Ballona Creek Watershed

The Ballona Creek watershed covers approximately 130 square miles in the coastal plain of the Los Angeles basin. Its boundaries are the Santa Monica Mountains to the north, the Harbor Freeway (110) to the east, and the Baldwin Hills to the south. The watershed includes the cities of Beverly Hills, West Hollywood, portions of Los Angeles, Culver City, Inglewood and Santa Monica, unincorporated areas of Los Angeles County, and areas under Caltrans jurisdiction. The watershed is highly developed with 49% of it covered by roads, rooftops and other impervious surfaces.

Ballona Creek flows as an open channel for just under 10 miles from mid-Los Angeles through Culver City, reaching the Pacific Ocean at Marina del Rey harbor. The estuary portion  is soft bottomed, while the remainder of the creek is lined in concrete. Ballona Creek is fed by a network of underground storm drains, which reaches north into Beverly Hills and West Hollywood. Major tributaries include Centinela Creek, Sepulveda Channel, and Benedict Canyon Channel. The average dry weather flow at the watershed’s terminus is 25 cubic feet of water per second – a slow, steady flow. The average wet weather flow is 10 times higher and even more during large storms.

Water Quality in Ballona Creek
Ballona Creek and selected tributaries are impaired by pollutants (e.g. trash, metals, bacteria, nutrients) mainly because of the watershed’s large, dense population and the amount of impervious ground surfaces that prevent runoff from infiltrating into underground aquifers. Ballona Creek has several TMDLs that address trash, bacteria, metals, estuary toxic pollutants, wetlands sediment and exotic vegetation.

Ballona Creek’s Enhanced Watershed Management Program (or EWMP) identifies compliance measures including TMDLs and other water quality mandates, while maximizing potential benefits of storm water for local water supply. 

Related PDF documents:
BC Estuary Toxics TMDL Implementation Plan (7.7mb)
BC EWMP Work Plan (6.8mb)
Trash TMDL Implementation Strategy and Plan (4.3mb)
BC Bacteria TMDL Draft Implementation Plan (8.8mb)
BC Draft CIMP (9.2mb)
BC Metals TMDL Implementation Plan (7.1mb)

Ballona Creek Bacteria TMDL Project

Ballona Creek Bacteria TMDL Project