California’s Sacramento-San Joaquin Delta: Formation and Obscuration of a Regional Identity

California’s Sacramento-San Joaquin Delta is one of the world’s great inland deltas and has been occupied continuously since it was formed by rising sea levels at the end of the last Ice Age. As Native American populations were displaced during the Gold Rush, the Delta developed along a historical trajectory dramatically different from the San Francisco Bay area, immediately to the west, and even from the Central Valley, which merges into the Delta from the remaining three directions. The 700,000 acres of low-lying islands and sloughs that compose the Delta have been dramatically altered by decades of reclamation, as vast wetlands were converted to agricultural fields. Immigrants, beginning with Chinese and Japanese settlers, carried out this work and gave the Delta a diverse ethnic composition that set it apart from its surroundings. The Delta has also been the site of a rich fish culture and numerous salmon canneries, before the salmon runs were extirpated by massive hydraulic projects.

            During the mid-twentieth century, California constructed the Central Valley Project and State Water Project to transport much of the state’s developed water supply from northern California, through the channels of the Delta, to more arid and more populated southern California. Even as it serves as the linchpin of the state’s hydraulic regime, providing drinking and irrigation water for twenty million people, the Delta remains rural and far less developed than its surroundings; hunting, fishing, and recreation remain the dominant activities. Ironically, despite its uniqueness, many Californians who reside outside of the Delta view the region in simple mechanistic terms—primarily as a water conveyance system. This paper integrates social and environmental history as it examines the reasons why the Delta has followed its distinctive historical trajectory, and investigates why its identity is often submersed by the state’s perpetual quest for water.