The dam forms Lake Cachuma, which provides the majority of water supplies within the county.

Although the Santa Ynez can reach massive flows in the winter, it usually dries up for several months of the year in the summer.

A large storage facility to catch winter floodwaters for use in the summer and autumn was desperately needed by the growing population of the region, especially that of south coast cities like Santa Barbara and Carpinteria.

However, that dam was plagued by siltation and was unable to fully serve the water requirements of the city.

[1] Construction on Bradbury Dam started in 1950 as part of a U.S. Bureau of Reclamation scheme called the Cachuma Project, intended to provide long-term water storage and delivery to Santa Barbara and other cities throughout the region as well as provide water for irrigation.