Transcript for Hoover Dam Construction, segment 16 of 17


Equipped with cylindrical gates which function as giant valves, the four intake towers serve as inlets to the four steel penstocks, supplying water to the turbines and outlet valves. Perched on shelves hewn into the canyon walls, they tower four hundred and three feet to an elevation above the crest of the dam and the rim of the canyon. With a combined capacity of four hundred thousand cubic feet of water per second, the two spillways located one on each side of the canyon upstream from the dam will serve as high level controls once the water of the reservoir has risen to its maximum storage elevation. Each spillway is equipped with four one hundred foot drum gates acting through a vertical dimension of sixteen feet. Water flowing over the lowered gates into the spillway basin plunges six hundred feet down through the tunnels to reenter the river downstream from the dam.

The Boulder Dam power plant is built in two wings, one along each side of the canyon wall at the downstream toe of the dam. The first generator was placed in operation on September eleventh, nineteen thirty-six. Equipped with seventeen generating units with capacities ranging from forty thousand to eighty-two thousand five hundred kilovolt amperes, this, the world's largest power plant, is capable of generating one million eight hundred and thirty-five thousand horsepower of electrical energy when operating at its rated capacity.

The transmission lines carrying Boulder Dam power radiate in a network from the dam with the major lines serving the Los Angeles metropolitan area. From the takeoff structure located on the roof of the powerhouse, the lines are taken up over the rim of the canyon into the switchyard above where the most highly specialized and modern development in the power transmission field are to be found.

From the switchyard, the lines travel out across the desert bringing light to the homes and cities and power to the factories of the great southwest. From Parker Dam, one hundred and fifty miles to the south, the Colorado River Aqueduct supplies the city of Los Angeles with the domestic and industrial water supply, while from the Imperial Dam, three hundred miles to the south, the All-American Canal diverts water from the Colorado River into the rich agricultural districts of the Imperial Valley.