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VOICE ONE: This is Bob Doughty. VOICE TWO: And this is Steve Ember with EXPLORATIONS in VOA Special English. Today we tell about Hoover Dam. It was the largest and most difficult structure of its kind ever built when work started in nineteen thirty-one. VOICE ONE: Our report today about Hoover Dam must begin with the Colorado River. This river made the dam necessary. The Colorado River begins high in the Rocky Mountains. It begins slowly, during the dark months of winter. Heavy snow falls on the Rocky Mountains. The snow is so deep in some areas that it will stay on the ground well into the hot days of summer. But the snow does melt. Ice cold water travels down the mountains and forms several rivers -- the Gila River, the Green River, the Little Colorado, the San Juan, the Virgin and the Gunnison rivers. These rivers link together and form the beginnings of the Colorado River. The Colorado River flows through, or provides water for, the states of Wyoming, Colorado, Utah, New Mexico, Arizona, Nevada and California. Then it crosses the border into Mexico. VOICE TWO: The Colorado River has always been extremely powerful. The river created the huge Grand Canyon. The violent water cut hundreds of meters deep into the desert floor of Arizona. The Grand Canyon is proof of the power of this great river. The Grand Canyon was cut into the desert floor beginning thousands of years ago. But the power of this river has been demonstrated in more modern times. Between nineteen-oh-five and nineteen-oh-seven, the Colorado River caused great amounts of flooding in parts of Arizona and California. Huge amounts of water ran into a low area in the dry, waterless desert that had once been an ancient lake. In two years of flooding, the Colorado River filled the ancient lake. That lake is called the Salton Sea. Today, it is about fifty-six kilometers long by twenty-five kilometers wide. It is even larger in years of heavy rain. VOICE ONE: The flooding that created the Salton Sea also flooded homes, towns and farming areas. Many people were forced to flee their homes. Government leaders knew they had to do something to prevent such floods in the future. In nineteen eighteen, a man named Arthur Davis proposed building a dam to control the Colorado River. Mister Davis was a government engineer. He said the dam should be built in an area called Boulder Canyon on the border between the states of Arizona and Nevada. VOICE TWO: Building the dam would not be a simple matter. The people of seven states and the people of Mexico needed and used the water of the Colorado River. Much of that area is desert land. Water is extremely important. Without water from the Colorado River, farming is not possible. Without water, life in the desert is not possible. On November twenty-fourth, nineteen twenty-two, officials signed a document in Santa Fe, New Mexico. That document is called the Colorado River Compact. The document tells how the seven states would share the water of the Colorado River. It was agreed this could be more easily done with the aid of a dam. Later an agreement was signed with Mexico to supply it with water from the Colorado River. Source: Voice of America