Thesis (Ph.D.)--Massachusetts Institute of Technology, Program in Science, Technology and Society, February 2000.Includes bibliographical references (p. [327]-349).This dissertation examines how Americans have transformed the environment through the construction of new technologies and the roles of technical professionals in bringing about these changes. In the twentieth century, federal engineers, working with local Western boosters and their federal superiors, transformed the West's waterscape. Between 1900 and 1970, engineers of the U.S. Bureau of Reclamation--only one of three federal agencies that built dams-constructed over 400. On the Columbia River alone, federal engineers constructed thirteen large dams that turned the nation's fou...