Maps of Water in California

State Water Project Map

California State Water Project (click to enlarge)

In 1933, the California Legislature passed the Central Valley Act to allow for construction of a system that would bring water from the Sacramento River down to Southern California. Because of the Great Depression, construction was not able to begin until 1935.

California experienced a huge population boom after World War II, and it quickly became clear that the current local water supplies would not meet future needs.