Hoover Dam extends 30 miles southeast of Las Vegas along Colorado River in Black Canyon between Arizona and Nevada. “The dam construction took place in the1930s, with the concrete arch-gravity structure intended to prevent flooding, provide water for hydroelectric power and irrigation for the drier states of Arizona and Califonia.”1 Hoover dam was originally referred to as Boulder Dam, but was later renamed in the honor of Herbert Hoover, who was U.S. secretary of commerce in 1947.The 31st U.S. president proved influential in getting the dam constructed. The height of the dam is 726 feet, and it is 1,244 feet long, which made one of the largest man-made structures and the leading in the production of hydroelectric power in the world when it was constructed. Five million tubs of concrete were utilized in the dam construction.
The original plan to build the dam was in 19th century to provide irrigation and allow for settlement in the arid Southwest. In 1905, melting of snow resulted into massive flooding completely covering nearby farms. “Following the massive flooding, Arthur P. Davis, in the year 1922sketcheda project plans for the construction of the great hoover dam.”2The massive building project was started in 1931 by Six Company, Inc. a combination of six companies as the bottommost competent bidder at $48,890,955. About 21,000 coupled with the intelligence of more than 200 engineers who endured extremely severe working conditions and dangerous dangers to ensure the completion of Hoover Dam.
The architectural design and engineering team developed steel solid rib that is appropriate for gorge crossing. The solid rib configuration is a wharfs and a geometric blend of piers dock system and arch ribs, rising 2015 feet long. Water from the river was diverted to flow through tunnels prior to the building of the arch-gravity dam.
. Billington, D and Martin V. Melosi. The history of large federal dams: planning, design, and construction of big dams, 2005 (49).
2.Stevens, Joseph E. Hoover Dam: an American adventure. Norman: ( Oklahoma University Press, 1990), 78.
Forty-four thousand tons steel was joined into 14,800f pipers that varied in diameter with each length of wider pipes being 12-30 feet. A concrete solid rib, which is a twin rib box girder, was necessary for a longer span and elevation.
Hoover Dam generated an artificial lake called Lake Mead. “The water flowing from the lake provides energy for the generation of hydroelectric power. There is use of generators and turbines in the conversion of water current, which give mechanical energy to electrical energy. Mechanical energy from water is gained from the force of water flowing from Lake Mead, downstream through penstock. Water flowing from the paddocks is directed to the scroll case, where the water hits and spins turbines”3.
Hoover Power plant has seventeen turbines; eight and nine on the Nevada and Arizona wing respectively. The turbines that are connecting the shaft are rotated by the water current that in turn put the generator in motion. In the generators, electromagnetic charges are generated by applying direct current to copper wiring “stator”4 attached to the assembled magnetic steel. The steel poles are positioned on the edge of the rotor and are joined to the revolving turbines. Electric power is produced by the magnets as the rotors revolve past the stationary wiring of the stator; electricity generated is transmitted through the generator’s output centers. “The generators are housed within a protective structure, and their stored energy can be fed into power lines. Through the process, electrical energy is generated by the turbines and generators propelled by the mechanical energy from water current.”5 Hoover Dam produces an average of 4 billion kilowatt-hours of hydroelectric power annually that is consumed in California, Nevada, and Arizona.
The water that has been used to turn the water turbines used to produce electricity, the water then flows downstream and get stored in the dam to prevent it from joining Colorado River.
The dam has several advantages, first as a National Historic Landmark. “Hoover Dam draws some seven million tourists annually, with over 10 million others visiting Lake Mead. The tourists come for boating, fishing, sailing, and other recreation activities. The activities create job opportunities and boost the country’s economy”6. Hoover Dam was constructed on multi-purpose basis. It helped control the flooding along river Colorado as it drains into California gulf. The water-flow was improved to provide water to the fertile, but dry agricultural lands of Arizona and California. The water contributes to improving agricultural production and hydroelectric power generation to satisfy the demands of Americans in the adjacent area. Lake Mead (created by the Hoover Dam) supply 84% of Las Vegas’ water demands. “The reservoir behind Hoover dam has also formed new wildlife habitats. In the year 1985, over Two thousand five hundred bird’s species were identified along the shores of the river”7.
Apart from the benefits the dam has, it also has a consequence such as the migration of the indigenous communities living along Colorado River. “There is loss of species through the disruption of the delicate balance of nature in the desert through clearing of large forest areas and changing the local wildlife habitat.”8 Loss of organism habitats threatens the livelihood of local endangered species such desert tortoises and the aquatic species such as the salmon. Deposition of sediment in the delta of California gulf has transformed the environment of the area to the point that wildlife, such as birds, and deer, have begun to disappear. Sediments have “inundated environment alterations and degradation”9 as significant portions of the land is washed down by Colorado River and collects behind the barriers, hence reducing the fertility of floodplains downstream and causing erosion of Colorado River banks.
Billington, David P., Donald C. Jackson, & Martin V. Melosi. The history of large federal dams: planning, design, and construction in the era of big dams. Denver, Colo: U.S. Dept. of the Interior, Bureau of Reclamation, 2005
DuTemple, Lesley A. The Hoover Dam. Minneapolis: Lerner Publications Co.,2003)
- Ray L & Elwood M, The construction of hoover Dam (NY: Knopf, 1990) 24
- Lower Colorado region – hoover dam power, 2014
- Jansen, Robert B. Advanced dam engineering for design, construction, and rehabilitation. (New York: Van Nostrand Reinhold. 1988), 664.
- Lüsted, M. A. The Hoover Dam. (Farmington Hills, MI: Lucent Books, 2003), 89.
- Lerner, K. and Brenda W. Environmental issues essential primary sources. Detroit, Mich: Thomson Gale, 2006), 54.
- Jacobson, Cecil Baltzar. Benefits to environment – Glen Canyon to Hoover Dams, 1972. 154
- Paul R. Encyclopedia of environment and society. (Thousand Oaks: Sage Publications, 2007), 582.