Maps for Proposed San Francisco Bay Tunnel Revealed

Planners presented two options for new tunnels that would help connect more parts of the Northern California megaregion to San Francisco and Oakland.

1 minute read

September 23, 2022, 8:30 AM PDT

By Diana Ionescu @aworkoffiction


Plans for a new tunnel across the San Francisco Bay are shaping up as the public finally got a look at “the most detailed maps yet” showing the proposed tunnel’s route. As Benjamin Schneider reports for the San Francisco Examiner, planners for the Link21 project revealed two options for the tunnel. “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.”

The second option would have two tunnels separating BART and regional trains. “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.’”

Across the bay in Oakland, “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.”

Link21 is named for the 21 counties that could be served by new connections enabled by the project.

Schneider notes that “Link21 remains a long way from reality. Project planning and approvals are expected to last through 2027. Completion is roughly projected for 2039.”

Wednesday, September 21, 2022 in San Francisco Examiner

Young Professional

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban and Environmental Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban and Environmental Planner

Get top-rated, practical training for planners

"Planetizen federal action tracker" logo superimposed over black and white image of US Capitol dome.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

October 28, 2026 - Zachary Whalen

A car drives through a puddle, making a large splash. Rain pours down.

California plans to bury El Niño’s downpour

If the state plays its cards right, it may be able to store a billion acre-feet of El Niño’s water in aquifers.

October 28, 2026 - Grist

A pencil rendering of Foundry Park, which shows skyscrapers and public green spaces.

Chicago breaks ground on $3 billion megadevelopment

The new neighborhood, titled Foundry Park, will one day host 3,700 residences.

October 23, 2026 - Chicago Sun Times

A rendering of a high speed rain station in California, with wide platforms and a sleep train with yellow highlights.

California High-Speed Rail Authority CEO resigns after $600,000 scandal

Under Ian Choudri, the authority used taxpayer dollars to fund first class flights and trips to nightclubs.

October 30 - Cal Matters

 A bridge stretches across the Missouri River at Chamberlain, South Dakota.

Want to study the Missouri River? Soon, you may need unanimous approval from 10 states

Legislation would require 10 governors’ permission to study or build projects moving water outside the basin.

October 30 - South Dakota Searchlight

Lake Powell with much of the water evaporated.

Desperate measures: Advocates weigh draining Lake Powell to fill Colorado River

Draining the reservoir could reduce evaporation losses by a couple hundred thousand acre-feet.

October 30 - Yale Environment 360