They should have been built like the skyscrapers in Tokyo. They swayed back and forth a lot during the last large earthquake that hit nearby.
I wouldn't go into one of those S.F. ones for a million dollars if a big quake could be predicted. The subsoil supporting them is too poor. Who can be sure the tallest ones couldn't collapse or tip over during a big quake which could last for minutes? It is crazy not to build any multi story buildings to withstand the largest possible quake that might hit. Those skyscrapers will still be there when the next huge quake hits.
3
People living in San Francisco (like myself) thinking this article is to scare or criticize us! WAKE UP! Buildings on the small patches of Bedrock are not immune to earthquakes! And this does not include the land fill that many of the buildings are resting on. San Francisco was essentially a BEACH when it was discovered in 1769! Case and point- The Millennium Tower. The darn building is sinking and the city government don't know what to do! A Japan company has a theory on how fix it.. at a cost of $4 billion. California building code... and SF is knowingly breaking them and putting the people at risk. All in the name of profit and dividends. Enough with building more! The last thing SF needs is more people. The current infrastructure can not support it. When THE big one does hit and buildings fall and the land fill ground sinks, there will be a lot of finger pointing! Get your head out of the "clouds" and realize that this has to be taken seriously.
7
Why no mention of 181 Fremont? Foundation down to bedrock. REDi Gold rated; immediately re-occupancy after a major seismic event. Structure Magazine June 2016: " 181 Fremont Tower, located in downtown San Francisco adjacent to the new Transbay Transit Center, will arguably be the most resilient tall building on the West Coast of the United States when completed in 2017. At that time, it will be the second tallest building in San Francisco (802 feet). The tower was designed to exceed CBC-mandated (California Building Code) earthquake performance objectives for new tall buildings by following a “resilience-based-design” approach. It was designed to achieve immediate re-occupancy and limited disruption to functionality after a 475-year earthquake (i.e. functionality is reestablished once utilities are restored) by targeting specific design criteria to achieve a “Gold” rating as outlined in the REDi Rating System (REDi, 2013). To achieve a “Gold” rating required that the structure is designed to remain essentially elastic (under 475-year shaking, which is approximately the recurrence interval for the CBC design basis earthquake, or DBE) and that the non-structural components are designed for more stringent force and displacement requirements relative to the code. The owners, Jay Paul Company, were also provided with additional recommendations for implementation of preparedness measures that would aid in achieving the enhanced performance objectives."
6
There are 2 issues with this article.
1) It is the type of story many people want to write, especially east coast media. There has been a visceral want-to see-SF fail trend for several years. I have lived in 2 cities for many years ,SF and NYC, and its easy to see this bias in media, venture capital, investment banks. So much capital and wealth has shifted to SF and the Valley that a level of resentment in city-of-money NYC is inevitable because that how you measure.
2) As to the substance, SF code has over the past 2 decade striven to find a reasonable,conservative point where likely technical performance in EQ balance with costs and "aesthetics" of building. It not unlike the question of how do make a new WTC completely impermeable to terrorism. You can get close to 100% structural survival -- close-- but to raise the level from the 90% likelihood of requires an exponential increase in cost and also a severe impact of the appearance of structure-as-prison that many find unacceptable.
how many people want to live like that?
3) Message to NYC -- why don't you figure out how to fix your miserable subways system, when it soon collapses the impact on the NYC economy will be profound and long lasting, and an embarrassment from which you will never recover.
12
After the 6.9 mag quake in 1989 I can only remember one building that collapsed (in on itself). A 10 or 12 story wood frame building near Embarcadero Center built post 1906. As a whole the financial district buildings escaped major damage. Not mentioned is that the Millennium Tower's pilings are not built down to bedrock as opposed to it's across the street neighbor the much higher Salesforce Tower. The 1906 quake did damage most buildings but the tallest at the time survived the quake, whose 7.9 mag epicenter was just 3 miles off the coast from Ocean Beach. Having said all this though the Financial District is the last place I'd want to be in a large quake.
4
We are still trying to get skyscraper builders to install sprinkler-systems in case of fire and they balk at spending the money. I doubt any buildings are much better quake wise if a dollar can be saved somewhere.
1
I wonder why there seems to be so much concern-trolling by east coast journalists over housing policies and building codes in San Francisco and LA lately, like it matters to them or something. Are there a special investigative units devoted to predicting doom and finding fault with the Golden State, or what? Next you'll be telling us that our pizza is unacceptable.
