A message from SFMTA Director of Transportation Edward D. Reiskin
With much accomplished last year and even more progress on the horizon, the Central Subway Project is off to a busy and productive start to 2013. We have new names for the project’s two tunnel boring machines, a mesmerizing new artwork for the 4th and Brannan Station, a new plan for construction in North Beach, and significant progress preparing for tunneling. With construction of the subway tunnels, stations and tracks scheduled to begin this year, we are looking forward to continued advancement toward the completion of this essential extension of Muni’s T Third Line.
The Central Subway’s tunnel boring machines (TBMs) will be named Big Alma and Mom Chung, after historic San Francisco women. The public selected the names in an online poll held earlier this year. The state-of-the-art, 300-foot-long machines will excavate and construct the two subway tunnels, one for northbound trains and one for southbound trains, beginning later this year. Thanks to everyone who voted for participating in this exciting and important part of tunneling tradition.
In partnership with the San Francisco Arts Commission, we have selected a new artwork to decorate the 4th and Brannan Station, the project’s only surface-level station. The artwork, by Bay Area artist Moto Ohtake, will interact with the environment by responding to the city’s variable wind conditions. It was designed to reflect the community of San Francisco as a microcosm and to evoke a contemplative experience for Muni customers.
In North Beach, we have been working to respond to community concerns about Central Subway construction by relocating the construction site where we will remove the TBMs from the ground. The retrieval site, previously planned for Columbus Avenue near Washington Square Park, is now planned to be located at the site of the old Pagoda Palace Theater on Powell Street. We thank the community, Mayor Lee, Supervisor David Chiu, numerous city agencies, and the property owner for their support and cooperation in working to achieve this change.
Construction continues to move forward, with significant progress in Union Square and SoMa. With five active construction sites along Stockton Street and 4th Street, tunnel preparation is well underway. To find out more about Central Subway construction, sign up for our weekly construction updates by visiting: http://eepurl.com/oOs-b
Thank you for your continued interest in the Central Subway Project and public transportation in San Francisco. 
Tunnel boring machine Mom Chung in the factory. Photo courtesy the Robbins Company.
Introducing Mom Chung and Big Alma
We are excited to introduce Big Alma and Mom Chung, the tunnel boring machines (TBMs) that will excavate and construct the Central Subway tunnels. Named after “Big Alma†de Bretteville Spreckels, and Dr. Margaret “Mom†Chung, the machines will begin tunneling later this year, starting in SoMa and heading north under 4th Street and Stockton Street through Union Square, Chinatown and North Beach.
The first of the machines, Mom Chung, is expected to arrive in San Francisco by May. The 300-foot-long machine will be assembled within the launch box on 4th Street between Harrison and Bryant streets and will start building the tunnel for southbound trains about two months later. Big Alma will arrive soon after to construct the northbound tunnel.
As tunneling proceeds, updates about the TBMs, including photos of the machines and the tunnels, will be posted on Twitter at the usernames BigAlmatheTBM and MomChungtheTBM. You can learn more about them on our website, at www.centralsubwaysf.com/tbm-name.
4th & Brannan Station Art
The San Francisco Arts Commission’s Public Art Program is managing the integration of a dynamic contemporary artwork at the 4th and Brannan Station. The work, “Microcosmic†by artist Moto Ohtake, is a large-scale kinetic sculpture that will interact with the environment by responding to the city’s variable wind conditions. The sculpture will be installed on the upper section of the platform’s 40-foot-tall marquee pole (rendering shown at left).
Mr. Ohtake draws his inspiration from the natural world on both macro- and microscopic levels. Microcosmic was designed to reflect the community of San Francisco as a microcosm and to evoke a contemplative experience. The sculpture will be comprised of two large circular wings outfitted with 31 rotating components, including interlocking loops in a range of sizes. The various components will move in gyroscopic circular motions. They will be angled differently to create opposing rotations under the same wind conditions, allowing viewers to experience an infinite number of movement combinations in response to changes in weather patterns.
Born in Japan, Mr. Ohtake received his Master of Fine Arts in sculpture from the San Francisco Art Institute. His artwork can be seen in the public collections of Santa Cruz and Stockton, at the Atlanta Botanical Garden in Atlanta, Ga., and in Dublin, Ireland, and Tokyo, Japan. Mr. Ohtake is an instructor of sculpture and 3-D design at de Anza College in Cupertino, California.
Top: A rendering of Microcosmic
Bottom: Artist Moto Ohtake 
Welcoming the Year of the Snake
In February the Central Subway team helped welcome the Year of the Snake at the Chinese New Year Parade & Festival in Chinatown. At the festival, members of the Central Subway team answered questions about the project and distributed souvenirs to attendees. Program Director John Funghi marched in the parade, carrying a Central Subway banner along the parade route through the Financial District, Union Square and Chinatown.
Thanks to everyone who stopped by our booth and celebrated the Year of the Snake with us. Gung hay fat choy from the Central Subway team! 
Construction Update
Central Subway crews are preparing for tunneling at five sites along the project alignment in SoMa and Union Square.
The largest site, on 4th Street between Harrison and Bryant streets, is where tunneling will commence this year. Crews are completing construction of a major excavation almost as large as the block. The project’s two tunnel boring machines will be assembled one at a time inside the excavation before they begin building the new subway tunnels.
At the sites of the future Yerba Buena/Moscone Station and Union Square/Market Street Station, crews are building underground walls that will be incorporated into the stations. The TBMs will excavate through the walls as they pass beneath 4th Street and Stockton Street.
In addition, ground improvement work is underway at two sites on 4th Street and on Ellis Street.
Above: Inside the tunnel launch box
Top right: Rebar installation on 4th Street
Bottom right: Ground improvement on 4th Street 
The Pagoda Palace, shown here, will be demolished to help clear the way for TBM extraction in North Beach.
TBM Retrieval Site Relocated to Pagoda Palace
The retrieval site for the Central Subway’s tunnel boring machines (TBMs) is planned to be relocated from Columbus Avenue to the Pagoda Palace at 1731-1741 Powell Street. SFMTA staff and multiple city agencies worked to relocate the retrieval site over the past few months in response to concerns about construction and traffic disruption associated with the original plan.
To finalize the site change, the SFMTA has signed a lease agreement with the owner of the Pagoda Palace property and gained the necessary city approvals to allow a previously approved development project to proceed after the TBMs are removed. The two-year lease allows the Agency to demolish the existing building, construct a retrieval shaft and remove the TBMs once they arrive in North Beach. The Agency is also pursuing environmental clearance for the change from the Federal Transit Administration.
We thank the community, Mayor Lee, Supervisor David Chiu, numerous city agencies, and the property owner for their support and cooperation in achieving this agreement.