Los Angeles River

Los Angeles River, highlighted in red (on the left). The San Gabriel River is highlighted in red on the right
Los Angeles River in Los Angeles

The Los Angeles River starts in the San Fernando Valley, in the Simi Hills and Santa Susana Mountains, and flows through Los Angeles County, California, from Canoga Park in the western end of the San Fernando Valley, southeast to its mouth in Long Beach. Several tributaries join the once free flowing and frequently flooding river, forming alluvial flood plains along its banks. It now flows through a concrete channel on a fixed course.

Environmental groups and park advocates support the removal of concrete and the restoration of natural vegetation and wildlife. There are also plans for a series of parks along the river's city frontage in Los Angeles. The Los Angeles River also flows through several Los Angeles County communities and has been featured in many Hollywood films.

Before the opening of the Los Angeles Aqueduct, the river was the primary source of fresh water for the city. Although the Los Angeles region still gets some of its water from the river and other local sources, most comes from several aqueducts serving the area. The river suffers pollution from agricultural and urban runoff.


The Los Angeles River's official beginning is at the confluence of two channelized streams - Bell Creek and Arroyo Calabasas - in the Canoga Park section of the city of Los Angeles, just east of California State Route 27, at . Bell Creek flows east from the Simi Hills and Arroyo Calabasas flows north from the Santa Monica Mountains. From there the river flows east through a concrete flood control channel and very soon receives Browns Canyon Wash, which flows south from the Santa Susana Mountains, from the left. The river then bends slightly south and receives Aliso Canyon Wash, whose watershed adjoins that of Browns Canyon, from the left. The river then flows into the town of Winnetka, then Reseda and enters the Sepulveda Basin, a flood control reservoir formed by the Sepulveda Dam.[1][2][3][4]

As the river proceeds into the usually dry reservoir, it spills out into a channel that is similar to its historical, unchannelized form. It crosses under Balboa Boulevard and then passes through the outlet works of Sepulveda Dam, from the mouth. It flows again into a concrete channel and crosses under Interstate 405 as it passes through Van Nuys, Sherman Oaks, and Studio City, still flowing east. Paralleling U.S. Highway 101 briefly, it then veers southeast, away from the highway, and receives from the left the Tujunga Wash, one of its largest tributaries, which flows southwest and south from the Angeles National Forest in the San Gabriel Mountains. The river then rounds a bend to the northeast, now in a concrete box culvert, and crosses under California State Route 170 and Highway 101, and receives Burbank Western Channel on the left bank, from the mouth.[1][2][5][6]

The river then begins to parallel California State Route 134 as it winds past the city of Burbank and North Hollywood, then crosses under Interstate 5 and makes a sharp bend to the south-southeast as it curves around Griffith Park. It receives from the left Verdugo Canyon Wash, which drains much of La Cañada Flintridge and Glendale as it flows from the San Gabriel Mountains south through a water gap in the Verdugo Mountains, and crosses under State Route 134. Here, the river begins to flow over a natural riverbed, but enters another concrete section soon after. Paralleling Interstate 5 for the next few miles, the river runs by the eastern side of Griffith Park and the Harding-Wilson Golf Course. It passes Silver Lake Reservoir which is to the right, and crosses under California State Route 2, from the mouth.[1][2][7][8][9]

Making two meanders as it flows in a southeasterly direction, the river parallels the interstate and Riverside Drive then crosses under the interstate and California State Route 110 as it flows east of Elysian Park. It then receives the Arroyo Seco, another major tributary, from the left. The river flows south past the Mission Junction, a large railroad yard on the left. It enters a wider concrete channel with sloped sides, and crosses under Cesar Chavez Avenue, Highway 101, and Interstate 10 as it passes east of downtown Los Angeles, flowing past an interchange for Highway 101, California State Route 60, and Interstates 5 and 10 on the left. It then makes a gradual turn east and then turns southeast, flowing a few miles before it begins to parallel Interstate 710 near Maywood, Bell, Cudahy, and Commerce, from the mouth.[1][2][9][10]