8
So what exactly is the point of this article but to try and scare us? I am so tired of being made to feel terrified by elements beyond my control. The earth is going to open up and swallow you; the President is unhinged and may stumble into a nuclear conflict; climate change will eventually kill us all. Now go about your daily routine. How is a person supposed to take such threats seriously and still life free of paralyzing fear?
4
I wonder how California's codes compare to those in Chile. Chile regularly has strong earthquakes, and relatively little destruction. What would it take to bring California's codes up to par? It is shocking that SF is allowing -- even encouraging -- the construction of high-rise buildings on unstable ground. And even more shocking that they allow this type of development in the face of inadequate engineering specifications.
2
There was no mention of the "bedrock' areas. A friend of mine owns a building on bedrock in the downtown area - close to the entrance to the Bay Bridge. He has been solicited night and day from buyers to purchase his building and the property which is estimated to be worth more than a billion dollars.
There is bedrock throughout SF. Properties on bedrock won't be damaged as those on land and landfill. The quake's effects brought to light SF City/County's contingency planning for another like event. In their calculus for damages to people and proper, they had an estimate (the population of SF was considerably less in 1989, 1990) for the number of deaths they were definitely going to deal with. So, residents like I were grossly aware of facts that the SF City/County plans but cannot protect individuals during that earthquake from injury. They plan on that. In all probability, SF City and SF COUNTY (the same!) has a higher number for the deaths they expect and cannot stop from happening.
Reading the article, there was no mention of the "bedrock' areas.
A friend of mine owns a building on bedrock in the downtown area - close to the entrance to the Bay Bridge. Buyers solicit him daily asking him to sell his building and property which is estimated to be worth more than a billion dollars.
There is bedrock throughout SF. Properties on bedrock won't be damaged as those on land and landfill.
HIgh5. And any building over 50 feet (?) should be grounded to bedrock. How the building department signed off on these towers built on 'tables.' I'd love to see the seismic shake simulations for Millennium. Will the table act as an anchor and the building will sway until it falls over? The latest proposal to sink hundreds of Micro piers to bedrock shows how big the gap is to a valid design.
USGS: 99% change of a 6.7 earthquake in the next 30 years. What will survive? Perhaps it's better to compare SF and Mexico City, or Kobe, so we can benchmark and learn from others.
https://pubs.usgs.gov/fs/2008/3027/fs2008-3027.pdf
"Ron Klemencic, the chief executive of Magnusson Klemencic Associates, the company that did the structural engineering for Salesforce Tower, says he agrees that water and sewage systems need higher strength requirements, but not high rises. “Buildings falling on top of other buildings — that’s not going to happen,” Mr. Klemencic said."
Who thinks this guy sounds like the architect in the "San Andreas" movie? And we all know how he ended up, right? (admit it, you watched the movie - c'mon....)
4
how about the engineers that designed the "unsinkable" Titanic?
3
“We saw that as a symbol of the new San Francisco and we wanted the building to be at least 1,000 feet in height,” said Dean Macris"
A symbol of San Francisco. A big commercial structure with a very romantic name. Not. What about the Golden Gate Bridge? The Bay? Coit Tower? Cable cars? Using some speculator's private investment as a civic symbol for a city that is beautiful, historic, and considered one of the finest urban areas in the world is crass . The rest is just ego.
So much for the humility that professor Kanamori advises.
11
“Manhattanization” was a dirty word when NYC was broke and in the pits, crime was nearly out of control, business and residents were fleeing to the suburbs. Now the city has reinvented itself and has a luster and dynamic flair from a rebooted economy on par with London, Tokyo, Paris and others. As the study of any of these magnificent cities will show they cycle through harsh periods of economic and physical disasters.
That said, the siting of SF alone is breathtakingly beautiful and will always inspire.
3
How old are you may I ask? The City reinvented itself? Really.
You must work for Facebook at its Menlo Park location and its leader Mr. Smart Face. Stop drinking the cool aid.
San Francisco has been destroyed by the dot com GIVE ME EVERTHING. I disserve it.
Read Mr. Steve Wozniaks' opinion of the destruction Mr. Zuckerberg has inflicted upon the City of Menlo Park and SF.
