The video shows TBM Mom Chung breaking into the water-filled retrieval shaft last June. The water is drained from the shaft for the arrival of TBM Big Alma. The departure of the machines comes next as workers remove both TBMs, piece by piece, over several months. The retrieval shaft site was restored and vacated in January 2015.

A metal cover was installed as the final step in restoring the site.

For more information about the project and construction progress, follow us on Facebook, Twitter, Flickr, YouTube and check out our project website.

People enjoy “Winter Walk SF” on Stockton Street in Union Square. More information is available on our blog.

Project Advancements

December 6 – December 15, 2014

During the next 10 days, Central Subway work continues at sites in SoMa, Union Square, Chinatown and North Beach. This post contains brief updates about recent construction activities and a look-ahead for what to expect in each neighborhood. For more detailed information, click here or on the links below. You can also find construction, traffic detour, and Muni impact information on our project Google Map.

Construction work on Stockton Street in Union Square has paused for the holiday season. Work within the station sites, underground work, and night work has continued. See your neighborhood section below for details.

Construction schedules may change due to unforeseen conditions. We encourage the public to follow traffic and pedestrian notifications posted at the work sites.

Southern SoMa (Harrison to King): Construction crews are relocating and installing new utilities along 4th Street from Harrison to King streets.

• At the intersection of 4th and Brannan streets, sewer line work is scheduled for Dec. 8 to Dec. 12.
  • Night work hours from 10 p.m. to 7 a.m.
• On 4th Street between Harrison and Bryant streets, construction of the portal continues.
  • Closure of this section of 4th Street through the end of February 2015.

Northern SoMa (Market to Harrison): Construction crews are building walls along 4th Street between Howard and Folsom streets.

• Temporary closure of covered sidewalk along 4th Street from Howard to Clementina streets from 8 p.m. Dec 8 to 5 p.m. Dec 12.
  • Pedestrians may access Clementina Street from 5th Street.

Union Square: Construction crews have converted Stockton Street between Ellis Street and Geary Boulevard into a holiday plaza called “Winter Walk SF.”

• On Ellis Street between Stockton and Powell streets, pile installation to construct underground station walls.
  • Night work hours from 10 p.m. to 6 a.m.

Chinatown: Construction crews are building station walls and installing new utilities on Stockton Street between Sacramento and Washington streets.

North Beach: Construction crews are restoring the retrieval shaft site.

We thank the businesses, residents, shoppers, and commuters of San Francisco for their continued engagement with this significant investment in the extension of our public transportation system. When opened in 2019, the Central Subway will provide a much-needed connection between major employment, retail, cultural and residential areas of the city.

Two workers clean a hydromill at the future Chinatown Station location. When opened in 2019 this station will increase transportation options.

During the next 10 days, Central Subway work continues at sites in SoMa, Union Square, Chinatown and North Beach. This post contains brief updates about recent construction activities and a look-ahead for what to expect in each neighborhood. For more detailed information, click here or on the links below. You can also find construction, traffic detour, and Muni impact information on our project Google Map.

Check out the new project construction video on YouTube posted here.

Construction schedules may change due to unforeseen conditions. We encourage the public to follow all traffic and pedestrian notifications posted at the work sites.

Southern SoMa (Harrison to King): Construction crews are relocating and installing new utilities along 4th Street from Harrison to King streets.

• At the intersection of 4th and Harrison streets, work on utilities is scheduled to start Monday, Oct. 20.
  • Two traffic lanes will remain open Monday to Friday, 7 a.m. to 5 p.m.
  • Access to Interstate 80 freeway may be limited on some evenings between 8 p.m. and 5 a.m.
• On 4th Street between Bryant and Brannan streets, installation of a sewer line continues.Two traffic lanes will remain open Monday to Friday, 7 a.m. to 3:30 p.m.

Northern SoMa (Market to Harrison): Construction crews are building walls and replacing a water line along 4th Street between Howard and Folsom streets.

• Tentative: Along 4th Street between Folsom and Harrison streets, sewer line replacement to start Oct. 28.

Union Square: Construction crews are excavating the site, building station walls and relocating utilities on Stockton Street between Ellis Street and Maiden Lane.

Chinatown: Construction crews are building station walls and installing new utilities on Stockton Street between Sacramento and Washington streets.

