Hoover Dam was America's shining light during the dark days of the Great Depression. This monumental structure was the largest federal works project of its time, constructed after years of scientific study and political maneuvering by California boosters. This thirsty state looked to the untapped Colorado River to supply reliable water for Imperial Valley farms and the fast-growing Los Angeles metropolitan area. Harnessing the unruly Colorado River would be no easy task. Only the federal government could fulfill the dream. An unprecedented high dam, over 700 feet tall, was designed to store two years of river flow, trap tons of silt, and gain control of the river. The project was financed by the sale of hydroelectric power to southern California, Arizona, and southern Nevada. Today, Imperial Valley is an American garden spot, and Los Angeles is one of the nation's most influential cities. The Las Vegas Valley also witnessed tremendous growth beginning with the dam and followed by legalized gambling, defense industries, and tourism. Meanwhile, the small town of Boulder City, born during the dam's construction, still thrives in the shadow of Hoover Dam.