5
I've lived in SF (somehow) for 49 years. San Francisco has reinvented itself several times since I moved here in 1969. And quite a few times going back nearly 200 years. The group I came to SF with in the late 60's changed SF politics within 10 years from a Republican mayor and many Republicans on the Board of Supervisors to Democratic mayors and Board members, many of them female and gay. The old folks at the time accused us of ruining SF. A lot of iconic SF was disappearing even then especially downtown when the high rise boom started. Read Gary Kamiya's book Cool Gray City of Love on the history of SF - probably the 3 biggest reinventions have been the gold rush, the local war industries during WW2 and now the dot.com boom. It is the nature of cities to change and grow. If you don't like that then you live elsewhere.
4
Hello NYT. Clearly, you haven't done your homework. All those tall buildings downtown are built on 6 inches of sand, which is on top of hundreds of feet of solid bedrock! Check with the USGS for the official tally. Would not have been possible to build two suspension bridges without solid bedrock. Ditto for buildings. The stuff that liquifies are old garbage dumps close to the Bay. People began building on those sites at the end of 19C because it appeared "solid". Mission Bay is built on enormous concrete "pillars", just like Venice is built on a native wood (whose name escapes me at the moment), that resists water rot. Remember that the 1906 earthquake razed the City by fire, not by earthquake.
6
The article is written by someone who has NOT investigated the land maps of SF and SF County. You can get a digital map of the entire bedrock areas in SF easily.
6
It'd be a shame, SF is a pretty city.
2
One of the features of land that "liquifies" is that its water content can be high. Think of mud being agitated, for example by sonication.
One way to reduce the chance of liquefaction is to sink tubes with apertures located periodically in their sides vertically into the ground, and pumping out the ground water that collects within the tubes. Dry soil has much less proclivity for the particles to move past each other than do the particles in wet soil.
The problem presented by liquefaction is that the "liquified" ground behaves like jello, and does not support the shear or tilt forces that the vibrations of the earthquake exert on buildings and other structures.
I have no way to calculate how deep such tubulation would have to be to prevent liquefaction, but my sense is the deeper the better. All the way down to bedrock would make sense. Looking at the maps given in the article, some of the areas that appear to be most prone to such liquefaction are situated close to water, and consist of fill or other loose soil. That soil probably has significant water content.
A similar problem to that in San Francisco is present in the Back Bay section of Boston, which is definitely constructed on fill. Look up the historical record. The three most earthquake prone areas in the US are, in order, the West Coast, the area in the vicinity of St. Louis, MO, and New England.
2
In 2006, AB 1978 required that "Hospitals are required, under the Alfred E. Alquist Hospital Facilities Seismic Safety Act of 1983 (Chapter 1 (commencing with Section 129675) of Part 7), to improve, or remove from acute care service, buildings that pose a significant safety risk of collapse and danger to the public by January 1, 2015."
further "Hospitals are also required by that act to repair, rebuild, or remove from service, buildings that may not be repairable or functional following strong ground motion, by January 1, 2030."
Why are sky-scrapers not held to the same standards when they are concentrated in city centers and where the risk of life is so great? To impose any code on 160 buildings after the fact will not gain any traction and instead will be resisted at all costs because of the massive expense involved.
I think the movie San Andreas nailed it.
4
After Fukushima, I met a couple of my colleagues (computer science professors) who said (jokingly) they should have been seismologists, saying "You can be instantly famous once a big earthquake comes, even if you have few papers."
3
My father who was a VP at a stock brokerage firm which had analysts who made predications, informed me in the early 1970s that Japans installation and operation of multiple nuclear power plants could lead to the death of the Earth. He was also a geologist with the USGS in the Fifties. Everyone including the Japanese knew full well how dangerous those power plants were because they were construction RIGHT ON A FAULT LINE.
1
“Ten percent of buildings will collapse,” said Lucy Jones, the former leader of natural hazards research at the United States Geological Survey who is leading a campaign to make building codes in California stronger. “I don’t understand why that’s acceptable.”
But I think the math is wrong. Design specs say buildings have to have a 90% chance that it will not collapse, which 10% that a particular building will collapse. The building next to it has its own 10% chance of collapse that has nothing to do with whether the first building collapses and so on. So it could be 10% of all buildings collapsing or it could be 23.5% that fail, or none, or all of them.
