Since launching in early 2021, the Link21 project to create a new train tunnel across the San Francisco Bay has offered grand plans but few specifics.
But now, that’s begun to change. This week, the project’s planners released the most detailed maps yet showing the possible route of the train tunnel — or tunnels, as the case may be.
At a meeting of the governing body of the Capitol Corridor, which is jointly planning the Link21 project alongside BART, planners unveiled two conceptual maps.
One shows BART and regional rail trains — like Capitol Corridor or Caltrain — traveling side by side in a shared alignment from Oakland and Alameda to the Salesforce Transit Center in San Francisco.
Map showing the possible train tunnel routes of Link21.
The other design shows two tunnels, one for BART trains and one for regional rail trains. The regional rail tunnel would travel directly from Oakland to the Salesforce Transit Center, while the BART tunnel would travel from Alameda to Mission Bay before veering north to connect to the Market Street subway.
Otherwise, the two design concepts share many similarities.
Both plans hint at the possibility of a BART subway down Geary Boulevard, with the blue arrows pointing west from downtown San Francisco and labeled as a “possible extension.” That project is currently being studied by San Francisco planners.
Just days after an infantile gag to change its HQ sign, it was revealed that Twitter ceased to exist as a legal entity after being gobbled up by Musk's X Corp
Even with Golden State on the road, the Warriors' home turf remains a prime postseason party spot for members of Dub Nation
Both plans also appear to show BART trains traveling along the I-980 corridor in Oakland. That freeway, which separates West Oakland from downtown, has long been eyed by activists as a potential target for removal, à la the Embarcadero Freeway in San Francisco.
New BART stations could appear in Alameda, Jack London Square, downtown Oakland and East Oakland near the San Antonio neighborhood. Jack London Square, where the A’s are hoping to build a massive development anchored by a new ballpark, and West Oakland could become major transit hubs, hosting both BART stations and regional rail stations.
While much of the new construction envisioned by Link21 would happen in Oakland and San Francisco, planners are eager to highlight the project’s regional benefits. Its name is a reference to the 21 counties in the Northern California “megaregion,” stretching from the Sierra foothills to Monterey Bay.
In tandem with several other planned or under-construction rail projects, like San Francisco’s Downtown Extension, Link21 would enable a host of new transportation connections throughout the region. Travelers from the foothills, the Sacramento area and the Northern San Joaquin Valley would have easy access to San Francisco and the Peninsula. Train travel from Monterey and Santa Cruz to Oakland and San Francisco could become a reality.
Link21 remains a long way from reality. Project planning and approvals are expected to last through 2027. Completion is roughly projected for 2039. The very early cost estimate for the project is about $29 billion in year-of-completion dollars.
One potential funding source could be “value capture” — generating funds through increases in property values surrounding the new stations created by the project. Link21 recently published a paper identifying several potential value capture mechanisms that could generate billions of dollars for the project.
Besides cost, another hurdle for the project could be the Bay Area’s fragmented array of transit agencies. While BART and Capitol Corridor are planning Link21, the project will likely require close collaboration with Caltrain, California High-Speed Rail, San Francisco Municipal Transit Agency and other transit providers and governments.
Members of the public hoping to learn more about Link21 can participate in a series of upcoming webinars tailored to specific geographical areas. The first, on Oct. 18, will focus on the entire megaregion. The Oct. 20 meeting will focus on San Francisco, and the Oct. 26 meeting will focus on the East Bay. All of the meetings will be accessible via Link21’s website and will last from 5:30 to 7:30 p.m..
