Temescal Canyon Low Flow Diversion

A Low Flow Diversion (LFD) structure is scheduled to be constructed at Temescal Canyon and Pacific Coast Highway (Los Angeles) beginning in late September 2002.

The Low Flow Diversion is a pollution control device that will greatly reduce the amount of contaminated urban runoff that flows to Santa Monica Bay.

Questions of interest:

Where exactly will this Low Flow Diversion be located?

How will it impact traffic?

How does an LFD work?

Additional information.


Where exactly will this Low Flow Diversion be located?

The Low Flow Diversion will be constructed at the intersection of Temescal Canyon Road and Pacific Coast Highway.


How will it impact traffic?

Beginning later in the month of September 2002, construction will alter routes between Temescal Canyon Road and Pacific Coast Highway.

To download a complete traffic map showing the diversions and construction area, click on the PDF file below:


How does a Low Flow Diversion work?

A Low Flow Diversion is a structural device that routes urban runoff from canyons, streets and small watersheds away from the storm drain system or waterway, and redirects it into the sanitary sewer system, where the contaminated runoff then receives treatment and filtration before being discharged into the ocean. As the name suggests, the unit collects street runoff and, through a series of tanks and pumps, diverts the liquid flow into the sanitary sewer system, and is rerouted to the City’s Hyperion Sewage Treatment Plant (HTP).

Additional information.

Low-flow diversions eliminate contaminated runoff from reaching beaches and shoreline waters by diverting the flow to a sanitary sewer. This strategy will protect people from runoff-borne microorganisms that cause illness, and also protect marine organisms from harmful pollutants such as metals and pesticides. Studies in Santa Monica Bay have demonstrated that swimmers have an increased risk of illness when swimming in water contaminated by storm drain runoff. Likewise, runoff-contaminated water has been shown to be toxic to marine organisms.
Temescal Canyon Low Flow Diversion Site (click on image to download flyer)

By stopping runoff contamination from reaching the surf zone, low-flow diversions, protect beachgoers and eliminate the need to estimate when and where levels of pollutants are harmful. In fact, many other agencies in southern California have incorporated low-flow diversions into their overall strategy to control runoff pollution. Examples of these agencies include the Counties of Los Angeles and Orange, and the Cities of Huntington Beach, Laguna Beach, and San Diego.