2
No, the math is right (at least taken at face value); the claim follows from the law of large numbers. If each of *many* buildings independently has a 10% probability of collapse, then overall you expect nearly 10% of them to collapse. If you only have two or three buildings, each with a 10% probability of collapse, then you are right; it wouldn't be that surprising if none, or 20% of those few collapsed. But as you increase the number of buildings, the fraction of the total that you expect to collapse gets closer and closer to 10%. With ~100 buildings, it would be quite surprising for none of them to collapse (and even more surprising for all of them to collapse). With ~1000 buildings, it would be truly miraculous for none to collapse (and even more miraculous for all to collapse). It's not clear from the article how many buildings are subject to the 90% requirement.
There are *many* caveats, however. The 90% survival requirement must be for quakes of a particular strength and type. Obviously, a stronger quake would take out more; a weaker one, fewer. Also, hopefully many buildings are built to *surpass* rather than merely meet the 90% requirement. Finally, it's probably not the case that failure will be independent. Esp. for tall buildings, failure of one will likely affect neighboring buildings.
2
Adding on to this topic, I wonder if the 10% chance of collapse factors in the effect of other nearby skyscrapers collapsing. I am not an engineer, so I have no idea if this is true or not, but it seems like having one skyscraper collapse would increase the chance of other neighboring skyscrapers sustaining damage as well, particularly if the building tilts and falls sideways.
Question for any engineers: could an earthquake trigger a domino type situation with one toppling skyscraper knocking into others?
1
High rise is not the problem, Tokyo has more high rise towers than San Francisco. Seismic design is the key, the bay area should implement the highest earthquake engineering standard in the major building codes.
2
I wonder what California can learn from that most earthquake-prone nation--Japan. I'm still mesmerized by amateur videos showing how the very high skyscrapers of central Tokyo swayed ominously during the immense 9.0 monster earthquake that struck a little more than 200 miles northeast of that city in 2011. There was some structural damage to these behemoths, but none toppled. And it seemed like everyone in those skyscrapers emerged unscathed.
More importantly, a huge number of those very high Tokyo skyscrapers struck by the 2011 earthquake were built on landfill next to Tokyo Bay. The underlying geology of the soils there is very similar to what we see in central San Francisco--reclaimed land that easily liquifies during strong shaking. Yet those structures didn't topple either.
What has been the experience of the engineers in Tokyo? What's their engineering and skyscraper codes like? The fact that this article didn't attempt to ask these questions, or to tie back to Tokyo's 2011 experience, leaves a huge explanatory hole that could've been better explored with regards to this very important topic.
7
@Lubo-
Tokyo was leveled by the Great Kanto Earthquake of 1923 (estimated strength, 7.9, the epicenter 80 miles southwest). An estimated 150,000 people died.
1
Tokyo suffered the same fate as SF in 1906. Both cities were swept by fire right after the quakes.
Great photos and graphics. I will keep my nytimes subscription going.
4
Guess what? Buildings in San Francisco are actually designed for seismic activity.
City-shattering earthquakes are theoretically possible anywhere, and the same statistics that are used to set the design earthquake loads in San Francisco may have been used to justify completely ignoring the possibility of an earthquake in your own city.
Have a nice day! ;)
1
Irresponsible. And I LIVE here!
1
Supreme folly.
Supreme greed-driven folly.
4
Everyone thinks of Skyscraper Buildings as being tall and slender (and rooted deep into bedrock). In a liquefaction zone - a building with a wider base is more likely not to tip into its neighbors. Would it be possible to design "flying buttresses" to inter-connect the downtown tall buildings to form a singular large base structure. I think the term "Archeology", might apply here. In this design, every building would help to support every other building minimizing a domino effect when (not if) the next large earthquake happens.
Overturning effects (think toppling) would probably be mitigated, but I don't think that base shear or other considerations for seismic design would really be affected. Some things would possibly be worse. In fact, you end up with one big, super-complex city system that has to be treated as a single entity for structural engineering purposes, instead of a series of individual modules that are *mostly* independent of each other.
If there would actually be a net benefit to such a thing, the legal hurdles of getting building owners to cooperate enough to make this happen are probably enormous. It's probably something that could only ever happen if the city eliminated private building ownership and had complete control over development. Interesting idea, though.
I am fairly certain that skyscrapers do not behave like dominoes when one falls into another. That's only in movies and video games.
true. I thought for sure the twin towers would topple over. They imploded.
2
Like everything else (e.g., education, healthcare) we know we need it but no one wants to pay for it. Then eventually we pay "in spades."
