Construction Update
August 24-September 2, 2013
During the next 10 days, construction to prepare for tunneling will continue in SoMa and Union Square. In North Beach, demolition of the Pagoda Palace will continue. No Central Subway construction is planned in Chinatown.
For descriptions of construction impacts in each neighborhood, scroll down or click on the links below. We also post construction, traffic detour and Muni impact information on our project Google Map.
Construction impacts are planned to change at these locations by September 2:
- Southern SoMa (Harrison to King/Berry): 4th Street between Harrison and Bryant may fully close some evenings and weekends starting Tuesday, August 27, to allow for installation of tunnel boring machine segments. Two lanes of traffic will remain open at all other times. Contact us at central.subway@sfmta.com if you have questions about the closure schedule. On Bryant Street at 5th Street, the left lane and several parking spaces will remain closed.
- North Beach: The contractor has demolished enough of the Pagoda Palace to reopen Powell Street between Columbus and Union starting Saturday, August 24. The traffic lane still may be narrowed at times. The 39 Coit will return to its regular route. Work will be in progress this Saturday, August 24, from 7 a.m. to 12 noon to off-haul materials from the site. Parking will be impacted in front of the Pagoda Palace property. The sidewalk in front of the property may be closed.
At these locations, current construction impacts are planned to continue until September 2:
- Northern SoMa (Market to Harrison): Two lanes of traffic will remain closed on 4th Street between Howard and Folsom. On 4th Street between Market and Stevenson, two traffic lanes will remain closed on the eastern side of the street.
- Chinatown: No construction planned.
- Union Square: Stockton Street between Geary and Ellis will remain closed to vehicle traffic. Ellis Street between Stockton and Powell will remain closed to westbound traffic.
We appreciate your patience and support while we build this essential upgrade to San Francisco's public transportation system.
-The Central Subway Team 
Tunnel boring machine Mom Chung is now completely underground, out of the excavation where she launched last month. This photo shows the back of the machine within the new tunnel. Southern SoMa
4th Street from Harrison to King/Berry
On 4th Street between Harrison and Bryant streets, the contractor has constructed a major excavation known as a launch box at the site where the Central Subway tunnel begins. After assembly of a tunnel boring machine (TBM) underground, tunneling started this summer. Assembly of a second TBM is now in progress.
Planned construction:
- Construct tunnel for southbound trains (TBM Mom Chung)
- Install conveyor and facilities for TBM Mom Chung
- Install and assemble TBM Big Alma
Traffic and pedestrian impacts:
- The two lanes on the east side of the street (left lanes for southbound traffic) will remain open to vehicle traffic except as described below.
- The block may close to traffic from 8 p.m. to 5:30 a.m. on weeknights and all day Saturday and Sunday. When the Giants have home games, the closure will start an hour after the game ends.
- The sidewalk on the west side of the block will remain closed; the sidewalk on the east side of the block will remain open.
- On Bryant Street at 5th Street, the left lane and several parking spaces will be closed.
Traffic and pedestrian controls are in place. For more information on construction impacts at this site, check out this blog post.
Construction at 4th and Market, shown here, finished up this week. Work will recommence a few months from now when the TBMs pass beneath this area.
Northern SoMa
4th Street from Market to Harrison
On 4th Street between Howard and Folsom streets, the contractor has constructed below-ground walls, called headwalls, at the site of the future Yerba Buena/Moscone Station. Water line work is now in progress. For more information on construction at this site, check out this blog post.
In addition, the contractor is performing ground improvement work (installation of compensation grout tubes) on 4th Street between Market and Stevenson. More information is available in this construction notice.
Planned construction (Market to Stevenson):
- Demobilize equipment
- Restore roadway
- Construction will resume when the tunnel boring machines pass beneath this area (approximately November).
