Tunnel boring machine Big Alma, shown here on the right, began tunneling under 4th Street. On the left is the entrance to the parallel tunnel being built by TBM Mom Chung. There are now two 350-foot-long, 750-ton tunnel boring machines mining under 4th Street to construct the Central Subway’s pair of parallel tunnels. Our second […]
Due to the Thanksgiving holiday, this update covers the next two weeks. Our next update will be on Friday, Dec. 6. Happy Thanksgiving from the Central Subway team! Near Union Square, Stockton Street part of Stockton Street is now reopened. In this shot, crews finish the paving and traffic striping. During the next 17 days, […]
In the operating cabin of TBM Mom Chung, two TBM operators monitor tunneling conditions provided from a variety of state-of-the-art instruments. Next week our first tunnel boring machine, Mom Chung, will pass beneath Market Street and the existing BART and Muni Metro tunnels, crossing from SoMa and into Union Square. The tunnel, one of two […]
In the new tunnel, two crewmen watch as a cart approaches, carrying with it tunnel segments for TBM Mom Chung to install. During the next 10 days, tunneling and tunneling preparatory work will continue in SoMa, Union Square and North Beach. Work to prepare for station construction is continuing in Chinatown and northern SoMa. In […]
We have completed the current phase of work on Stockton Street and are restoring the construction zone. Stockton will reopen to traffic in time for the holidays. During the next 10 days, tunneling and tunneling preparatory work will continue in SoMa, Union Square and North Beach. Work to prepare for station construction is continuing in […]
Beneath 4th Street, segments of the new subway tunnels are delivered underground. Our first tunnel boring machine, Mom Chung, has now built about 1,400 feet of tunnel. During the next 10 days, tunneling and tunneling preparatory work will continue in SoMa, Union Square and North Beach. Work to prepare for station construction is continuing in […]