2
"For years the city restricted building height to 500 feet in most neighborhoods."
I think you mean 50 feet...if height were "restricted" to 500 feet, San Francisco wouldn't have the housing crisis it does.
7
Those buildings have nothing to do with the housing shortage... Purely tech.
4
Yeh. But SF is NOT a good place to live. The Red Cross and FEMA were here in Sacramento a lot to navigate to Santa Rosa after the fires. A FEMA disaster agent told me that both agencies are planning for a Calfiornia earthquake and injuries to people NOW. They expect to have it happen very soon.
2
https://oceanservice.noaa.gov/facts/tectonics.html
Tectonic shift is the movement of the plates that make up Earth’s crust.
Some regions, such as coastal California, move quite fast in geological terms — almost two inches a year — relative to the more stable interior of the continental United States. At the “seams” where tectonic plates come in contact, the crustal rocks may grind violently against each other, causing earthquakes and volcano eruptions. The relatively fast movement of the tectonic plates under California explains the frequent earthquakes that occur there.
Question: What do geologists say after they detect that an earthquake has occurred?
Answer : Shift happens.
5
San Francisco’s architects and civil engineers involved in erecting a multitude of skyscrapers with little regard for their seismic vulnerability should take a good look at the Chilean building code, which has allowed skyscrapers to survive the 2010 earthquake with a magnitude of 8.8 and duration of 3 minutes. The Gran Torre Santiago, a 64-story skyscraper, or the neighboring Titanium La Portada skyscraper suffered no significant damage during this very strong earthquake. Recently built tall buildings in Santiago swayed with the shocks of the quake, but suffered only cosmetic damage. The quake did cause damage to Santiago's airport and about 300 deaths, but it could have been worse. Why should San Francisco’s building code be less stringent than that of Chile's?
3
Ah, but what lies beneath Santiago, Chile, is probably not the same.
What lies beneath San Francisco? Much of the eastern shoreline from AT&T Park south to San Jose is actually estuary land reclaimed from San Francisco Bay; “fill”, and enormous tidal mudflats. The Marina and Sunset Districts were built on sand dunes. Two centuries ago Market Street from Montgomery west to the Ferry Building was underwater, the area slated for highrise overbuilding.
Very tall buildings can rest on thick teflon rocker pads designed to slide and sway. But I don’t know how you can design around deep buried mud and sand berms prone to liquify during any seismic disturbance. Outright collapse might be prevented by clever engineering. But that cleverness might not extend to prevent those structures’ centers of gravity from shifting beyond recovery.
2
Much of the coastal Marina District was filled in with rubble from the 1906 quake, especially the area where the Panama Pacific Exhibition was held. Before that it was bay and marshes. During the 1989 quake many of the houses sank several inches along Marina Blvd and the greatest concentration of building damage citywide was in the Marina.
1
That leaning, sinking building, the Millennium Tower, should be renamed, "The Millennium Bug."
While we made it through that predicted digital disaster pretty unscathed, the actual physical effects of the bug may well be catching on in SF. That will be a real disaster.
4
Our cities are increasingly not working. They are too big, people are crammed too close together to have a sense of community, the services are breaking down, the budgets are out of control, and everyday people can't afford to live there. They are turning into rabbit warrens like Efrafa, from Watership Down.
4
Is this article meant to inform -- or just generate anxiety? My understanding is that most, if not all, of the skyscrapers in San Francisco are supported by piers/piles that are drilled through the soft soil and anchored into the bedrock 300 feet below street level. Why is this common, critical engineering component not even mentioned? The Millennial Tower did not employ this common technique, and therein lies its unique controversy.
It's also misleading to state that "a five-story building has the same strength requirements as a 50-story building," when the practical reality is quite different. Show me a five-story building with 300 foot piers sunk into the bedrock and I'll buy you a lifetime supply of SF sourdough bread.
5
Towering castles built on sand and already sinking: could there be a more perfect image for the city that silicon has remade? Or for the new potentates who have built it by turning the rest of us into marketable data? An image of heedless and soaring ambition after all, something those of us who knew the place years ago, and can sill remember coming over the top of a hill on a street car, gazing across a sudden prospect of low white wooden houses towards downtown and the bay, can barely bring ourselves to look at now.
