San Francisco has an unrecognized opportunity to cost‐​effectively shelter thousands of its homeless residents. The city’s massive Salesforce Transit Center has two unused subterranean levels that could provide over 400,000 square feet of shelter space. Assuming 100 square feet of space per occupant (well above state building code requirements), this facility should be able to accommodate 4,000 individuals. Since the city’s most recent point‐​in‐​time count identified 4,397 unsheltered homeless people, utilizing this space for shelter would make a tremendous difference.

When the transit center was built in the 2010s, the two lower levels were included to accommodate future commuter and intercity train service. But before this space can be used as a train station, a rail extension must be completed linking the facility to the present Caltrain terminal 1.3 miles away.

Trains will not be arriving at the Salesforce Transit Center any time soon. According to the Federal Transit Administration, a grant agreement is expected to be completed in 2025 and service would begin in 2031. And, given the delays that have plagued recent Bay Area transportation projects, 2031 seems highly optimistic.

As far as I can tell, the idea of using the underground space at the Transit Center as a shelter has not been considered. Until recently, city policymakers have been focused on creating permanent supportive housing for the homeless rather than shelters. But given the high cost of building permanent housing in San Francisco, the city’s weaker budget output and increased public pressure to clear street encampments, policymakers now seem more open to quicker, less costly options.

A recent city‐​mandated report from the San Francisco Department of Homelessness and Supportive Housing proposed adding 2250 shelter slots over three years. The report does not specify where the beds would be located, but does quote a start‐​up cost of $57.8 million, which works out to just under $25,700 per bed. Annual operating costs are estimated to range from $58,400 to $70,800.

County Supervisor Raphael Mandelman told the San Francisco Chronicle, “It seems like we should be able to do this for far cheaper. It’s hard to understand what’s driving the cost. I think we are not looking at the most cost‐​efficient models.” Perhaps leveraging an unused public facility is the more cost‐​efficient model San Francisco needs.