Large river rocks are placed into wet concrete to deter errant motorists from entering the tunnel portal.
This notice provides a general project update and look-ahead which includes information about work activities, traffic, and transportation impacts taking place over the next few weeks along the project alignment.
For more project information, visit the Central Subway project page.
Construction Progress:
A piece of kinetic public art entitled Microcosmic by artist Moto Ohtake has been installed atop the mast at the 4th and Brannan surface station.
Surface Work and 4th/Brannan Station
Before entering into the surface-to-tunnel portal just north of 4th and Bryant, a section of the new T Third Line extension will travel on the surface of 4th between King and Bryant. To increase access, there will be one surface-level station platform added just north of the 4th and Brannan intersection. Tactile paving tiles, public art, and and an access ramp are currently being installed and built there. Final intersection work at Brannan is planned for the weekend to connect tracks along 4th Street.
Last month, the centerpiece of public art at the 4th and Brannan surface station platform was installed. The piece is a kinetic sculpture entitled Microcosmic, by Bay Area artist Moto Ohtake. This installation is one of 10 major art pieces that are a part of the Central Subway Project.
Just to the south of the surface platform, the reinforced concrete rail bed and dual trackway were also installed across the 4th and Brannan intersection, closing one of the last gaps in rail installation for the project.
Pallets of terrazzo wait to be mixed while workers install conduits and structural steel at the future fare gate area for Yerba Buena/Moscone Station.
Yerba Buena/Moscone Station
The first subway station north of the tunnel portal will be Yerba Buena/Mosone Station, with the entrance plaza located at 4th and Clementina (near Folsom Street). Street-level elements such as elevator shafts and steel framing are being constructed. Crews are also building out the station interior, installing permanent lighting, terrazzo floors, concourse-to-platform elevators, wall panels, conduits, and utilities.
Crews install lighting, ceiling panels, and a public art array comprised of LED panels inside the south concourse of Union Square/Market Street Station.
Union Square/Market Street Station
The largest of the three new subway stations will be Union Square/Market Street. This station will link directly to Powell Station via an underground concourse connection, and will feature two station entrances: One at the southeast corner of Union Square, and a refurbished entrance at Stockton and Ellis. Crews have continued to build out the station interior, constructing partition walls on intermediary floors, adding utilities, and installing finishing elements such as wall and ceiling panels, public art, and laying out the terrazzo floor both on the concourse and station platform.
Recently, the boarding island and bulb-out for buses was also reopened just north of Geary for the 30/45/8 buses traveling outbound, replacing the temporary stop south of the intersection.
Sound reduction panels are being attached to steel brackets mounted to the arched concrete ceiling of the Chinatown-Rose Pak Station platform cavern.
Chinatown-Rose Pak Station
The deepest and most impressively complex of the three subway stations to excavate and construct is Chinatown-Rose Pak Station. The future station entrance will be located at the southwest corner of Stockton and Washington, and will be topped by a rooftop plaza. Interior walls, multiple stairways, shotcrete and waterproofing for exterior walls, and station utilities are all currently being added. Work on the rooftop plaza that will be open to the public is underway.
Looking ahead: From January 13 to February 1 the Lunar New Year "construction moratorium" will be in effect to make way for all the festivities in Chinatown. Active work will cease along Stockton Street, but will continue inside the station footprint.
Potential Vehicular/Pedestrian Impacts
The west sidewalk and one southbound lane of Stockton adjacent to the work site south of Washington may experience brief closures from time to time due to concrete pours. Detours will be indicated when in effect. A temporary stop has been added for southbound Muni routes 8, 30, 45 and 91 on Stockton at Washington. This stop will eventually be located in directly in front of the station to make transfers easy.