It's interesting how we think about risk, and discount it when it's familiar. Temblors are terrifying because they're so sudden, arbitrary, and there's nothing much you can do if you're unlucky. They are like the vengeance of an angry deity. But lots more people in this country are likely to die of the heat, or the cold, or in traffic, or from the bite of some insect, or arachnid - than from the next PBO (pretty big one).
In the meantime, I will enjoy the 65-degree sunshine this afternoon - not a cloud anywhere. Don't get me wrong - our shed is stocked with provisions aplenty in case we're lucky, and if not - oh, well. Meanwhile folks, watch out for that Uber driver.
3
In the 80's San Francisco, the talk was the same, "the city lives on the edge", and "things happen in a big way here". It's part of the mentality of living there, on the edge. Everybody expects it some day, but not today, and definitely don't look up.
1
Gosh have you lived in SF? I have lived through all of the Bay Area earthquakes, Hayward Fault, and the Loma Prieta Fault and a few others. I cannot stand to be in a big building. I have a phobia about big buildings. We just don't expect the big one, our entire psyches change. The newcomers have many future challenges to deal with - no electricity or gas for weeks, no heating, no grocery stores are open, the banks ATMs are dead, you cannot get gas because the gas pumps aren't working. The list is extensive. I travel by bicycle. Air is my only bicycle need.
1
The liquification map clearly shows that FiDi, Embarcadero and Soma will have massive damage and loss of life in a big earthquake, as would most of the rest of the city. Interesting that the areas least prone to liquifaction - Telegraph, Nob and Russian Hills, as well as Pac Heights - are where the wealthiest denizens live.
It's not exactly a new notion to we natives that the rush to build up is not a good idea. The tech gold rush is already showing signs of fraying - a big one would send the industry elsewhere, as there potentially could be too much damage to buildings, infrastructure, and most tragically, loss of live. I work a couple days a week in SF, and whenever I think about the next big one, and look at the Benioff's phallic tribute to himself, and all that surrounds it, it all just smacks of so much hubris. And lots of other techies don't do much to dispel this image, either ...
6
Is any of these buildings covered by quake insurance ???
Never mentioned in the article
(Just wondering, after Woof's comment on insurance )
1
I am not sure, but California has eartbquake insurance available (I pay $1000 per year) and homes now are built to strict earthquake standards; for instance, house must be bolted to the foundation.
“Quake” insurance is like flood insurance along the Mississippi: theoretical, and unaffordable.
3
"Mr. Macris said the issue of seismic safety of high rises was “never a factor” in the redevelopment plans of the South of Market area, or SoMa, as it’s known."
Why in heaven's name was it not a factor?!? California is synonymous with earthquakes. Redevelopment plans in California, especially in densely populated San Francisco, should ALWAYS involve seismic safety. *SMH*
3
I moved to San Francisco 2 months before the 6.9 Loma Prieta earthquake in October 1989. One non-negotiable criteria I had when buying a home - not on landfill, i.e., must be on bedrock. Over the years I met several people who had lived in the Marina neighborhood, and lost their homes in 1989 because the "soft" first floor (garages) failed. Some buildings "pan-caked". A few collapsed and burned.
I am not an engineer or a policy maker. But I too worry what will happen to all those high-rises when the "Big One" strikes. Sounds like the experts aren't so confident either.
5
I lived in the Marina when the 89 quake hit. To this day I remember it like it was yesterday, and it's been nearly 30 years. There was severe damage throughout the neighborhood, and no buildings were more than 4 stories tall. Like you, I've opted to live on bedrock. I would never live on landfill again and, after reading this article, not sure I'd work there again either. My friends who were in Embarcadero Center that day recall it moved A LOT, and it's only half as tall as Salesforce Tower. I can't imagine what being on the upper floors of that building would be like in a quake.
3
A bunch of fancy graphics, but no mention of how the SF building codes compare to other earthquake-prone cities with many more skyscrapers than SF (e.g. nearly every medium-sized city in Japan, Taipei, Jakarta, Bangkok, and even Los Angeles). Japan tends to revise codes after learnings from major quakes -- still, a bunch of 60's and 70's era tall buildings managed to stay totally intact after the 9.1 Great Tohoku quake in 2011, including in Sendai near the epicenter. Many newer skyscrapers are being built on reclaimed land in Tokyo Bay which has liquefaction risks like downtown SF.
Is SF code up-to-date with the latest world-class standards? NYT editors, please revise.
