Central Subway (San Francisco)

Central Subway
A test train at Union Square/Market Street in November 2022
Overview
Other name(s)Third Street Light Rail Project Phase 2
Line
LocationSan Francisco, California
SystemMuni Metro
Start4th Street portal 37°46′48″N 122°23′55″W / 37.7799°N 122.3985°W / 37.7799; -122.3985
EndChinatown
No. of stations3 (plus 1 surface as part of extension project)
Operation
Work begun2012
OpenedNovember 19, 2022 (2022-11-19) (weekend-only shuttle service)
January 7, 2023 (2023-01-07) (full service)
OwnerSan Francisco Municipal Transportation Agency
OperatorSan Francisco Municipal Railway
CharacterLight rail
Technical
Line length1.7 mi (2.74 km)
No. of tracks2
Track gauge4 ft 8+12 in (1,435 mm) standard gauge
ElectrifiedOverhead line, 600 V DC
Route map
Central Subway highlighted in red
provision for future extension
Chinatown
Union Square/​Market Street
Powell
 
Yerba Buena/​Moscone
4th and Brannan
4th and King

The Central Subway is a Muni Metro light rail tunnel in San Francisco, California, United States. It runs between Chinatown station in Chinatown and a portal in South of Market (SoMa), with intermediate stops at Union Square/Market Street station in Union Square and Yerba Buena/Moscone station in SoMa. A surface portion runs through SoMa to connect to the previously existing T Third Street line at 4th and King station.

The project was initiated after the Embarcadero Freeway was demolished following the 1989 Loma Prieta earthquake, as activist Rose Pak "almost single-handedly persuaded the city to build" the Central Subway to compensate Chinatown for the loss of the fast cross-town connection. Originally set to open in late 2018, the subway initially opened with a weekend-only shuttle service between Chinatown station and 4th and Brannan station on November 19, 2022. Full service as part of the T Third Street line began on January 7, 2023. With the addition of the Central Subway, the T Third Street line is projected to become Muni Metro's highest ridership line by 2030.

The budget to complete the Central Subway was $1.578 billion. The project was funded primarily through the Federal Transit Administration’s New Starts program. In October 2012, the FTA approved a Full Funding Grant Agreement, the federal commitment of funding through New Starts, for the Central Subway for a total amount of $942.2 million. The Central Subway was also funded by the State of California, the Metropolitan Transportation Commission, the San Francisco County Transportation Authority and the City and County of San Francisco.