Prologis, Caltrain Eye 850-Foot Tower in SF’s Mission Bay

Prologis and Caltrain envision an 850-foot mixed-use tower in San Francisco’s Mission Bay and China Basin.

The locally based commercial developer and the local commuter railroad line have floated a plan to build the second-tallest skyscraper in the city on 20 acres of railyards along San Francisco’s Townsend Street, the San Francisco Business Times reported.

The joint venture unveiled the concept to build the tower at 4th and King Street Station at 700 Fourth Street in a virtual community meeting last month. No project application has been filed.

“We think this is the second-most important transit hub in the city, so it should be the second-tallest tower,” Kristen Hall, whose eponymous design firm is working on the site’s redevelopment, told attendees.

Prologis owns the property. Caltrain has permission to operate its rail lines there. In 2021, both began to explore a feasible development at the site.

The 850-foot tower would be the tallest building at the railyard redevelopment, within a broader project plan, which the city expects Prologis and Caltrain to file this spring.

Prologis and Caltrain envision a transit village with a mix of homes, offices, shops, restaurants and open space.

The railyard project would also make streetscape improvements to help link Mission Bay, Showplace Square and South of Market, neighborhoods historically separated by the yards.

The number of homes and amount of commercial space under consideration were not disclosed.

Both the San Francisco Office of Economic and Workforce Development and the Planning Department expressed support for significant height and density at the railyards site, Tuesday, though it is not clear whether the city will support the 850-foot building.

If all goes as planned, Prologis and Caltrain could secure project approvals in 2027, and begin early construction work in 2028, according to a timeline released by the Planning Department and seen by the Business Journal.

The 4th and King Street Station is part of a railway redevelopment project that includes the Portal, a 1.3-mile rail extension that will connect Caltrain and eventual high-speed rail from 4th and King into the Salesforce Transit Center, according to the Business Journal.

The completion of the Portal will allow Prologis and Caltrain to move forward with the railyards’ redevelopment, either by moving Caltrain’s rail lines underground or by reworking the footprint there.

A plan for a new transit neighborhood in Mission Bay comes on the heels of San Francisco building 1,205 homes last year as of early December, fewer than any year since the Great Recession.

— Dana Bartholomew