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<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
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