CREST - Cleaner Rivers through Effective Stakeholders TMDLs

CREST Activities - L.A. River

L.A. River Description - The Los Angeles River flows 51 miles from the western end of the San Fernando Valley to the Queensway Bay and Pacific Ocean at Long Beach. The headwaters are at the confluence of Arroyo Calabasas and Bell Creek. From the confluence of Arroyo Calabasas and Bell Creek, the Los Angeles River flows east through the southern portion of the San Fernando Valley, bends around the Hollywood Hills before it turns south onto the broad coastal plain of the Los Angeles Basin, eventually discharging into Queensway Bay and thence into San Pedro Bay West of Long Beach Harbor. Together with its several major tributaries, notably the Tujunga Wash, Burbank Western Channel, Arroyo Seco, Rio Hondo, and Compton Creek, the Los Angeles River drains an area of about 834 square miles. Of this area, the incorporated cities and unincorporated portion of Los Angeles County comprise 584 square miles. The remaining acreage consists of the Los Angeles National Forest and other uses.

Most of the Los Angeles River channel was lined with concrete between 1935 and 1959 for flood control purposes. This reach is lined in concrete except for a section of the river with a soft bottom at the Sepulveda Flood Control Basin. The river is again lined in concrete for most of its course except for a seven-mile soft bottomed segment between the confluence of the Burbank/Western Channel near Riverside Drive and north of the Arroyo Seco confluence. Three miles of this segment border Griffith Park (encompassing 4,217 acres). Four miles downstream, the river flows parallel to Elysian Park (585 acres in size). From Willow Street all the way through the estuary, the river is soft bottomed with areas of riparian vegetation. This unlined section is about three miles long. (Source: Trash Total Maximum Daily Loads for the LA River Watershed, California Regional Water Quality Control Board, Los Angeles Region, September 19, 2001.)

The Los Angeles River is segmented into 6 Reaches in the 303(d) listing of impaired water bodies, as follows:

Water quality impairments for the LA River and its tributaries are shown on the attached map of the 2002 303(d) listingsPDF.

A Consent Decree issued on March 23, 1999 and signed by Heal the Bay, Santa Monica BayKeeper, and the USEPA mandates a schedule for the development of TMDLs for the LA River for the following constituents:

TMDLs for trash, nutrients and metals have already been developed. CREST is currently focused on preparing a TMDL for bacteria.