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<br />c <br /> <br />(: ..' <br /> <br />00 <br /> <br />- <br /> <br />~. <br />, <br /> <br />The Dam <br /> <br />The Fundamental Problem <br /> <br />A fter the Boulder Canyon Project was <br />authorized. the problem of constl11ction <br />was placed squarely before Reclamation <br />engineers. To achieve the purposes set <br />forth in the legislation, the low-lying <br />valleys of Arizona and southern California <br />had to be protectcd from the yearly <br />threat of Hood and the annual spring <br />runoff needed to be stored for later use. <br />The reservoir created by any dam would <br />have to be large enough to store the vast <br />quantities of sediment annually carried <br />downstream by the river. And a IXlwer- <br />plant large enough to economicaJly use <br />the full flow of the river, serve <br />power markets in the Southwest, and <br />assure repayment of the project had to <br />be provided. <br />To effectively harness the river and <br />obtain the desired objectives, a huge dam <br />more than 700 feet high would have to <br />be constructed. The reservoir created by <br />a structure this massive would safely <br />store the normal flow of the river for 2 <br />years. Measured by volume, the rcser- <br />voir would be the largest artificial lake <br />in the world. When tilled to maximum, <br />it would impound more than 31 million <br />acre-feet of water, or cnough to cover the <br />State or Pennsylvania one foot deep. <br />And it would be large enough to trap the <br />millions of tOilS of sediment which the <br />Colorado carried downstream every year <br />without impairing its storage capacity or <br />interfering with its power generating <br />capability. In fact, a reservoir this large <br />would make it possible to construct a <br />powerplant capable of producing over 6 <br />billion kilowatt-hours of energy annually. <br />As is often the case in undertakings <br />without precedent, there was opposition. <br />Some critics viewed the dam as a poten- <br />tial white elephant. Financially speaking, <br />they believed it would take many years <br />for the power market to absorb the <br />energy produced. Othcr critics said that <br />the fluctuating reservoir, loading and <br />unloading the carth's crust, would set up <br />destructive emthquakes. There were those <br />who magnified the difticulty of controlling <br /> <br />Aerial \"ie\l' looking I/fJ.I',reall/ 10 lJoo\'('r Dam lI'ilh <br />Lake Mead in hackgrolflld <br /> <br />the river dming construction until it <br />seemed insullllountable, or predicted that <br />the reservoir would fill with sediment, <br />limiting its llsefullife. Some said there <br />were so many unknown and unpredictable <br />factors involved in such an undertaking <br />that the project should be abandoned. And <br />in the minds of some was the thought of <br />what would happen if the dam failed after <br />it was built - the whole area below Black <br />Canyon would face utter destruction. <br />There were serious problems to be <br />solved. What contractor, for instance, <br />would dare undertake such a mammoth <br />job? The proposed damsite was in a <br />desolate region - where there were no <br />transportation facilities or living quar- <br />ters; where protection from the harsh and <br />unfriendly natural elements did not exist. <br />All these questions and problems were <br />raised but Reclamation went steadily for- <br />ward with exploration and preliminary <br />work. Geologic examinations revealed <br />that faults which passed through the <br />block of rock on which the dam was to <br />rest had long since healed - the block was <br />sound. Challenges were there, but none <br />that could not be met. The job could, <br />and did, go on. <br />Engineering specitications and draw- <br />ings for the dam and appurtenant struc- <br />tures were being rapidly prepared in the <br />Bureau's main design office in Denver, <br />Colorado. Design and specification work <br />was being pushed forward so construc- <br />tion could start as soon as possible. The <br />year was 1930, and the country was in a <br />depression. <br />The specifIcations were completed 6 <br />months ahead of schedule. On March <br />II, 1931, the Secretary of the Interior <br />awarded the contract for construction <br />of Hoover Dam to the lowest bidder, <br />Six Companies, Inc., of San Francisco, <br />California. Six Companies, known <br />on the job as the "Big Six," was com- <br />posed of the Utah Construction Co.; the <br />Pacific Bridge Co.; Henry J. Kaiser and <br />W. A. Bechtel Co.; MacDonald & Kahn <br />Co., Ltd.; Morrison-Knudsen Co.; and <br />J.F. Shea Co. All members of the group <br />were major western contracting films. <br /> <br />The bid was $48,890,995.50, the <br />largest construction contract let by the <br />Federal Government up to that time. <br /> <br />Preliminary Construction Steps <br /> <br />Before construction of Hoover Dam <br />could begin. all essentials for living and <br />working in the desert had to be planned <br />and built. tncomplete planning would <br />mean costly delays in construction. It <br />was the responsibility of Reclamation <br />engineers and the contractors to plan this <br />project so well that nothing would be <br />overlooked. <br />The problem of living qumters re- <br />quired particular attention. Construction <br />workers, recruited from all parts of the <br />Nation, had to have places to live. They <br />could not be expected to live in the im- <br />mediate vicinity of the damsite, where <br />summer temperatures as high as 1250 F <br />caused heat waves to rise from the can- <br />yon as from a blast furnace. <br />After studying climate and soil condi- <br />tions in the area, Reclamation engineers <br />selected a location 7 miles southwest uf <br />the darnsite. There, on a high plateau, a <br />complete town - Boulder City, Nevada- <br />was erected. Homes were built, lawns <br />and parks planted, streets laid out and <br />paved, and schools, churches, and stores <br />erected. A sewer system was installed, <br />and Colorado River water was piped into <br />the town. A modern oasis was created in <br />a desert wilderness. <br />Construction materials would be re- <br />quired in quantities never before shipped <br />to a single construction job in so short a <br />time - 5 million barrels of cement, 18 <br />million pounds of stmctural steel, 21 <br />million pounds of gates and valves, and <br />840 miles of pipe were actually hauled by <br />rail to the damsite during the first 4 <br />years of construction. <br />A never-be fore-attempted project like <br />construction of Hoover Dam demanded <br />specialized machinery. For example, <br />tmcks as small as 16-cubic yards capaci- <br />ty and as large as 50-ton capacity were <br /> <br />t9 <br />