In the early part of the 20th century, the U.S. Bureau of Reclamation began an ambitious project that entailed constructing a huge dam on the Arizona-Nevada border to tame the Colorado River and thus supply the fast-developing Southwest with water and hydroelectricity. The finished product, Hoover Dam, completed in 1935, was a monumental task unto itself; workers survived carbon monoxide-ridden tunnels and dizzying heights of up to 800 feet.
Although it was earlier projected as the Boulder Canyon project, the site of the dam was subsequently changed to Black Canyon. Considering the controversies over its cost estimate of $165 million and apportioning its water between seven states, a compact that has been called the Colorado River Compact was forged by the Secretary of Commerce Herbert Hoover in 1922, providing equal allotments of water apiece. The outgoing President Calvin Coolidge officially authorized the project in December 1928, and the dam was named for Herbert Hoover in 1930, though the name was not officially recognized until 1947.
The Great Depression brought a wave of optimistic workers to Las Vegas and many of them made their way further east to Boulder City, a town designed specifically for the workers on the dam. The construction contract was let to Six Companies in March 1931. Preliminary work consisted of dynamiting canyon walls to accommodate diversion tunnels, a very dangerous operation, and on August 1931 conditions became so bad that a strike for humane working conditions lasted six days.
Other dangerous processes in construction included clearing canyon walls for the dam by suspending high scalers to knock loose material from great heights. The dried bed of the river exposed ways for the building of the power plant, intake towers, and the dam itself. Almost 600 miles of pipe loops were embedded for on-site cement mixing and transportation across the canyon via cableways to circulate water and cool the concrete.
Designer Gordon Kaufmann had taken the stark mass of the dam and covered it in a smooth, parabolic face devoid of ornament. The powerplant reflected a sense of futurism, its horizontal windows sheathed in aluminum fins, its interior a celebration of Native American culture.
By 1935, the dam rose 726 feet above the canyon floor. President Franklin Roosevelt celebrated the completion on September 30, 1935, with a crowd of 20,000 in attendance. The dam needed some 5 million barrels of cement and 45 million pounds of reinforcement steel–enough concrete to pave a road from San Francisco to New York City. A workforce of around 21,000 contributed to its construction.
The Hoover Dam revolutionized the Southwest, facilitating the growth of major cities such as Los Angeles, Las Vegas, and Phoenix. Its 17 turbines produce enough electricity to power 1.3 million homes, and it was declared a National Historic Landmark in 1985 and one of America’s Seven Modern Civil Engineering Wonders in 1994. The dam draws some 7 million visitors each year, while Lake Mead, the world’s largest reservoir, claims another 10 million as one of the most popular areas in the nation for recreation.
The name itself, for the dam, was contentious because of its first and earlier proposed site named Boulder Dam. Then, in 1930, U.S. Secretary of the Interior Ray Lyman Wilbur announced it would be called Hoover Dam. With some political shifts in power, the name briefly reverted to Boulder Dam. Only in 1947 did President Harry Truman officially approve Hoover Dam as its name.
Boulder City was built to accommodate the workers for the dam and was a peculiar town wholly controlled by the federal government, with prohibition on alcohol among other things, and no gambling. The city also hosted dignitaries and famous figures during the construction of the dam.
The largest man-made reservoir in America, made by the damming of the Colorado River, Lake Mead is 248 square miles in size, with an accumulated capacity of 28.9 million acre-feet of water. This serves as a supplier of water to farms, businesses, and millions of people in Nevada, Arizona, California, and Mexico. However, it has faced significantly reduced water levels as a result of the prolonged drought period.
Contrary to popular myth, no workers were buried alive in the dam’s concrete. The project employed 21,000 men, with an average of 3,500 working daily. The construction was dangerous, with 96 official fatalities, though some sources suggest the number was higher.
Hoover Dam was completed to stand the world’s tallest dam at 726.4 feet. This distinction went to the Northern California’s 770-foot-high Oroville Dam. The installed capacity of 2,080 megawatts made the power plant in this dam the world’s largest hydroelectric station from 1939 to 1949.
During World War II, the German plot to bomb Hoover Dam included targets that would damage Southern California’s aviation manufacturing industry. Due to very tight security by U.S. officials, private boats were banned in Black Canyon, while lights and physical barricades were added in the dam itself. Visitors were no longer allowed into the dam for the remainder of the war.
Eventually, this was achieved in 2010, when the Mike O’Callaghan-Pat Tillman Memorial Bridge was completed, which diverts traffic away from across the top of the dam. The bridge is nearly 900 feet above the Colorado River and is the longest single-span concrete arch bridge in the Western Hemisphere, the second highest in America.
Hoover Dam remains a symbol of American engineering prowess and strategic importance, still playing an important role in the development of the Southwest and infrastructure.