North Beach: Construction crews continue to restore the retrieval shaft site.

We thank the businesses, residents, shoppers, and commuters of San Francisco for their continued engagement with this significant investment in the extension of our public transportation system. When opened in 2019, the Central Subway will provide a much-needed connection between major employment, retail, cultural and residential areas of the city.

The cutter head of tunnel boring machine (TBM) Mom Chung can be seen in the background as workers disassemble the shield of TBM Big Alma.

During the next 10 days, Central Subway work continues at sites in SoMa, Union Square, Chinatown and North Beach. This section contains brief updates about what is happening in each neighborhood. For more detailed information click here or on the links below. You can also find construction, traffic detour, and Muni impact information on our project Google Map. For safety reasons, we encourage the public to follow all traffic and pedestrian notifications posted at the work sites.

Southern SoMa (Harrison to King/Berry): Potholing for utilities continues next week on 4th Street between Bryant and King. On Brannan between 4th and 5th Streets, work on utilities continues. Temporary walkways are in place around the construction zones.

Northern SoMa (Market to Harrison): At 4th and Folsom, work to build the Yerba Buena/Moscone Station continues. This includes construction of the station walls within the work site and water line replacement at the intersection of 4th and Folsom. Until Monday, July 28, 4th Street from Howard to Folsom streets will have one traffic lane. This area will continue to have a lane reduction overnight from 7 p.m. to 5 a.m.

Union Square: Stockton Street between Ellis and Geary is closed to vehicular traffic to allow for construction of the Union Square/Market Street Station. Work is underway for pile installation to construct the station walls. For the month of July, Stockton Street between Post and Geary will be closed to vehicular traffic. Please use alternate routes and follow construction signs.

Pile installation takes place at the southwest intersection of Stockton and O’Farrell streets until August 18. One lane of travel will be open. Expect delays and please use alternative routes.

Muni service impact:
Until August 1, the bus stop at Geary and Stockton will be temporarily discontinued. Please board bus at Geary and Powell. Please check back on our weekly Construction Update for the most current information on the re-opening of this stop.

Chinatown:  The contractor started station wall construction at the future station site and on the adjacent section of Washington Street. Work to replace high pressure water pipeline and install new fire hydrant on Washington is ongoing. A section of the sidewalk at the northeast corner of the Washington and Stockton intersection will be demolished in order to install a new fire hydrant.

North Beach: Work continues at 1731-1741 Powell. Sustainable Streets is constructing bulbs on Columbus Avenue between Filbert and Union streets, and widening the sidewalk on both sides of the street for this block. Street restoration work is expected to be completed by the end of August. More information is available in this notice.

We thank the businesses, residents, shoppers, and commuters of San Francisco for their continued engagement with this significant investment in the extension of our public transportation system.

On Wednesday, June 11, tunnel boring machine Big Alma joined her sister TBM Mom Chung to break through the concrete wall of the North Beach retrieval shaft.

During the next 10 days, Central Subway work will continue at sites in SoMa, Union Square, Chinatown and North Beach. This section contains brief updates about what is happening in each neighborhood. For more detailed information, click here or on the links below. We also post construction, traffic detour and Muni impact information on our project Google Map.

Southern SoMa (Harrison to King/Berry): Potholing for utilities will continue next week on 4th Street between Bryant and King. A temporary walkway is in place around the construction zone.

Northern SoMa (Market to Harrison): At 4th and Folsom, work to build the Yerba Buena/Moscone Station continues. This will include construction of the station walls within the work site and water line replacement at the intersection Fourth and Folsom. Night work is planned for these activities.

Union Square: Stockton Street between Ellis and Geary is closed to vehicular traffic and partial closure to vehicular traffic between Geary to Post to allow for construction of the Union Square/Market Street Station. Work is underway for pile installation to construct the station walls. Construction hours will be Monday to Saturday from 7 a.m. to 11 p.m. Beginning May 30 to July 25, the bus stop at Geary and Stockton will be temporarily be closed every Friday at 10 p.m. through the weekend. Service will resume every Monday at 4a.m. Muni service for this location will temporarily stop Mondays through Thursdays from 8 p.m. to 4 a.m.

Chinatown:  The contractor has started station wall construction within the future station site and on the adjacent section of Washington Street.

