Below, sparks fly as a worker uses an angle grinder to smooth edges of a steel bracket inside the north concourse, where temporary steel reinforcing is being installed.

An underground view of the southeast corner of the Union Square Garage where construction of the north station entrance is ongoing.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

Sections of pipe are stacked for installation on 4th Street north of Townsend

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Construction at the Yerba Buena|Moscone station continues. Construction of the mezzanine floor is progressing and crews are building concrete forms for the final section. Excavation continues in the headhouse. Workers are installing a water line at 4^th Street and Howard.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.

The Central Subway Team

Waterproofing vinyl and a slab of concrete now cover a new section of roof deck on the north side of the O’Farrell and Stockton intersection.

Underground, workers drill inside the station box between Geary and O’Farrell streets.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

Construction workers supervise excavation activity under Stockton Street.

A view from inside the southeast corner of the Union Square Garage, as workers demolish floors to prepare for construction of the north station entrance.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

Steel supports are installed for the roof deck of the station box on Stockton Street

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Starting Monday night, February 29 through Monday, March 7, the contractor will be performing night work to pothole at the intersection of Stockton Street and Washington Street. Hours of construction are 10p.m. to 5a.m.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.

Demolition work at the south east corner of the Union Square Garage.

A view from inside the north concourse, north of Geary Street, where a small jackhammer is being used to smooth the walls during excavation.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

The much-appreciated plaza features a nightly light show that is projected onto the Macy’s Men’s building, featuring San Francisco landmarks and holiday themed-images.

Shoppers, pedestrians, visitors and locals of all ages can enjoy the open space, festive decorations and special seating in the plaza through the first of January.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

Slender metal stakes and a long strip of adhesive affixed to the underside of the turf joints keep everything together as workers set up for the 2015 Winter Walk

Happy Thanksgiving!  The Central Subway team wishes San Francisco a happy and healthy 2015 holiday season.

Come and celebrate the season with the second annual Union Square Winter Walk. Beginning Friday, November 27 and continuing through New Year’s Day, Stockton Street between Ellis and Geary will be transformed into a winter wonderland.

Last year, the Winter Walk was a great success and we have more holiday treats and surprises for the public this year. Off the Grid food trucks will be there to satisfy hungry shoppers.  A nightly light show will dazzle the Winter Walk.  Sample Ghirardelli chocolate on Saturdays. There will be performances by carolers and other entertainers.  These are just some of the delights available for your pleasure in the Winter Walk. For more information see #WinterWalkSF.

We hope to see you all at the Winter Walk.  Thanks to the entire public for your cooperation in 2015 as we build a new subway for our city.

Here are some photos from last year’s Winter Walk:

The Winter Walk is a great place for shoppers to relax after a busy day of shopping

Shoppers enjoying  the 2014 Winter Walk

Off the Grid trucks were stationed in the Winter Walk 2014. They are returning this year to provide treats to hungry shoppers

Crews build a new ramp inside the Union Square Garage located at the southeast corner of Union Square.

Work is taking place on all four levels of the garage.  This work includes laying rebar, constructing concrete forms and building a wall.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

Rendering of the underground Union Square | Market Street station. This station will feature a concourse that will allow T Third passengers to easily access other Muni lines and BART

There is a lot of activity as construction moves forward in Union Square.  At the corner of Geary and Stockton, a small portion of the Union Square Garage is being demolished to allow for the construction of the north entrance to the Union Square. The entrance will open to the sidewalk of Geary and Stockton.

Construction on the roof of the north concourse is ongoing.  The work is being done in sections on Stockton near Maiden Lane and Geary.  Workers have excavated soil to the roof level, installed steel beams and corrugated steel sheets, and poured concrete.

Work on the south concourse to the Union Square | Market Street station is also underway.   At the intersection of Ellis and Stockton, crews are removing soil and reconstructing the currently closed Ellis Street entrance to Powell/BART/Muni station to also accommodate the Union Square | Market Street Station.

Throughout the construction area, drilling and compensation grouting are being performed.  In compensation grouting, a concrete-like solution is injected under pressure into a pre-drilled hole.  This helps to harden and stabilize the soil under surrounding buildings and structures.

All of the work has a great benefit.  Not only will the Union Square | Market Street Station give residents and tourists easy access to Union Square, it will also have a walk way connecting passengers easily to other Muni lines and BART.

Here are some photos of the construction:

A worker adds a section of drill shaft during compensation grouting operations south of Geary

Looking south down the future south concourse, with the access shaft north of Ellis in the foreground

Structural walls are being constructed inside the south concourse of the Union Square/Market Street Station