Cities across California are struggling with how to convince property owners to retrofit buildings at risk of collapse during a major earthquake.
San Francisco this week is using an unusual tactic: trying to publicly shame building owners into shoring up their structures to better withstand shaking.
The city will slap large signs — in multiple languages, with red letters and a drawing of a destroyed building — on hundreds of apartment complexes that violate San Francisco's seismic safety laws.
No California city has gone so far to inform the public about potentially dangerous buildings and pressure property owners to make fixes.
Los Angeles is considering a similar approach. Mayor Eric Garcetti has proposed what would be the nation's first letter grading system to alert the public about the seismic safety of buildings. He has also said he wants to require owners to retrofit buildings that are at risk but is still working out the details of his plan.
The San Francisco notices, written in English, Spanish and Chinese, will go on buildings whose owners have not complied with a landmark city ordinance passed last year. The law requires that wood-frame apartment buildings and hotels be evaluated. The city estimates that up to 4,000 will need to be retrofitted under the law.
"We wanted something that caught people's attention, which I think this very well does," said Patrick Otellini, San Francisco's director of earthquake safety. "We saw that other programs had been wildly unsuccessful. We wanted a poster that drives change and lets people know what's going on."
Some property owners as well as tenants don't like the idea of warning signs.
"You're putting people in panic mode. That would be a horrible thing to put in a window. All you see is the words 'earthquake warning,' " said Huy Le, who owns a salon in the Castro District and leases space underneath a hotel. "It's almost as good as saying, 'Don't come into this building because it's going to collapse.' "
Others supported the signs, saying that the public has a right to know the structural soundness of the buildings where they live and work.
"I want to be safe," said Katie Stephens, who rents a Marina District apartment. "That's part of the responsibility of being a landlord in San Francisco. It may cost a lot, but what's most important is that his tenants are safe."
This has been tried before, in Berkeley. In 2005, the city began placing smaller warning signs on at-risk wooden apartment buildings and required owners to send letters to tenants warning that their home could pose "a severe threat to life safety." City officials said that after the notifications, more than 100 buildings were retrofitted voluntarily. The city passed a mandatory law last year to get the 139 remaining buildings retrofitted.
San Francisco's law covers many more buildings and is likely to attract more attention.
The law targets wood-frame apartments and hotels with weak first stories. Often, these first floors house garages, carports or storefronts with limited structural supports holding up the rest of the building. During a big earthquake, the upper floors can cave in on the first story.
Building owners had until Monday to fill out seismic retrofit screening forms, which will determine whether their properties will need to be evaluated and ultimately retrofitted. The signs will be placed on the buildings of owners who failed to complete the forms.
City officials sent letters to owners of about 6,600 buildings a year ago asking them to fill out this initial form. About 90% have responded. But the city has not received forms from the owners of roughly 650 buildings as of Monday evening. In addition to the signs, these owners also face fines.
The vulnerability of wooden apartments is well known. A couple and a baby died after an apartment building in San Francisco's Marina District collapsed during the 1989 Loma Prieta earthquake. At a complex in Northridge in the 1994 quake, 16 people died when the upper floors caved into the ground story, which had carports and apartments. Many suffocated under the debris.
Retrofitting these types of buildings is expected to cost $60,000 to $130,000, typically by adding steel supports or new walls to the ground floor. City officials have offered to connect owners with banks offering low-interest loans for retrofits.
Most cities in California do not require wood-frame apartment buildings to display a public warning or be retrofitted. Only a few cities, including Santa Monica, Berkeley and San Francisco, have mandatory retrofitting laws on the books.
However, the state has a 23-year-old law requiring owners of old brick structures to post earthquake warning signs identifying them as unreinforced masonry buildings that "may be unsafe in the event of a major earthquake."
Many cities don't enforce that state law, the California Seismic Safety Commission found. The commission said in a 2004 report that only 276 unreinforced brick buildings out of roughly 22,000 statewide had posted placards, according to its survey of local governments.
One of those with no warning sign was a historic brick building in Paso Robles, which collapsed in the 2003 San Simeon earthquake, killing two clothing store workers.
After that, the neighboring city of San Luis Obispo sped up mandatory retrofits of brick buildings.
Now, only 14 of that city's 126 older brick buildings have not been retrofitted; all must be strengthened by 2015.
"Acknowledging the risk is the first step, but it's not the last step," said San Luis Obispo's community development director Derek Johnson.
The signs helped: "More than anything, it creates a real public awareness about the issue…. The public has the right to know."