L.A. River

From it’s humble beginnings as a seasonal creek near the Ventura County line, to it’s proud flow into Queensway Bay in Long Beach, the Los Angeles river travels 52 miles through 25 communities representing nearly every ethnic and economic demographic in the city. It’s reputation as a natural waterway versus giant sewer system is hotly debated among naturalists, who decry the loss of habitat and human access and want to restore it to a more organic state, and engineers, whose main concern is protecting local residents by discharging runoff into the ocean as quickly and efficiently as possible.

As the natural watershed for the Los Angeles basin, the river collects runoff from an 870 square-mile area, including the Santa Susanna Mountains, the San Gabriel Mountains, and the Santa Monica Mountains. The path of the LA River determined where the city’s founders established the town in 1769, and it was the original source of drinking water until population growth made its supply insufficient and William Mulholland was forced to construction the LA Aqueduct in 1913. After a catastrophic flood in 1938 destroyed property and lives, the Army Corps of Engineers was brought in to design an efficient and self-contained run-off system of storm drains, catch basins and dams.

Urban growth and rapid industrialization eventually placed the possible high-water mark of a serious flood well above the crest of the channel’s containment, so in the late 1990s, the corps chose to perform modifications to increase it’s capacity. Faced with the dilemma of having existing bridges and railroad trestles crossing too close to the elevated water surface, the engineers were challenged to design a system of pier-nose extensions to reduce velocity and flow, thereby “tricking” rushing flood waters into ducking under the existing structures.

The river is home to a diverse wildlife habitat. Over 300 species of birds and 60 species of native plants have been recorded in the river area. In 2000, the State Legislature approved $45 Million to acquire land along the banks of the river to create a recreational state park with multi-use sports fields, tennis courts and running trails. There are numerous non-profit organizations and government agencies working together on watershed management projects that seek to balance management of natural resources with the environmental and social impact of flood control.