Monstrous tunnel-boring machine makes history at the lowest point in L.A.'s transit system

Below Walt Disney Concert Hall, down the block from the line forming outside the Broad Museum, sits the deepest point in Los Angeles’ subway system.

When it’s completed, the Bunker Hill station will be in a class of its own. At 110 feet below street level, it will be the only station without escalators, instead relying on a bank of elevators to lower passengers to the platform.

On Thursday, the site became a part of L.A. transit history.

In front of a gaggle of TV cameras and eager spectators, the crews made way for Angeli, the monstrous tunnel-boring machine that has been devouring bedrock beneath downtown Los Angeles since February, as it worked its magic.

At 110 feet below Grand Avenue at 2nd Street, downtown’s chorus of car horns and roaring vehicles is nothing more than a distant gray noise. Instead, the sounds of boots on metal platforms, power generators and a crane winch’s high-pitched squeal create the ambiance. Rows of sealed utility and power lines curve over the top of the cavern like an industrial art installation.

When Angeli approached its final destination for the day on Thursday — the end of a 22-foot-wide tube previously sealed by concrete — a deep thunder akin to cracking ice sheets boomed through the job site.

“It sounds like King Kong behind the gates,” one worker joked.

And minutes later, when the machine’s wide face of scrapers, discs and cutters gnawed through the wall, officials celebrated the event as a milestone in the construction of Metro’s Regional Connector Transit Project.

Chunks of rock, mud and dirt spilled onto the ground while the machine’s mud-caked face continued to twist while swallowing dirt and spitting water to loosen the soil.

“I’m a big proponent of public transportation, most of our guys are. We’re proud to be a part of this,” said project engineer Christophe Bragard.

The 1,000-ton, 400-foot-long machine began its subterranean journey four months ago in Little Tokyo. After breaking through a wall of earth at the planned Grand Avenue Arts/Bunker Hill Station on Thursday morning, the machine will veer left and continue digging through downtown’s Financial District until it reaches 4th and Flower streets in a couple of weeks.

When the entire $1.75-billion project is completed in 2021, the S-shaped tunnel will allow commuters to use a single train to move from Long Beach to Azusa and from East L.A. to Santa Monica, linking some of the county’s most far-flung residents without time-consuming transfers.

“The dream of connecting the Metro Rail system to the entire region is now becoming a reality,” Metro board chair John Fasana said in a statement.

Angeli journeyed 1,440 feet from Little Tokyo to Bunker Hill, said Metro spokesman Rick Jager.

Crews have already set 18,000 tons of precast concrete in the machine’s wake and sealed the tube with 1,000 gallons of grout.

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