San Francisco Is Ready to Explore a Geary Subway. It Would Be a Massive Undertaking

For almost a century, San Francisco city leaders and transit visionaries have imagined a subway along the Geary Boulevard corridor.

Those ideas, which began in the 1930s with a relatively modest proposal to put Muni streetcars underground along Geary’s crowded downtown section and in the 1950s envisioned the route as a key piece of a BART line to Marin County, have never gotten past the early planning stage.

But now, as part of an effort to prepare for the city’s future transit needs, the San Francisco County Transportation Authority is exploring a new version of this old idea.

At virtual town hall meetings Wednesday night and Saturday, the agency will outline proposals for a subway that would stretch more than eight miles from downtown along Geary to 19th Avenue, then south to Daly City.

If it became a reality, it would be the biggest subway project in San Francisco’s history. And it would not happen overnight: Developing the plan and building it could take 15 years or more and cost at least $15 billion, according to the SFCTA.

The Geary/19th Avenue corridor was designated for study under ConnectSF, a long-term initiative to invest in the city’s transit network, including by expanding and modernizing its rail system.

Geary has long been the main east-west route between downtown and neighborhoods west of Van Ness Avenue, and 19th Avenue is a key connector for the Richmond and Sunset districts and San Francisco State University. A subway along the thoroughfares — two of the city’s busiest — could carry as many as 300,000 passengers a day.

The line would serve a part of the city that is expected to see a dramatic increase in housing construction in the coming decades. Just on Tuesday, the Board of Supervisors unanimously approved a plan to develop the parking lots around the Stonestown mall into nearly 3,500 new homes, according to Mayor London Breed’s office.

The subway would also provide a fast new connection to the city’s existing rail network and future regional rail connections — a second transbay tube, for instance.

The SFCTA’s virtual town halls will include Spanish and Chinese language interpretation and take place on Zoom at 7 p.m. Thursday and 10 a.m. Saturday. Participants can sign up for either session here.