Construction update: Subsurface wall construction underway at new SoMa location; construction paused in Union Square, North Beach
The tunneling contractor has begun installing below-ground walls to prepare for tunneling at this site on 4th Street between Howard and Folsom streets.
Since our last update, construction in Union Square and North Beach has paused for the holiday season, while work at two sites in SoMa has continued to move forward. In addition, work to install subsurface monitoring equipment has commenced in Chinatown.
Here’s what you can expect in the next three weeks as construction continues in SoMa and Chinatown:
- Tunnel Launch Box (4th Street between Harrison and Bryant streets): The contractor will install beams across the below-ground walls that have been constructed around the perimeter of this site. Excavation and construction of an access ramp is also planned to begin. To facilitate construction, this block of 4th Street will remain closed to all vehicle traffic. The on-ramp to westbound I-80 at 4th and Harrison streets may be closed on weeknights from 8 p.m. to 4 a.m. and all day Saturday and Sunday. The sidewalk on the east side of the block will remain open to pedestrians. Traffic and pedestrian controls are in place. For more information on current construction impacts at this site, please check out this construction notice.
- Yerba Buena/Moscone Station Tunnel Pre-Construction (4th Street between Howard and Folsom streets): The tunneling contractor has commenced installation of below-ground walls, called headwalls, at the site of the future Yerba Buena/Moscone Station. The walls will cross 4th Street at two points on this block. At least two lanes of traffic on 4th Street will remain open at most times; however, the block may be reduced to one lane for one night to facilitate work involving large cranes. The contractor will continue working on the western side of the block, with at least two lanes open on the east side of the street (left lanes for southbound traffic). Pedestrian controls will be in place during periods of sidewalk impact.
- Chinatown Subsurface Instrument Installation (Stockton Street between Sacramento Street and Broadway): Crews will continue installing subsurface instruments that will measure ground conditions related to the Central Subway tunnel. One lane of traffic on up to two approximately half-block sections of Stockton Street may be closed at a time during construction hours. Construction hours are Monday to Friday, 10 p.m. to 7 a.m. More information is available in this construction notice.
We also post construction, auto detour and Muni impact information on our project Google Map.
We appreciate your continued patience while construction is in progress.