Subway station taking shape below streets of San Francisco's Chinatown

SAN FRANCISCO (KGO) -- A small handful of reporters joined San Francisco Mayor Mark Farrell as he toured the underground cave that's soon to become the Chinatown Central Subway station.

Boarding an elevator cage dangling from a crane, the group descended more than 100 feet below street level, through a column resembling a mineshaft -- because that's essentially what it is. Unlike the other two underground stations in this second phase of Muni's Third Street light rail line, contractors say the Chinatown station will be the first in the U.S. to be built entirely underground -- instead of being dug as an open trench, then covered up.

The main open space -- called the "platform cavern" -- is 54 feet wide, and 42 feet high. Mayor Mark Farrell saw it for the first time, with reporters in tow.

RELATED: San Francisco Central Subway project reaches milestone as concrete poured

"This is awe inspiring to be down here," Farrell said.

Farrell has long been a champion of the Central Subway -- a project that's seen its share of both controversy and delays.

"The more that we can put traffic underground, the better we're gonna be -- it's going to be a quicker, safe transportation system for everybody.

Putting traffic underground is a big job -- one that's just hit a major construction milestone.

"We've completed what we would consider the biggest obstacle -- the mining operation," said acting program manager Albert Hoe. "So, that's why you see all the finished work here. No more dirt here, except for the concrete."

The spot where officials spoke to reporters is actually seven feet below where the surface of the platform will ultimately rest. The emptiness of the station underscored its enormity.

RELATED: San Francisco Central Subway line opening delayed

"I was down in this station a year ago when it was pretty much just a dirt pit," said MTA board chair Cheryl Brinkman.

She said the subway is on track to take paying customers by December 2019 -- a year later than originally planned, and still badly needed.

"I think everybody recognizes that the surface level buses are so overcrowded, it's a horrible experience for people trying to get on and off those buses," Brinkman said.

With the concrete finished, workers will install giant sheets of yellow waterproofing material before they move on to flooring, tracks, fixtures and utility lines. But Farrell said he already has his eye on stations in North Beach and Fishermen's Wharf.

"This is the future of our city," Farrell said. "And if we want to really be thinking about the future of San Francisco, we need to have this throughout the city of San Francisco."

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