12
Collapse-A-Roni (haiku) "We should be humbled - by earthquakes but we try to - outsmart them instead"
1
For buildings this tall, you've either sunk down to bedrock or you haven't...
The rest is commentary...
https://www.nytimes.com/2016/11/04/us/san-francisco-files-lawsuit-agains...
"...Engineers have questioned the wisdom of building skyscrapers with foundations in mud and clay. A skyscraper being constructed next door has made it clear that its foundation, unlike the Millennium Tower, reaches down to bedrock...
5
Great story. Appreciate the graphics. An additional graphic would make the story less alarmist, that being how many of those high rises are built on bedrock?
I live in SF. The majority of new buildings going up in the city, especially the high rises, have the same potential problem - facades of glass that will rain down on the streets should the tremor be of sufficient force.
13
"The goal of the code, say proponents of a stronger one, should be the survival of cities — strengthening water systems, electrical grids and cellular networks — not just individual buildings."
No. The purpose of building codes is life safety. Buildings need to stand and stay safe long enough for its occupants to get out and to safety. If your codes cannot accommodate that standard, they should be revised.
8
Didn't Frank Lloyd Wright figure this out theoretically with his Tokyo Hotel? And then his hotel floated safely above the big event....
It doesn't surprise me at all that all the usual suspects conspired to build as much as fast as they can. Bunch of minor league Trumpsters.
That's what also has happened in Seattle. We've had some astounding number of new buildings (500?) go up on every downtown block so that natives often don't even know where they are -- and the increased population density must rely on a street grid that hasn't ever been upgraded since the Seattle Fire, which is why WE'RE NUMBER ONE...in gridlock.
Completely predictable. PROFIT and GROWTH are our priorities.
We will run on money until it kills us.
Best post by an engineer: "The crucial fact is that if the epicenter/focus of a large quake (mag 7 or 8) is under downtown, (San Francisco, Los Angeles, Seattle, Portland) few buildings there today will survive."
Well, maybe we'll learn.
PS: Last time I was in San Francisco, we had a taxi driver from Hanoi and I apologized for all the people we killed in Vietnam.
"Is okay," he said, "too many people there anyway."
Ditto, obviously for LA, SF, Portland and Seattle. People = low priority.
Maybe we engage in apparently suicidal ways -- AR-15's, Slack building codes, wars -- in unconscious attempts to fit our numbers to our niche.
2
Every year we see a local documentary on what will happen when the big Seattle quake will hit and from what the experts tells us, it matters little what safeguards are put in place because everything west of I-5 will fall into the Sound followed by the giant tsunami.
2
As an architect, but not an engineer, I believe Lucy Jones might be incorrect in stating that "10% of the buildings will fall". It is not an inverse of the 90%, and it is not 1 out of 10 building is built inappropriately. There is a very small probability any buildings would fall based on this design approach. Yet, I stand with her that it should be set closer to 100%, maybe 98%, being realistic that 100% is improbable.
4
@Brian-
I wandered through Chinatown ten years after the 1989 Quake destroyed it.
Most pre-quake Chinatown buildings dated from the 1930s and 40’s. They were modest affairs by any standard — low-rise brick, wood beam, stucco and tile structures. Unlike the Marina District’s notorious collapses and infernos most of Chinatown remained standing, severely damaged.
Mortally wounded, actually. City building inspectors dutifully went block by block and red-tagged almost every one, and one-by-one they were demolished. Their replacements, although newer and seismically stronger, rented well beyond what most of the small businesses displaced by the disaster could pay. So, the unique shops that gave Chinatown its unduplicatable character, especially the idiosyncratic restaurants that I knew so well growing up in the East Bay — Sam Wo’s and Hunan just two of dozens, scores — disappeared. Big corporations moved in, but their Chinatown was a pale imitation of the original.
Although it remains a “must-see” feature on any tourist map, it was killed in 1989.
2
I've been in an earthquake and it was very scary. The adrenalin high lasted for hours. Chunks of concrete fell on me and I was knocked to the ground twice but fortunately not seriously hurt.
That was in Managua where a deadly earthquake flattened the city. The thing that really caught my attention was the high rise buildings: all of them were still "standing" - the four walls still existed. On closer examination there was no interior in any of them: the floors had all pancaked to ground level. Nobody in them at the time of the quake survived.
