Which dam was completed in 1938?

Shasta Dam is notable for its completion in 1938 and is a key project in California's water management system. It was constructed as a part of the Central Valley Project, designed to provide water storage, hydroelectric power, and flood control. Being one of the largest concrete dams in the United States, Shasta Dam plays a crucial role in managing water resources for agricultural, urban, and ecological needs in the region. Its significance also stems from contributing to the management of the Sacramento River and the broader health of California's water system.

Castaic Dam, Oroville Dam, and New Melones Dam were completed in later years (Castaic in 1973, Oroville in 1968, and New Melones in 1979). Each of these dams serves specific purposes related to water management but is not associated with the year 1938.