80 Feet Below: Scenes From The Central Subway's Subterranean Construction

Deep underneath the streets of San Francisco, workers have been busy constructing the Central Subway.

The $1.578 billion project will extend Muni's T-Third metro line, providing a 1.7-mile direct transit link between the Bayshore/Mission Bay neighborhoods and SoMa, downtown, and Chinatown.

In addition to a street-level station at 4th and Brannan, three subterranean subway stations are currently under construction: the future Yerba Buena/Moscone, Union Square/Market Street, and Chinatown stations.

The Central Subway is expected to open to the public in 2019. But even though that's two years away, here are someĀ photos that capture the project's underground progress:

A large steel bucket is raised to the surface at the Chinatown station.
Material removed during excavation work underneath Chinatown is dumped at the surface, to be loaded on a waiting truck.
The drill rig (stationed at the cross-cut cavern entrance under Chinatown) has multiple arms.
A look at the northbound tunnel before it is concreted and laid with tracks.
Workers drilling drill pilot holes into the exterior walls.
A worker smoothes a temporary steel beam at the Yerba Buena/Moscone Station.
Work being done at the future Chinatown Station.
At the Chinatown Station, workers inspect the placement of steel mesh.
A mechanic works on a jackhammer fitted to a large excavator below Union Square.
A bobcat is driven by workers to help grade the bottom of the station box at the future Union Square Station.
An excavator fitted with a grinding wheel works to excavate sections of the Chinatown Station.
Construction equipment deep below Fourth Street.
Workers make progress at the Union Square/Market Street Station construction site.

Never miss a story.

Subscribe today to get Hoodline delivered straight to your inbox.