Crews Burrow 1st Feet of 2-Mile Valley Subway

The thunder of a 200-foot-long tunneling machine Monday announced the birth of the subway age in the San Fernando Valley, as workers began boring the underground path for the Metro Red Line cars that will link the Valley with Downtown Los Angeles.

Shortly before 10:30 a.m., the mammoth excavator rumbled to life beneath Lankershim Boulevard in North Hollywood, punching forward through a foot of earth to inaugurate a project that will stretch south for two miles to Universal City.

By the year 2000, twin tunnels from North Hollywood are to connect with tubes beneath Hollywood Boulevard to create a seamless ride from Union Station through the city’s historic movie district and underneath the Santa Monica Mountains to the eastern Valley.

“This represents another important step in the continuing progress of the Red Line,” said Franklin E. White, chief executive officer of the Metropolitan Transportation Authority. “Each time we begin a new link, we’re closer to providing a complete and modern transit system that the people of the region will be able to use for decades to come.”

Mindful of the construction debacle that led to a temporary halt in federal funding for the rail line, MTA officials stressed they will be guarding against a repeat of the problems that caused Hollywood Boulevard to sink nearly a foot last July. Although both funding and tunneling in the area eventually resumed, that project is again at a standstill after the ground dropped another two inches last week.

Contractors are applying lessons from last summer to the North Hollywood segment, which will run through soils similar to those beneath Hollywood Boulevard, said project manager Charles Stark. Work crews are required to use steel struts instead of wood inside the new tunnels and survey for leaking water mains.

“We’ll be doing constant monitoring of settlement,” Stark said.

The contractor, Obayashi Corp. of San Francisco, will also be alert for volatile gases such as hydrogen sulfide and methane. But “neither we nor the contractor nor Cal/OSHA expects to find any,” Stark said.

Construction commenced Monday on the easterly tunnel, with work on the west side scheduled to start in a month. As workers scurried beneath steel beams and catwalks latticed over a noisy excavation shaft 70 feet deep, the tunneling machine scooped out a chunk of earth and inched forward under the intersection of Lankershim and Weddington Street.

Officials estimate that construction will progress between 50 and 200 feet daily, performed by work crews round-the-clock five to six days a week. The machines will bore through soil that once lined the bottoms of ancient oceans.

The quality of the earth is similar to that beneath Hollywood Boulevard, Stark said. A report by a private engineering firm last fall to the Federal Transit Administration warned that “these soils are referred to as ‘collapse-prone’ and create the most problems when wetted.”

To deal with any excessive subsidence, the MTA has formulated a contingency plan that closely follows the report’s recommendations. In addition to the steel wedges, the agency has a stockpile of other steel reinforcements close by. Workers also have ready access to grouting material, said MTA spokesman Bill Heard.

“These are lessons learned the hard way,” Heard said.

Excavation under Lankershim southeast to Universal City should last about six months, officials said. Pouring in the concrete will take another 12 to 18 months. The expected completion date for the $65.4-million project is February, 1997.

Tunneling south from Universal City to Hollywood is scheduled to begin late this year or early next year to prepare for an opening of the Hollywood-to-Valley Red Line extension in July, 2000.

MTA officials said they do not expect the tunneling to cause any disruptions to local businesses or traffic. “The only way they’ll know we’re (tunneling) is when they see the truckloads of dirt coming out of there,” agency spokesman Steve Chesser said.

When the core of the Red Line system--the 17.4-mile route from Union Station to North Hollywood--is finished in five years, the MTA projects daily ridership to average about 325,000 passengers, including 38,300 boardings between the North Hollywood and Hollywood/Highland stations.

The terminus at North Hollywood is a key element of an ambitious plan to reinvigorate the “downtown” portion of that community, a major shopping and entertainment district after World War II that has since fallen into some disrepair.

With a subway station, residents will have easier access to the restaurants and night life spots planned for the area. The neighborhood plays host to several live theaters, with plans calling for construction of an additional facility capable of holding 12 live theaters under one roof.

Last week, the Los Angeles Planning Commission took the first steps to allow artists in the area to convert commercial buildings into lofts and studios.

Kevin McCarney, president of the Universal City-North Hollywood Chamber of Commerce, said redevelopment efforts are aimed at creating a Bohemian enclave that would attract residents from throughout the city, including patrons of the CityWalk attraction a quick subway ride away.

“It’s going to allow people who go to CityWalk to very quickly make their way to the live theater district in North Hollywood, which is just one stop away,” McCarney said. “It stretches the positive economic impact into an area that really needs revitalization.”

Times staff writer Richard Simon contributed to this story.

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Tunneling Begins

The digging that got under way in North Hollywood on Monday represents the start of work on Segment 3 of the Metro Red Line project, which will connect Downtown Los Angeles with the San Fernando Valley.

The line is projected to carry 38,300 passengers a day between the North Hollywood and Hollywood/Highland stations once the segment opens in the year 2000.

Red Line Facts

10,541 feet: the length of two tunnels that will run from the North Hollywood station to the Universal City station.

60 feet: depth below street level.

17 feet: diameter of completed tunnel.

$65.4 million: amount of contract for the two tunnels.

250: number of workers on site, 24 hours a day, five to six days a week.

Source: Metropolitan Transportation Authority

Researched by HENRY CHU / Los Angeles Times