Paralleling Interstate 710 south-southwest, the river then crosses under California State Route 42 and the interstate as it receives the Rio Hondo from the left, from the mouth. The Rio Hondo (deep river) now serves as a distributary for the San Gabriel River to the east via the Whittier Narrows Reservoir. The river then crosses under Interstate 105 and shifts slightly southwest, then flows east of Compton and west of Bellflower. After crossing under California State Route 91, it receives Compton Creek from the right, from the mouth. After crossing under Interstate 405 for the second time, from the mouth, it draws close to the Dominguez Channel to the west and flows due south to its outlet in Long Beach, under Interstate 710, past the RMS Queen Mary, and into the Port of Los Angeles.[1][2][9][11][12]


!-- This section is linked from Los Angeles, California -->

The river provided a source of water and food for the Gabrielino Indians for hundreds of years prior to the arrival of the Spanish. The Gabrielinos were hunters and gatherers who lived primarily off the fish, small mammals and acorns from the abundant oak trees along the river's path. There were at least 45 Gabrielino villages located near the Los Angeles River, concentrated in the San Fernando Valley, and Elysian Valley in what is present day Glendale. In 1769, Gaspar de Portolà during his 1769 expedition of Alta California named it El Río de Nuestra Señora La Reina de Los Ángeles de Porciúncula, so translated: The River of Our Lady Queen of the Angels of Porciuncula. It was referred to as the Porciuncula River.

The river was originally an alluvial river that ran freely across a flood plain that is now occupied by Los Angeles, Long Beach, and other townships in Southern California. Its path was unstable and unpredictable, and the mouth of the river moved frequently from one place to another between Long Beach and Ballona Creek. In the early nineteenth Century, the river turned southwest after leaving the Glendale Narrows, where it joined Ballona Creek and discharged into Santa Monica Bay in present Marina del Rey. During a catastrophic flash flood in 1825, its course was diverted again to its present one, flowing due south just east of present-day downtown Los Angeles and discharging into San Pedro Bay. (Prior to another major flood in 1862, it was joined by the San Gabriel River in present-day Long Beach, but in that year the San Gabriel carved out a new course to the east, and has discharged into Alamitos Bay ever since.)

Until the opening of the Los Angeles Aqueduct, the Los Angeles River was the primary water source for the Los Angeles Basin, and much of its channel was dry except during the winter rains. Unpredictable and devastating floods continued to plague it well into the 1930s (most notably the catastrophic 1938 flood that precipitated the recall of Los Angeles then-mayor Frank L. Shaw), leading to calls for flood control measures. The Army Corps of Engineers duly began an ambitious project of completely encasing the river's bed and banks in concrete, with only a trickle of water usually flowing down its middle. Ever since, it has primarily served as a flood control channel, fed by storm drains. The only portions of the river in which it is not completely paved over are in the flood control basin behind the Sepulveda Dam near Van Nuys; a 3-mile (5-km) stretch east of Griffith Park known as the Glendale Narrows; and along its last few miles in Long Beach.

Points of interest

Sepulveda Basin is a flood-control basin to control floodwater runoff. Except for infrequent but dramatic flood episodes, this dry-land flood control basin, most of which is leased from the Corps by the City of Los Angeles Department of Recreation and Parks, plays host to diverse uses today including athletic fields, agriculture, golf courses, a fishing lake, parklands, a sewage treatment facility, and a wildlife reserve.

The Los Angeles River bicycle path runs through the Glendale Narrows and is accessible to the public at its north end at Riverside Drive, at Los Feliz Boulevard, and at its south end at Glendale Boulevard. The bike path runs parallel to the 5 freeway for the majority of its length and has mile markers and call boxes for information and safety purposes.

The river's southern stretch forms the heart of an industrial corridor stretching nearly unbroken from Lincoln Heights to Long Beach. In this area, the busy Long Beach Freeway (I-710) and several high-voltage power lines run within a few hundred feet of the riverbed. Several rail yards are located along the river's banks in this stretch, as well. Just outside of the industrial corridor lie some of the most densely populated cities in the state of California, such as the cities of Bell, Cudahy and South Gate; most of these cities are in the river's flood plain and experienced significant flooding prior to channelization.