T Third Street
The T Third Street is a Muni Metro line in San Francisco, California. It is the first new light rail line in San Francisco in more than half a century, and the first fully accessible line in the system. It is also the first true light rail line in the mostly streetcar Muni Metro system, as it operates mostly in a street median, rather than in mixed traffic.
Testing on the line took place in summer 2006, with limited service starting on January 13, 2007, and full service beginning on April 7, 2007. It runs along the newly constructed light-rail tracks on Third Street and Bayshore Boulevard in the Visitacion Valley, Bayview/Hunters Point, Dogpatch, and Mission Bay neighborhoods, connecting to the existing Muni Metro system along the southern Embarcadero and below Market Street, and replaced the 15 Third bus line.
In the future, the line may be extended to Caltrain's Bayshore Station (to which it was originally planned to run) and, in the other direction, to San Francisco's Washington Square in North Beach via Chinatown Central Subway alignment.
Current alignment — conjoined operation with K Ingleside
Following service changes on June 30, 2007, the T Third Street and the K Ingleside lines were spliced together in the Market Street Subway tunnel, resulting in a route from Balboa Park, through downtown, to Bayshore and Sunnydale. At West Portal Station, inbound K trains heading through downtown to Third Street change their signs to the T line; at Embarcadero Station, T trains heading through downtown and outbound to the Ingleside neighborhood change signs to the K line. Each train displays its ultimate destination. This system will continue in place until the Central Subway is operational.
Leaving the Market Street Subway at Ferry Portal heading south, the T Third follows The Embarcadero south of Market Street, then veers onto King Street in front of Oracle Park until it reaches the Caltrain station terminal. This portion of the Muni Metro rail line between the Embarcadero portal and the Caltrain terminal was built in 1998 and is utilized by an extension of the N Judah, which shares track with the T to the Caltrain terminal at 4th and King. From there the T turns south on Fourth Street, crossing the bridge over Mission Creek before joining Third Street for the majority of the route's length. It passes through Mission Bay where the UCSF Mission Bay branch is located, then continues on south through the Bayview and Hunters Point neighborhoods. Once both economically impoverished parts of the City, they have slowly experienced rehabilitation and rebuilding mainly helped by the new T line. At the intersection of Third and Jamestown Avenue, the T continues to run in both directions as it crosses U.S. Highway 101 (James Lick Freeway), although only Third Street is open to auto traffic northbound; likewise, southbound auto traffic is splintered to a southbound on ramp to Highway 101 and merges with San Bruno Avenue. From there the T follows Bayshore Boulevard (changed over from Third) for two more stations until it reaches its terminus at Sunnydale Station. A section of track follows one more block until stopped short at the Daly City limits.
All stations along this line feature high platforms, eliminating the need for the raising and lowering of entrance and exit steps characteristic of other Muni Metro lines. Stations south of Fourth and King feature short platforms that accommodate only two-car trains.
The T Third also uses the Muni Metro terminology in which an inbound train goes from West Portal to Embarcadero. This also means that an outbound T Third train runs from Sunnydale and out to the western neighborhoods via downtown. This is the reverse of other lines, as those lines have their outer termini on the southwest and west sides of the city, and those trains enter the subway from the west going inbound toward downtown.
The underground section of the line was closed west of Castro station from June 25 to August 24, 2018 due to the Twin Peaks Tunnel shutdown. On August 25, 2018, at the conclusion of the shutdown, Muni began running permanently two-car trains on the K/T line (as had been used east of Castro during the shutdown). The line was shut down from January 22, 2019 until April 1, 2019 for construction of a new platform at UCSF/Mission Bay station.
T-Third has been built in phases. The first phase extended rail service south to Sunnydale Station. The second phase, currently under construction, is also known as the Central Subway project, and will reroute T-Third north of the 4th and King Station. The future alignment once the second phase is complete will neither share right-of-way with, nor share identities with the K Ingleside, avoiding both King Street and the congested Market Street subway. The southern segment from Sunnydale to 4th and King Street will remain as-is, operating on street-level tracks in the median of Third Street and Bayshore Boulevard. After 4th and King, the line will cross King Street instead of turning onto it, and proceed to a new 4th and Brannan Station, and the line will then burrow to subsurface level at Bryant Street Portal, near where 4th passes under Interstate 80. Underground, the line will continue under Fourth Street, to Yerba Buena/Moscone Station, and then, after crossing Market Street, will turn slightly to continue under Stockton Street, continuing to Union Square/Market Station providing a transfer to Market Street Subway MUNI and BART lines before running underneath Stockton Street and terminating at Chinatown Station.
