History in the Making

Document Type



Southern California receives the vast majority of its yearly rainfall in the relatively short time period between the months of December and March. Occasionally, this intense rainfall creates floods that have historically threatened and devastated the communities of this region. The twentieth century proved challenging for local flood control agencies. California experienced tremendous population growth, resulting in migrants settling on the existing floodplains. Unaware of the periodic, hidden menace, newcomers were ruined when rivers and their tributaries flooded. It became clear that a significant change in flood control methods was required. In 1936, Congress passed the Flood Control Act appropriating funds for flood control. The Army Corps of Engineers took authority on flood control issues and began investigating the best possible solutions to assist communities like the Santa Ana River basin with the funds Congress authorized. The Army Corps devised a plan that they believed, at the time, was sufficient to protect Orange County. However, in March of 1938 a major flood struck southern California and demonstrated the need for a larger comprehensive flood control program. Ultimately, the affect of this program was the creation of immeasurable wealth for southern California. Property values increased, as did property taxes. Land deemed unusable because of floods could now be utilized. The creation of a modern comprehensive flood control program greatly aided the development of California’s economy—an economy which today ranks 8th in the world. This is the story of the implementation of modern flood control in the Santa Ana River basin and the devastating storm that demonstrated the need for such extraordinary measures.