored, diverted and consumed. The San Joaquin River, which once fed the largest inland estuary in the western U.S., is now one of the nation’s most endangered rivers, entirely used up for agricultural and urban needs and leaving behind nothing but trickles of agricultural runoff and waste. The Colorado no longer reaches its delta.

And the West’s water problems persist. Read carefully: even in these pieces, there are hints—in what the authors say and do not say—of the challenges we still face today.

Writing in 1890, William Hammond Hall—the first State Engineer of California and an early commenter on Western water policy—lamented the lack of knowledge, organization and capital being invested to capture and best use the waters of California. In 1900 the U.S. Department of Agriculture published a report that sounds eerily like what we hear in 2014, highlighting the lack of “diversified farming,” “unwise investments,” “overappropriation of streams” and “absolute private ownership of water.” This report concluded that “the whole system is wrong … wrong in principle as well as faulty in procedure” and called for reform:

“The reform of the irrigation laws of California involves the future of a great commonwealth. The possibilities which wait on success and the evils which will surely attend failure ought to enlist the efforts and intellects of the ablest and best men in the State.”

This was a time when society largely did not know, understand or care much about the environment—despite the glimmerings of the environmental movement in the strong opposition to the Hetch Hetchy–San Francisco water system from John Muir and the recently formed Sierra Club. Not a single article from the early part of the 20th century comments on the ecosystem values of Western water, or the extent of the Pacific Flyway for birds, or the effects of dams and reservoirs on free-flowing rivers. In the 1905 article outlining the first plans to build the Los Angeles Aqueduct was a story on the salmon fisheries of the Northwest, focused on how to effectively catch and kill more fish. Yet these same water projects helped to drive many West Coast salmon runs to, or over, the edge of extinction.

Things are changing again. Continued population growth, diminished public funding, absolute “peak water” limits to renewable water supplies, and accelerating climate changes herald new political conflicts. Existing dams, aqueducts and groundwater wells continue to provide great benefits to cities and industrial agriculture. But the limits of traditional water infrastructure to provide new sources of water are apparent, in the form of ecological devastation, an escalating public environmental movement and higher costs to consumers.

We need new thinking and new solutions: from treating water as a resource to be exploited solely for human benefit to the realization that sustainable use of water must address human and ecosystem needs together.

We now know that water flowing to the sea is not wasted but that it contributes to valuable ecological services. Traditional engineering infrastructure is now supplemented by other kinds of technology, including satellite observation systems, soil-moisture monitors, drip irrigation, smart meters, efficient appliances, advanced desalination, and urban water recycling and reuse. We know that a sustainable water future includes rethinking economics and water management institutions. The articles in this collection remind us both to celebrate our past science and engineering marvels and to look to a more sustainable future as technology, perception, social values and understanding keep evolving.

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