To complement the Central Subway, Muni is also constructing the Mission Bay Loop (MBL), an additional loop along the T Third line that would enable more frequent short-line service to the section of the line from Mission Bay through the Central Subway. MBL would connect the existing T Third tracks on 3rd Street to additional tracks along 18th Street, Illinois Street, and 19th Street to connect back to 3rd Street.
A proposed third phase would build an extension beyond Chinatown, including new stations at Washington Square in North Beach and Fisherman's Wharf. In preparation, the tunnels were bored past Chinatown Station, and the tunnel boring machines were extracted from the intersection of Powell and Columbus, near Washington Square. The SFMTA published a concept study in January 2015 on the feasibility of several options for phase 3. The report studied three main alignments: Columbus Ave, Powell St, or a loop line on Powell St, Beach St, and Columbus Ave. Both subway and surface options were studied for each alignment. The report found that the phase 3 project could improve transit trip time by at least 50% and would increase the ridership on the T Third by 55%. Project cost estimates ranged from $440 million to $1.4 billion depending on the design. In June 2018, the SFMTA kicked off Phase III by beginning to study alternative routes in detail in order to narrow down the options for a future environmental impact study.
A conceptual fourth phase has been advanced by SFMTA and transit advocates to further extend the line west of Fisherman's Wharf to the Presidio. However, since the Central Subway station platforms will be about 250 feet (76 m) long, enough to accommodate two-car trains, unlike the upper deck Market Street subway platforms which can accommodate four-car LRV trains, the projected ridership increase with a fourth phase Presidio extension would require the stations currently under construction to be rebuilt to three- or four-car trains.
Initially upon opening, the T Third was operated from Castro Station to Bayshore and Sunnydale. In the aftermath of the Muni Meltdown of 2007, the T Third was suspended from operating as a distinct line, in favor of being through-routed with the K Ingleside.
Diagrams of the various T Third Street routings over its history
The T Third operates seven days a week, beginning at 5 a.m. weekdays, 6 a.m. Saturdays and 8 a.m. Sundays, operating until 1 a.m. Headways on the route range from 1 to 30 minutes during the day, and from 12 to 90 minutes at night. Late night service is provided by the 91 Owl diesel bus line on Third Street, and by the N-Owl diesel bus line on King Street, The Embarcadero and most of Market Street. There is also a T-Owl diesel bus line that runs from Market Street and Van Ness Avenue to Bayshore Boulevard and Sunnydale. This line only operates on weekend mornings, between the times owl service stops and the underground subway stations open.
In 2018, Muni began running two-car trains on T Third to increase capacity.
Future service plans
Work is underway on the Mission Bay Loop project, which will extend rails around the block bounded by 3rd, 18th, Illinois, and 19th. The loop was originally designed in 1998 with the original routing of T Third, but was deferred due to insufficient funding; construction started in July 2016 and is anticipated to complete by Spring 2019. When the Central Subway and Mission Bay Loop projects are complete, Muni intends to split the T Third service into short-line and long-line services. The short-line service would run from Chinatown station to the Mission Bay Loop with planned 4 minute headways while the long-line service would run the full route from Chinatown to Sunnydale station at 7.5 minute headways. Another loop at 25th and Illinois is being planned to increase short-line service frequency between Downtown and Dogpatch.
