SAN FRANCISCO (KGO) -- While no one knows for sure when the next big earthquake might hit, San Francisco says it's getting ready.
On Wednesday, the city's building inspection commission passed a new piece of legislation requiring owners of concrete buildings to hire an engineer to complete a seismic safety screening.
Supervisor Myrna Melgar authored the bill.
"We know that there are potentially hundreds of buildings. We don't know how many of them are built up to code or not," Melgar said.
The screenings would impact owners of two types of buildings, which could need retrofit upgrades to become earthquake safe.
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The first are known as tilt-ups and include things like warehouses and grocery stores.
The second type are so-called non-ductile concrete buildings.
"These are older, concrete buildings that get their strength from concrete, that in some cases may lack the steel reinforcement to resist a really large earthquake," said Laurel Mathews, senior earthquake resilience analyst with the city.
"While the legislation would require building owners to do the seismic screenings if it becomes law, as of now there is no requirement for them to then do retrofittings if it was deemed necessary.
Whether or not that changes in the future though, is something the supervisor wouldn't comment on.
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"I'm not ready to say that today, because we really don't have a list. We don't know if we're talking about high hundreds or ten. We just don't know. And that has to be weighed against the costs," Melgar said.
City officials estimate the cost to do the screening can range anywhere from a few hundred to a few thousand dollars.
A cost Supervisor Melgar says is worth it, especially when considering the possible life-saving implications.
"We live on the San Andreas Fault. It is unstable ground. This is a very small cost compared to the cost of insurance, the costs of things when things go wrong, what could happen," said Melgar.
The legislation still has to make its way through another committee and then be passed by the full Board of Supervisors in May in order to become law.