North Beach: Work will continue at 1455 Stockton and 1731-1741 Powell. Roadway and sidewalk restoration on Columbus and Union will continue and is expected to be completed by the 3^rd quarter of 2014.

We appreciate your patience and support while we build this essential upgrade to San Francisco’s public transportation system.

-The Central Subway Team

On Monday, June 2, tunnel boring machine Mom Chung broke through the concrete wall of the retrieval shaft, ending excavation of the southbound tunnel. Staff were on hand to celebrate.

During the next 10 days, Central Subway work will continue at sites in SoMa, Union Square, Chinatown and North Beach. This section contains brief updates about what is happening in each neighborhood. For more detailed information, click here on the links below. We also post construction, traffic detour and Muni impact information on our project Google Map.

Southern SoMa (Harrison to King/Berry): Potholing for utilities will continue next week on 4th Street between Bryant and King. A temporary walkway is in place around the construction zone. At the tunnel launch box on 4th Street between Harrison and Bryant, tunneling continues with both TBMs.

Northern SoMa (Market to Harrison): At 4th and Folsom, work to build the Yerba Buena/Moscone Station continues. This will include construction of the station walls within the work site and water line replacement at the intersection Fourth and Folsom. Night work is planned for these activities.

Union Square: Stockton Street between Ellis and Geary is closed to vehicular traffic and partial closure to vehicular traffic between Geary to Post to allow for construction of the Union Square/Market Street Station. Work is underway for pile installation to construct the station walls. Construction hours will be Monday to Saturday from 7 a.m. to 11 p.m. Beginning May 30 to June 23, the bus stop at Geary and Stockton will be temporarily be closed every Friday at 10 p.m. through the weekend. Service will resume every Monday at 4a.m. Muni service for this location will temporarily stop Mondays through Thursdays from 8 p.m. to 4 a.m.

Chinatown:  The contractor has started station wall construction within the future station site and on the adjacent section of Washington Street.

North Beach: Work will continue at 1455 Stockton and 1731-1741 Powell. Sewer, roadway and sidewalk restoration on Columbus and Union will continue and is expected to be completed by the 3^rd quarter of 2014.

We appreciate your patience and support while we build this essential upgrade to San Francisco’s public transportation system.

-The Central Subway Team

The first tunnel boring machine (TBM) will be arriving at the extraction pit soon. The contractor has filled the retrieval shaft with water to balance pressure on the face of the machine.

During the next 10 days, Central Subway work will continue at sites in SoMa, Union Square, Chinatown and North Beach. This section contains brief updates about what is happening in each neighborhood. For more detailed information, click here or on the links below. We also post construction, traffic detour and Muni impact information on our project Google Map.

Southern SoMa (Harrison to King/Berry): Potholing for utilities will continue next week on 4th Street between Bryant and King. A temporary walkway is in place around the construction zone. At the tunnel launch box on 4th Street between Harrison and Bryant, tunneling continues with both TBMs.

Northern SoMa (Market to Harrison): At 4th and Folsom, work to build the Yerba Buena/Moscone Station continues. This will include construction of the station walls within the work site and water line replacement at the intersection Fourth and Folsom. Night work is planned for these activities. At 4^th and Jessie, crew will be drilling and installing casing underneath 4^th Street.

Union Square: Stockton Street between Ellis and Geary is closed to vehicular traffic and partial closure to vehicular traffic between Geary to Post to allow for construction of the Union Square/Market Street Station. Work is underway for pile installation to construct the station walls. Construction hours will be Monday to Saturday from 7 a.m. to 11 p.m. Beginning May 30 to June 23, the bus stop at Geary and Stockton will be temporarily be closed every Friday at 10 p.m. through the weekend. Service will resume every Monday at 4a.m. Muni service for this location will temporarily stop Mondays through Thursdays from 8 p.m. to 4 a.m.

Chinatown:  The contractor has started station wall construction within the future station site and on the adjacent section of Washington Street.

North Beach: Work will continue at 1455 Stockton and 1731-1741 Powell. Sewer, roadway and sidewalk restoration on Columbus and Union will continue and is expected to be completed by the 3^rd quarter of 2014.

We appreciate your patience and support while we build this essential upgrade to San Francisco’s public transportation system.

