News | National Academies | July 2024

Reviving the Los Angeles River: Engineering Alongside Nature and Society

Much of the Los Angeles River is currently a concrete channel. Angelenos often joke that it is hardly a river, given that it is frequently dry and perhaps better known as the location for motorcycle and car chases in Hollywood blockbusters. Yet, the concrete channel serves an important purpose. The channel and multiple dams were put in place as flood control measures by the U.S. Army Corps of Engineers after a series of devastating storms in the early 1900s (Gumprecht 2001). The concrete channel fixed in place a river that was previously a dynamic landscape that frequently flooded and changed course. The denuded and straightened channel also reduced flow resistance, easing the passage of high flows towards San Pedro Bay.