October 9, 1936: Hoover Dam Begins Transmitting Electricity to Los Angeles

On October 9, 1936, electricity generated by the massive Hoover Dam began flowing across the deserts and mountains of the American Southwest to Los Angeles, California. Traveling over transmission lines stretching approximately 266 miles, the electricity helped power the city's lights, radios, appliances, and businesses. The milestone demonstrated the enormous potential of one of the greatest engineering achievements of the 20th century and helped fuel the continued growth of the American West.

Hoover Dam had been constructed during one of the most difficult periods in American history. Work began in 1931, as the Great Depression left millions of Americans unemployed. Thousands of workers and their families traveled to Nevada in search of jobs on the ambitious federal project. Building a dam across the Colorado River required crews to work in extreme desert heat and dangerous conditions as they blasted canyon walls, diverted the river, and poured enormous quantities of concrete.

The dam was originally known as Boulder Dam, although its name became the subject of political debate. Construction began during President Herbert Hoover's administration and was completed during President Franklin D. Roosevelt's presidency. The structure was dedicated by Roosevelt in September 1935, and the name Hoover Dam was officially restored by Congress in 1947.

At the time of its completion, Hoover Dam was the tallest dam in the world. Rising more than 700 feet above its foundation, the massive concrete structure represented a remarkable achievement in engineering and construction. Yet producing electricity was only one of the reasons for building it.

For generations, communities throughout the Southwest had struggled with the unpredictable Colorado River. The river could bring destructive floods in some years and insufficient water in others. Hoover Dam allowed the federal government to regulate the river while storing enormous quantities of water in Lake Mead, the reservoir created behind the dam. That water could then be distributed to growing cities, farms, and communities throughout the region.

Hydroelectric power became another major benefit. Water passing through the dam's turbines generated electricity that could be transmitted to communities hundreds of miles away. When power began reaching Los Angeles on October 9, 1936, it provided a dramatic example of how the Colorado River could support the rapidly expanding population and economy of Southern California.

The dam's influence extended far beyond Los Angeles. Its water and electricity helped support cities, agriculture, and industry across the Southwest, contributing to the remarkable development of places such as Southern California, Nevada, and Arizona. At the same time, managing the Colorado River has become increasingly challenging as the region's population has grown and water supplies have faced greater pressure.

Nearly a century after its construction, Hoover Dam remains an enduring American landmark. The electricity that began traveling toward Los Angeles on October 9, 1936, marked another chapter in the transformation of the West and demonstrated how an enormous public works project could reshape the future of an entire region.