This chapter looks at the construction of Boulder Dam. Franklin Roosevelt explained the dam as a manifestation of the transformations the New Deal had set in motion. “The largest generators and turbines yet installed in this country, machinery that can continuously supply nearly two million horsepower of electric energy,” Roosevelt explained, would soon “power factory motors, street and household lights and irrigation pumps.” In so doing, the dam's energy would transform the region and the nation at large; it would create industrial modernity. Ultimately, the construction of Boulder Dam, and the politics surrounding it, signaled a change. It suggested that efforts to turn the energy of the river to human purposes had begun to tie the fates of Phoenix and the Navajo Reservation together. Indeed, Boulder Dam had begun the creation of a new region.