At the intersection of Ellis and Stockton, the tunneling contractor has restored this work zone and handed it over to the station contractor.

During the next 10 days, Central Subway work will continue at sites in SoMa, Union Square, Chinatown and North Beach. This section contains brief updates about what is happening in each neighborhood. For more detailed information, click here or on the links below. We also post construction, traffic detour and Muni impact information on our project Google Map.

Southern SoMa (Harrison to King/Berry): Potholing for utilities will continue next week on 4th Street between Bryant and King. A temporary walkway is in place around the construction zone. At the tunnel launch box on 4th Street between Harrison and Bryant, tunneling continues with both TBMs. Three lanes of the I-80 off-ramp at 4th and Bryant may be closed Tuesday and Wednesday from 12 a.m. to 5 a.m. One lane of the I-80 off-ramp at 4th and Bryant may be closed Monday from 10 a.m. to 3 p.m.

Northern SoMa (Market to Harrison): At 4th and Folsom, work to prepare for the Yerba Buena/Moscone Station continues. This will include demolishing the roadway within the construction zone to prepare to construct underground station walls at 4th and Folsom at night. At 4^th and Jessie, crews are potholing for utilities and will be installing a manhole in the next few weeks.

Union Square: Stockton Street between Ellis and Geary is closed to vehicular traffic and partial closure to vehicular traffic between Geary to Post to allow for construction of the Union Square/Market Street Station. Work is underway to excavate material before constructing station walls. Construction hours will be Monday to Friday from 7 a.m. to 11 p.m.

Chinatown:  The contractor has started station wall construction within the future station site and on the adjacent section of Washington Street.

North Beach: Work will continue at 1455 Stockton and 1731-1741 Powell. Sewer, roadway and sidewalk restoration on Columbus and Union will continue and is expected to be completed by the 3^nd quarter of 2014.

We appreciate your patience and support while we build this essential upgrade to San Francisco’s public transportation system.

Crews demolishing and removing underground obstacles using rotary drill rigs and steel casings to keep the soil from caving in.

During the next 10 days, Central Subway work will continue at sites in SoMa, Union Square, Chinatown and North Beach. This section contains brief updates about what is happening in each neighborhood. For more detailed information, click here or on the links below. We also post construction, traffic detour and Muni impact information on our project Google Map.

Southern SoMa (Harrison to King/Berry): Potholing for utilities will continue next week on 4th Street between Bryant and King. A temporary walkway is in place around the construction zone. At the tunnel launch box on 4th Street between Harrison and Bryant, tunneling continues with both TBMs.

Northern SoMa (Market to Harrison): At 4th and Folsom, work to prepare for the Yerba Buena/Moscone Station continues. This will include demolishing the roadway within the construction zone to prepare to construct underground station walls at 4th and Folsom at night.

Union Square: Stockton Street between Ellis and Geary is closed to vehicular traffic and partial closure to vehicular traffic between Geary to Post to allow for construction of the Union Square/Market Street Station. Work is underway to excavate material before constructing station walls. Construction hours will be Monday to Friday from 7 a.m. to 11 p.m.

Chinatown:  The contractor has started station wall construction within the future station site and on the adjacent section of Washington Street.

North Beach: Work will continue at 1455 Stockton and 1731-1741 Powell. Sewer, roadway and sidewalk restoration on Columbus and Union will continue and is expected to be completed by the end of April.

We appreciate your patience and support while we build this essential upgrade to San Francisco’s public transportation system.

The front page of our new project brochure features photos of the neighborhoods and local destinations the Central Subway will connect.

Reducing travel times. Improving San Francisco’s transportation network. Connecting bustling neighborhoods, premier commercial districts, world-renowned tourist destinations and a burgeoning technology and digital-media hub. The Central Subway – a rapid, emission-free alternative to crowded buses and congested city streets – will do all this and more when it opens to the public in 2019.

Learn more about the Central Subway and its many benefits in our new project brochure. It includes key information about how the Central Subway will improve San Francisco’s public transit system, connect local communities and invest in San Francisco, as well as a brief history of the project’s strong local support.

Download the brochure here and share it with friends, family, coworkers, fellow transit advocates and others interested in finding out about more this important investment in San Francisco’s transportation infrastructure. It is also available in Chinese.