Hoover Dam: Difference between revisions

[[File:Boulder damsite sketch.jpg|thumb|Sketch of proposed damsite & reservoir, circa 1921]]

The contract to make the Boulder Dam was awarded to [[Six Companies|Six Companies, Inc.]] on March 11, 1931,<ref>Construction of Hoover Dam: a historic account prepared in cooperation with the Department of the Interior. KC Publications. 1976. ISBN 0-916122-51-4.</ref> a joint venture of [[Morrison-Knudsen]] Company of [[Boise, Idaho]]; [[Utah Construction Company]] of [[Ogden, Utah]]; Pacific Bridge Company of [[Portland, Oregon]]; [[Henry J. Kaiser]] & W. A. [[Bechtel Corporation|Bechtel Company]] of [[Oakland, California]]; MacDonald & Kahn Ltd. of [[Los Angeles, California|Los Angeles]]; and the J.F. Shea Company of Portland, Oregon. The chief executive of [[Six Companies]], [[Frank Crowe]], had previously invented many of the techniques used to build the dam.

During the concrete-pouring and curing portion of construction, it was necessary to circulate refrigerated water through tubes in the concrete. This was to remove the heat generated by the chemical reactions that solidify the concrete, since the setting and curing of the concrete was calculated to take about 125 years if cooling was not done. Six Companies, Inc., did much of this work, but it discovered that such a large refrigeration project was beyond its expertise. Hence, the [[Union Carbide Corporation]] was contracted to assist with the refrigeration needs.