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VOICE ONE: The area chosen for the dam was called Black Canyon. The walls of Black Canyon rise almost two hundred forty-three meters above the river. An ancient volcano formed the rock in Black Canyon. Engineers decided the rock would provide a good strong support for the proposed dam. However, the area also presented problems. The nearest railroad was sixty kilometers away. There was no electric power. And, in the summer, the temperature in the desert in Black Canyon could reach as high as forty-eight degrees Celsius. A great deal of work was done before operations started on the dam. Workers built a town called Boulder City to house employees working on the dam. They built a large road from Boulder City to the area of the dam. They built a railroad from a main line in Las Vegas, Nevada, to Boulder City. They built another railroad from Boulder City to the dam area. And they built a three hundred fifty kilometer power line from San Bernadino, California. This provided electric power to the area where the dam was being built. VOICE TWO: The work on the dam began in April of nineteen thirty-one. Workers called "high scalers" were some of the first to begin building the dam. They were suspended from ropes as they used heavy air-powered hammers to break any loose rock away from the face of the canyon walls. When they could not use hammers, they used dynamite. One high scaler became very famous. His name was Arnold Parks. He caught another worker who had fallen off the top of the canyon. Mister Parks held the worker to the wall of the canyon until others came to help. Today, visitors can see a statue of the men who worked as high scalers to build Hoover Dam. The high scalers worked on the sides of the canyon. Other workers dug huge tunnels deep in the floor of the canyon. This was done to permit the Colorado River to flow away from the construction area. This had to be done so the floor of the dam could be built. On June sixth, nineteen thirty-three, workers poured the first load of a building material called concrete. Men in two special factories worked day and night to make the concrete building material for the dam. Huge equipment moved millions of tons of rock and sand. In the summer months, the terrible desert heat slowed the work but did not stop it. Men who worked at night on the dam suffered less, but the heat was still as high as thirty degrees Celsius. VOICE ONE: Slowly the great dam began to rise from the floor of the canyon. From the canyon floor it reaches two hundred twenty-one meters high. Workers poured the last of the concrete on May twenty-ninth, nineteen thirty-five. They had used almost four million cubic meters of concrete in the dam. Workers also used more than twenty million kilograms of steel to strengthen the concrete in the dam. VOICE TWO: The work was dangerous for the more than five thousand men who worked on the structure. The extreme temperatures, falling objects and heavy equipment caused accidents. The workers were provided with medical care and two emergency vehicles to take them to a new hospital in Boulder City. However, ninety-six men lost their lives during the building of the great dam. The companies building the dam had been given seven years to complete the work. They did it in only five. The dam was finished on March first, nineteen thirty-six. Other work now began. This work would make the dam into one of the largest producers of electric power ever built. The dam was built to control the powerful Colorado River. But it was also meant to use the river to produce large amounts of electric power. Today, seventeen huge machines use the river's power to produce electric power. The states of Arizona and Nevada share the power. So do many cities in California, including Los Angeles, Burbank and Pasadena. VOICE ONE: When the Hoover Dam was finished in nineteen thirty-six, it was the largest dam in the world. It was also the tallest. And it was the largest power producer that used water power to make electricity. Today this is no longer true. Taller dams, larger dams and a few that produce more power have been created. But Hoover Dam is still a huge and interesting place. Visitors to Hoover Dam drive on a small road that passes Lake Mead. They enter a special visitors' center to learn about the dam and the men who built it. They ride high-speed elevators that go deep inside the dam. They see the huge machines that produce electric power. Many visitors say they thought the name of the huge structure was Boulder Dam. They are told that Hoover Dam is often called Boulder Dam. However, it is named after former President Herbert Hoover. Before he was president, Mister Hoover worked for many years to make the construction of the dam possible. It was officially named to honor him in nineteen forty-seven. Visitors leave the great dam with an understanding of how difficult the project was. They learn that it still safely controls the great Colorado River. And it also provides water and electric power to millions of people in the American southwest. VOICE TWO: This program was written by Paul Thompson. It was produced by Mario Ritter. This is Steve Ember. VOICE ONE: And this is Bob Doughty. Join us again next week for another EXPLORATIONS program in VOA Special English. Source: Voice of America