Ongoing San Francisco campaign promotes enhanced building safety to prepare city for next big earthquake

SAN FRANCISCO (KGO) — As we approach the 36th anniversary of the devastating 6.9-magnitude Loma Prieta earthquake, you may be wondering, how safe is San Francisco? The city has an ongoing campaign to enhance safety if we’re ever to face another big quake again.

Come December, owners of thousands of presumed concrete buildings in San Francisco will be asked to take part in a screening program. In the meantime, soft-story building owners have been overwhelmingly compliant in making sure their structures are safe.

The devastation of the 1989 Loma Prieta earthquake is not long forgotten.

“In a lot of ways, the Loma Prieta earthquake woke us up to our seismic risk,” said Laurel Mathews, earthquake program manager for San Francisco’s Office of Resilience and Capital Planning.

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Around 2013, Mathews says San Francisco instituted a mandatory retrofit program for wood framed soft-story buildings that were three or more stories with five or more units.

A soft story building is a building where, on the ground floor, there’s more open space than there is above the ground floor.

In San Francisco, Mathews says that usually means on the ground floor, there’s a parking garage or business. And above the ground floor, there’s apartments. These types of buildings were in danger of damage or collapse.

The program has been hugely successful.

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“About 40,000 housing units are now in safer buildings because of this program. The program is currently at 95% compliance,” Mathews said.

The remaining 5% have engaged with the Department of Building Inspection in some way.

Beginning in December, the city will begin focusing on concrete buildings built before around the year 2000.

“Some of the concrete buildings built before that date can be a bit brittle and don’t have enough steel reinforcement to resist the sideways forces of a really big earthquake,” Mathews said.

There’s currently no mandatory retrofit program for concrete buildings. Rather, the city has developed a screening program for these types of buildings.

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“Building owners will have until June of 2027 to submit building information to the Department of Building Inspection,” Mathews said.

The screening will also look at a type of building called “tilt-ups,” which are one-story commercial and warehouse type buildings. With the information, Mathews said the city hopes to have a better idea of next steps and whether a mandatory retrofit program similar to the soft story one would be the right approach.

Mathews estimates that approximately 4,000 building owners of concrete and/or tilt-ups will be asked to participate in the screening program. She says soft-story buildings were addressed first, because they were seen as low hanging fruit. Tenants didn’t have to move out and the cost for retrofitting was relatively low compared to the buildings’ value.