Traffic and pedestrian impacts (Market to Stevenson):
- Two lanes on the eastern side of the street (near Ross) will be closed until the roadway has been restored
Planned construction (Howard to Folsom):
- Install and test water line
- Perform site restoration
Traffic and pedestrian impacts (Howard to Folsom):
- Two lanes of traffic will be closed on the eastern side of the block
- The sidewalk on the western side of the street will be narrowed
- The crosswalk crossing 4th Street on the north side of Folsom will remain closed
A drill excavates dirt at Stockton and Geary, the future site of the Union Square/Market Street Station. Union Square
Stockton Street from Market to Post
On Stockton Street between Geary and Ellis streets, the contractor is installing below-ground walls called headwalls at the site of the future Union Square/Market Street Station. In addition, ground improvement is underway on Ellis Street between Stockton and Powell streets.
Planned construction:
Stockton between Ellis and O'Farrell:
- Perform ground improvements
Stockton between O'Farrell and Geary:
- Install headwalls
Ellis between Stockton and Powell:
- Install ground improvement pipes in Ellis Street shaft
All blocks:
- The contractor will continue working two shifts on weekdays, from 6 a.m. to 12:30 a.m.
- On Saturdays, work hours will be 6 a.m. to 10 p.m.
Traffic, transit and pedestrian impacts:
- Stockton Street between Geary and Ellis is closed to all vehicles except emergency vehicles
- Ellis Street between Stockton and the Ellis-O'Farrell Garage (between Stockton and Powell) is closed to westbound traffic
- The 38/38L Geary may experience delays around Union Square
- Sidewalks on Stockton Street between Ellis and Geary will remain open, but they may be narrowed to facilitate construction
More information about construction at this site is available in this construction notice and this press release. 
This property on Washington Street is the future location of the Chinatown Station. Chinatown
Stockton Street from Sacramento to Broadway
No construction is planned to occur in Chinatown during the next 10 days. 
Inside the Pagoda Palace, saw through the metal that was reinforcing the walls of the Pagoda Palace. These and other demolished components will be hauled off site as demolition proceeds. North Beach
Powell Street from Union to Columbus
On private property at 1731-1741 Powell Street, the contractor is preparing to construct a walled excavation known as a retrieval shaft at the site where tunneling will end. The two tunnel boring machines will be removed from the ground at this location.
The first phase of construction at this site is the demolition of the Pagoda Palace. Check out this fact sheet for more details.
Planned construction:
- Demolish building from within property lines
- Construction hours are Monday to Friday, 7 a.m. to 3:30 p.m., though work may continue inside the building until 5 p.m.
- Work will be in progress on Saturday, August 24, from 7 a.m. to 12 noon. The contractor will be hauling materials from the site at this time.
Traffic, transit and pedestrian impacts:
- Starting Saturday, August 24, Powell Street between Union and Columbus will reopen to vehicle traffic at all times, though the traffic lane may be narrowed.
- Several parking spaces in front of the property will be impacted.
- The sidewalk in front of the property and the crosswalk crossing Powell Street at Columbus Avenue may be impacted. A temporary walkway will be in place around the construction zone while walkways are impacted.
- The Muni 39 Coit will resume its regular route.
Central Subway Construction Fast Facts
Project Alignment: 4th Street between Berry and Market streets; Stockton Street between Market Street and Columbus Avenue; Powell Street between Union Street and Columbus Avenue; Columbus Avenue between Powell and Filbert streets.
Transit Reroutes: The southbound 8X/8AX/8BX Bayshore Express, 30 Stockton, 45 Union/Stockton and 91 Owl Muni bus routes have been rerouted to accommodate construction in Union Square and SoMa. These reroutes will remain in effect throughout the duration of Central Subway construction. More information is available online here.
Contact Us: Should you have questions about construction or the Central Subway Project, don't hesitate to contact our team. You can reach us at central.subway@sfmta.com or by phone at 415-701-4371.
For More Information: The Central Subway team posts frequent project updates on a variety of social media outlets. To find out more about the project and construction progress, follow us on Facebook, Twitter, Instagram or Flickr, and check out our blog.
Construction schedules are subject to change.