San Francisco, a city that knows its faults

Low vacancy, so many homeless people, beautiful old buildings, shuttle busses to silicon valley… and warning, I’m going to talk about earthquakes. If it gets scary, stick with me: there’s good news at the end, ways to better understand the specific risks facing San Francisco, and some easy places to start.

Let’s Talk Numbers
After the 1989 Loma Prieta earthquake, 11,500 Bay Area housing units were uninhabitable. If there was an earthquake today, the current estimate (from Spur) is that 25% of SF’s population would be displaced for anywhere between a few days to a few years. However, San Francisco’s top shelter capacity can only serve roughly 7.5% of the overall population. And that is only for short term stays in places like Moscone center. So where would the remaining 17.5% of the population go?

1. Some people may decide to leave the city and start over somewhere else (something called “outmigration”, which is not ideal for the economic health of a city).

2. And some people take longer term housing in vacant units around the city. But this is particularly tough in SF because vacancy is currently at an all time low of about 4.2% vacant units.

3. This brings us to the most ideal scenario: staying put. Something referred to in the emergency management world as “shelter-in-place.”



What is Shelter-in-Place?
Shelter-in-place is “a resident’s ability to remain in his or her home while it is being repaired after an earthquake — not just for hours or days after an event, but for the months it may take to get back to normal. For a building to have shelter-in-place capacity, it must be strong enough to withstand a major earthquake without substantial structural damage. […] residents who are sheltering in place will need to be within walking distance of a neighborhood center that can help meet basic needs not available within their homes.”

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