Third Street Light Rail Project
| Company type | Public transit project |
|---|---|
| Industry | Public transportation |
| Founded | 2006 |
| Headquarters | San Francisco , United States |
Area served | Southeastern neighborhoods of San Francisco (Bayview-Hunters Point, Visitacion Valley) |
| Products | Light rail transit service (T Third Street Metro line) |
The Third Street Light Rail Project enhanced the Muni Metro network in San Francisco by linking the downtown area with the historically underserved southeastern neighborhoods of Bayview-Hunters Point and Visitacion Valley. The construction was completed toward the end of 2006, followed by non-revenue weekend operations starting January 13, 2007. Full revenue service officially commenced on April 7, 2007. This new T Third Street Metro line replaced the former 15 Third bus route, which previously connected the San Francisco 4th and King Street station along Third Street and Bayshore Boulevard heading southeast.
History
The 1993 Bayshore Transit Study conducted by San Francisco Municipal Railway established seven primary objectives aimed at enhancing transit services within the Bayshore corridor. These goals focused on increasing ridership, fostering economic growth, improving environmental conditions, integrating with broader regional transportation systems, ensuring financial viability, accelerating project delivery, and promoting equitable access to transit.
The study examined nine different options ranging from trolley coaches to expanding Muni Metro light rail. Among these were two light rail alternatives that proposed extending service southward from the Financial District to Caltrain's Bayshore Station via Third Street. Additional future extensions under consideration included routes through Hunter's Point, Little Hollywood (toward Candlestick Park), and along Bayshore and Geneva avenues to reach Balboa Park station.
Initially estimated at $667 million, the project's budget increased by $120 million as of July 2006.
Route
The T Third line originates at Chinatown station, proceeding through the Central Subway to arrive at the Caltrain Depot located at 4th and King streets before continuing along Third Street. With this new rail service in place, the 15-Third bus route was discontinued. To maintain coverage in areas not served by the rail extension—such as City College and Fisherman's Wharf—the 8-Bayshore bus route was extended accordingly.
Although originally intended to connect directly with the Bayshore Caltrain Station, this linkage has been postponed due to Caltrain’s 2004 CTX project relocating Bayshore Station into San Mateo County without Muni’s prior knowledge. As a result, the southern endpoint currently remains at Sunnydale Station along Bayshore Boulevard.
Features
The project introduced eighteen newly built stations equipped with either island platforms or side platforms featuring raised platform heights to enable level boarding, comparable to those on the N Judah line along the Embarcadero.
Improvements also encompassed repaving Third Street, installing modern street lighting, planting palm trees, and refurbishing sidewalks. Station designs include unique marquee poles adorned with sculptures or mobiles as distinctive visual elements.
Light rail vehicles (LRVs) primarily operate within a dedicated center-street right-of-way designed to minimize traffic interference and enhance travel speed. Exceptions to this exclusive lane include sections such as the 4th Street Bridge and a stretch within the Bayview commercial district where mixed traffic is maintained to preserve parking availability for local businesses.
Throughout the corridor, transit signal priority technology is employed to grant LRVs preferential green lights at intersections, thereby reducing travel times between stops.
Further expansion
The Third Street Light Rail Project represents the initial stage of a broader Muni Metro development plan. The subsequent phase—known as the Central Subway—reroutes T Third trains away from the shared tracks with N Judah north of 4th and King. This segment runs above ground from the Caltrain terminal at 4th and King to a newly established station at 4th and Brannan station, then continues underground with stops at Yerba Buena/Moscone station, Union Square/Market Street station, ultimately concluding at Chinatown station. Additionally, this phase incorporates a short-turn operation through the recently completed Mission Bay Loop, finished in 2019 at an investment of $10.2 million, improving transit access to the Chase Center. The integration of T Third trains into the Central Subway began on January 7, 2023.
Back in 2009, plans surfaced to extend the Central Subway beyond Chinatown, traversing North Beach and Fisherman's Wharf, with a route passing by Pier 39. This extension could potentially utilize a historic steam railroad tunnel located beneath Fort Mason, terminating at The Presidio. These proposals were officially outlined in 2014 as phase three (extension toward Fisherman's Wharf) along with a conceptual phase four (further westward expansion to the Presidio). Formal planning efforts for this northern extension commenced in late 2018, featuring community outreach and an Alternatives Study scheduled for completion by late 2019.