In a parking lot at Stockton and Green, crews have built this underground shaft. From it, we will improve and stabilize ground conditions beneath Columbus Avenue during tunneling. Due to the upcoming holidays, this update covers the next two weeks of Central Subway work. There will be no update next Friday, Dec. 27. Happy holidays […]
Underground on 4th Street, two tunnels are now in construction. Here we see the entrances to both, beneath 4th and Harrison. During the next 10 days, Central Subway work will continue at sites in SoMa, Union Square, Chinatown and North Beach. This post contains brief updates about what is happening in each neighborhood. For more […]
Inside TBM Mom Chung, the new tunnel curves as it passes below Market Street. Our tunneling crews successfully and safely completed the crossing under BART last week. We completed an important construction milestone last week as our tunneling contractor and TBM Mom Chung successfully and safely tunneled under Market Street and the existing BART and […]
Using time-lapse cameras installed underground, we’ve condensed the first months of tunneling into this captivating two-minute video. In the video, Central Subway crews assemble tunnel boring machine (TBM) Mom Chung and drive the state-of-the-art tunnel builder north under 4th Street to build San Francisco’s first new subway line in decades. The video shows the TBM […]
