Concrete, steel and turbines play an outsize role in the past and future of water in western states. The evolution of the sprawling cities of the American West is inextricably bound to America’s 20th-century fascination with dam-building. But that decades-long story, rife with dammed and diverted rivers as well as political intrigue, is being reshaped by climate change, drought and overuse into a tale of ecologic and economic misadventure. Despite the problematic history of the big dam projects, however, historian Char Miller insists that objective assessment requires acknowledgment of both the benefits these structures have provided and the good intentions involved in their creation.