VISIONS OF SALT: SALINITY AND DRAINAGE IN THE SAN JOAQUIN VALLEY, CALIFORNIA, 1870-1970.

摘要

This dissertation is a history of the emergence and advancement of salinity and drainage problems in the San Joaquin Valley, California, and of how farm operators and governmental agencies have responded to such problems during the period 1870 to 1970. The origins of salt-related difficulties are discussed with emphasis given to the roles of local environmental conditions and irrigation practices. The responses are traced within the context of such factors as irrigation development and technological adaptation. The study is divided into three periods, each one coinciding first, with the expansion of salinity problems to a new level of severity, and second, with a dominant organizational or technological response. The first period, 1870 to 1915, is characterized by the individualist response; the second period, 1915 to 1945, by the collective or community-wide response; and the third period, 1945 to 1970, the valley-wide or regional response.;The third period, in which salinity problems emerged on the West Side of the Valley, is examined in chapters eight and nine. Chapter eight explores the expansion of irrigation and the movement which led to the federal requirement in 1960 that the construction of the San Luis Unit must include a regional drainage facility. The final chapter analyzes the struggle and ultimate failure of the state and federal governments to provide a comprehensive drainage facility on the West Side by 1970.;The first three chapters provide an introduction and historical background to the study of salinity problems in the San Joaquin Valley. Chapters four through six examine the first period. The Valley environment, early salinity problems, and the irrigators' responses are described in chapter four. Chapter five discusses the work of E. W. Hilgard and the California Agricultural Experiment Station. The attempts of two federal agencies to stimulate drainage activities in the Fresno area are chronicled in chapter six. Chapter seven focuses on the second period, when the organization of district-wide drainage systems and the use of ground water pumping brought water tables under control on the East Side of the Valley.