Station and stop listing
outbound to inbound
|West Portal||West Portal||Sign change from K Ingleside inbound|
|Forest Hill||Forest Hill and Laguna Honda|
|Church||Duboce Triangle||*||*Connects with J Church on surface stop at 14th Street|
Connects with F Market & Wharves streetcar
|Van Ness||Civic Center and Tenderloin||Connects to F Market & Wharves|
|Civic Center||Civic Center||Connects to F Market & Wharves and BART|
|Powell||Financial District||Connects to F Market & Wharves and BART|
|Montgomery||Financial District||Connects to F Market & Wharves and BART|
|Embarcadero||Financial District||Changes to K Ingleside outbound|
Connects to F Market & Wharves and BART
Serves Ferry Building
|Folsom||Financial District||Connects to E Embarcadero|
|Brannan||South Beach||Connects to E Embarcadero|
|2nd and King||Mission Bay||Connects to E Embarcadero|
Serves Oracle Park
|4th and King||Mission Bay||*||Serves CalTrain; *Transfer made to E Embarcadero and N Judah via separate platform nearby|
|Mission Rock||Mission Bay|
|UCSF/Chase Center||Mission Bay||Serves the UCSF Mission Bay Campus and Chase Center|
|UCSF Medical Center||Mission Bay|
|Sunnydale||Visitacion Valley||Inbound terminus|
|Union Square/Market Street||Financial District||Underground pedestrian pathway to Powell Street station|
|4th and Brannan||SoMa|
- "TEP Route Data & Proposed Changes". San Francisco Municipal Transportation Agency (SFMTA). 2013. Retrieved 2013-12-15.
- Gordon, Rachel (July 26, 2006). "Third Street seeing streetcars / Test runs for light-rail project begin at last". San Francisco Chronicle. Retrieved 2013-12-15.
- Cabanatuan, Michael (January 12, 2007). "T-Third Muni line starts service Saturday". San Francisco Chronicle. Retrieved 2013-12-15.
- Gordon, Rachel (June 4, 2007). "T-Third line causing delays, so officials consider new routes". San Francisco Chronicle. Retrieved 2013-12-15.
- "KT-Ingleside/Third Street". San Francisco Municipal Transportation Agency (SFMTA). Retrieved 2013-12-15.
- "Twin Peaks Tunnel Improvements". San Francisco Municipal Transportation Agency. June 25, 2018. Archived from the original on June 26, 2018.
- von Krogh, Bonnie Jean (August 24, 2018). "Two-Car Trains Now Permanent on K/T Line" (Press release). San Francisco Municipal Transportation Agency.
- "T Third Bus Substitution". San Francisco Municipal Transportation Agency. Archived from the original on January 20, 2019.
- McMillan, Erin (March 29, 2019). "T Third Back In Action" (Press release). San Francisco Municipal Transportation Agency.
- Vega, Cecilia M. (20 February 2008). "S.F. Chinatown subway plan gets agency's nod". San Francisco Chronicle. Retrieved 10 March 2017.
- Rodriguez, Joe Fitzgerald (2018-07-23). "Cost for long delayed Muni 'loop' to boost Warriors train service jumps $1.4 million". San Francisco Examiner. Retrieved 2018-10-23.
- SFMTA (2013-05-06). Environmental Assessment for Mission Bay Transit Loop Project (PDF) (Report). Retrieved 2018-10-23.
- Cabanatuan, Michael (26 November 2014). "Extending S.F.'s Central Subway would draw riders, study says". San Francisco Chronicle. Retrieved 10 March 2017.
- T-Third – Phase 3 Concept Study (PDF) (Report). San Francisco Municipal Transportation Agency, Sustainable Streets Division. October 2014. Retrieved 10 March 2017.
- Rodriguez, Joe Fitzgerald (2018-06-13). "Planning begins for Central Subway extension to Fisherman's Wharf". San Francisco Examiner. Retrieved 2018-06-15.
- Bialick, Aaron (5 December 2014). "Extending the Central Subway: Why Stop at Fisherman's Wharf?". Streetsblog SF. Retrieved 10 March 2017.
- "Schedule & Route Maps – KT – (Muni (SFMTA)) Ingleside/Third Street – Metro: Inbound toward Sunnydale via Downtown. Outbound toward Balboa Park Station eff. Sept. 4 via Downtown and West Portal. No bikes". Transit.511.org. Retrieved 2013-12-15.
- Swan, Rachel (October 19, 2018). "The T line has never lived up to its promise. Coming upgrades may not be enough to help". San Francisco Chronicle. Retrieved 24 October 2018.
- "Mission Bay Loop". San Francisco Municipal Transit Agency. Retrieved 24 October 2018.
- Official project website
- Map of the line
- Official Map of the T Line in PDF
- Wilbur Smith Associates (1993). Bayshore Transit Study (Report). City and County of San Francisco, San Francisco Municipal Railway. Retrieved 10 March 2017.
- "Central Subway Extension: Phase III of the T Third Rail project". San Francisco Municipal Transit Agency. Retrieved 24 October 2018.