The Center for Land Use Interpretation Newsletter

CLUI Goes Down the Tube


663 The 12 foot diameter tunnel, looking east - upstream, in the future. CLUI photo

A CLUI VIDEO TEAM WAS dispatched recently to interview the workers at an obscured construction site in the Baldwin Hills, near the Center’s main office in Culver City, California. The site, it turned out, was an access shaft above a connection point in the City of Los Angeles’ new main sewer line, a massive and complex construction project that has been going on underneath the city for over ten years.

Though sometimes obscured by opaque sound absorbing material attached to 20 foot tall fencing (such as at the corner of La Brea and Jefferson Boulevards), vertical shafts like this one are visible at several sites around the city. They allow workers, materials, and equipment—including large tunnel boring machinesto descend the 50-100 feet into the ground to the level of the new sewer tunnel.

The tunnel is being built in three stages, and together each section will comprise a 30 mile long sewer pipe that runs from Glendale to the Hyperion Treatment plant, on the coast next to Los Angeles Airport (where the waste is treated in one of the nation’s largest treatment facilities, then is pumped out to sea and dissipated through a series of shower head like diffusers). Once complete, this new main sewer line for the city, averaging 10-12 feet in diameter, will replace the old system of smaller pipes, some of which are brick lined tunnels made in the 1920s. The old system is so overwhelmed that in some areas, during storms, the city has parked trucks on the manhole covers, to keep raw sewage from spilling onto the streets.

664 The access portal, behind a soundwall. CLUI photo

The first section of the new pipe to be built was a 12 mile long, 14 foot wide shaft called the North Outfall Replacement Sewer (NORS) pipe. Completed in 1993, this section of the pipe, between the Hyperion Plant and the Baldwin Hills, is already in use. The next phase, nearly complete, runs for 12 miles from the Baldwin Hills to the Los Angeles River, near downtown. This is a 12 foot diameter, steel lined pipe called the East Central Interceptor Sewer (ECIS). Over the past two years, ECIS was bored through the saturated soils, gassy oilfields, and superfund plumes along a course averaging 80 feet below the surface of the city. Phase three is a tunnel currently under construction, that runs alongside the Los Angeles River, from downtown to Glendale. Together the three phases of the project will have cost over a half a billion dollars.

The hole in the hills of Culver City is the connection point for the already built and partially in use NORS tunnel (the fist phase of the project), and the nearly completed ECIS tunnel (the second phase). At the bottom of the 70-foot deep rectangular shaft, with walls held in place by I-beams, sheet piling, and shotcrete, the two pipes are being joined with a valve installed between them. Like the other access portals, this one will be filled in once the pipe is complete, and the surface grade will be restored. Little will remain visible on the surface to indicate the buried highway of liquid waste flowing under the city.

At the Culver City portal, workers for the primary contractor on the ECIS project, a consortium called Kenny-Shea-Traylor-Frontier Joint Venture, met the CLUI video team, and led them into a metal cage that was picked up by a crane, and lowered into the pit. Once inside, the interview was conducted some distance down the gleaming ECIS pipe, to avoid the noise of jackhammers.

The video and photographs obtained on this and subsequent visits were presented at the CLUI’s exhibit hall in February as an exhibit called East Central Interceptor Sewer: A View Into The Pipe, sponsored by the Center for Land Use Interpretation Underground Program, in association with the Waste Programs division. The video was the first of a proposed series of video programs called “What Is This Place?” 

665 Descending into the pit in the cage. CLUI photo