Then I took a close look at the Intercontinental Hotel, a truly quake-proof building. It is NOT a vertical tower; it is a pyramid. The windows are NOT vertically above one another like in skyscrapers; they are staggered so as to eliminate the propagation of vertical forces. California builders should take note.
6
That is why the Transamerica tower (building really) was built as a pyramid.
2
After Hurricane Sandy, I really started wondering about all of America's major cities. Many of them are built in high-risk disaster areas. Miami, LA, San Fran, New Orleans, Memphis, Oklahoma City, Phoenix/Vegas (just wait till they run out of water!) etc. This article, to me, just proves my fear that Americans are completely ignorant and have no respect for the the power of mother nature. I'd rather live in a one bedroom apartment that cost the same as a two bedroom knowing that my one bedroom was built to strict codes that will save me during a major earthquake.
2
When I lived in Phoenix, it is really surprising for me to know that wafer fee is way less expensive than electricity at a place where there water may run out in long run and sun light is pretty abundant. But after living for a longer time, I just accept the fact as other ordinary residents there.
1
I have respect for nature which is why i do not worry about if my apartment building is built to code. Nothing can withstand nature.
I have lived on the West Coast for over 40 years and have lost track of how many quakes I have felt. But if the big one hits Seattle, not only do I have the earthquake to worry about, I have huge trees planted all around that fall during rain storms and will surely topple during a quake. Then, there is the VERY real possibility that such a quake could get Mt. Rainier to blow its top unleashing a deadly lahare travelling at 500 mph towards the state capitol. Everything west of I-5 is projected to just fall into the sound followed by a massive tsunami.
Words to remember when the (next) big one hits — “ 'Buildings falling on top of other buildings — that’s not going to happen,' Mr. Klemencic said." — though no doubt Mr. Klemencic and other S.F. developers/consultants will have long before that moment taken their big cuts...
What I hear from engineers behind the scenes here in Seattle, where developers have also been building higher in an uncertain seismic zone, is that computer modeling allows developers to trim structural supports ever thinner, shaving costs but also shaving margins of safety.
All of us living in earthquake country should insist on building codes and where necessary retroactive adjustments so that, for example, more than one in four buildings in S.F. are *usable* after a big quake. Otherwise, when it does happen, whether in L.A. or S.F. or Seattle, hundreds of thousands or millions of people will be left without a city to live or work in, causing an unnecessary additional wave of loss and disruption.
6
The only way to know whether a real building will survive a real earthquake is to build the building and wait for the quake.
Once upon a time in Seattle, brick buildings were retrofitted with steel bars by drilling vertical holes through the bricks and cementing a steel bar vertically through them. This was considered quake-proofing at the time. Then an earthquake actually hit - and the bricks all shattered and collapsed, except for the ones cemented to the steel bars. So much for science correctly understanding earthquakes.
4
But we did come to know better. The entire point of science is not to know, but to learn. To never try any new technology would be like not letting your kids go outdoors until they were 20.
Also, chances are fairly high you live in a building that was physically built by people who would consider structural engineers to be over-cautious ninnies. Sleep well! :D
2
Is there a reason this in-depth piece on seismic safety omits our most recent large quake, the 1989 Loma Prieta earthquake? Seems like a major oversight.
10
I moved here 30 years ago and can unequivocally say that I would rather pick my stuff up off the floor once every 20-25 years after an earthquake than EVER have to deal with an East Coast winter again!
21
Great example of how poorly people understand risk.
1
@Chelsea - I think he understands risk perfectly well. Winter is guaranteed every year. A major earthquake? Not so much.
1
Wow,
As someone who has lived in New Zealand for the past 13 years and was in Christchurch for our series of earthquakes, this is shocking.
In Christchurch, a very small city by international standards with quite strict codes, we nevertheless lost 185 with two building collapses, not to mention masonry falling off the fronts of other buildings onto pedestrians and public transport, killing all but one passenger on one particular bus.
Furthermore, as the article points out, earthquake proofing means that buildings will survive intact enough so people can get out. That does not mean they are at all usable afterwards. Over 1200 buildings in the central city alone were demolished, some for structural reasons, some due to unstable foundations. I remember the Grand Chancellor Hotel leaning significantly.
This article has a good graphic on that:
http://www.stuff.co.nz/the-press/news/christchurch-earthquake-2011/66290...
Add that to the myriad of homes rendered unusable, and you set yourself up for an acute housing shortage.
Christchurch is a far smaller city than San Francisco, yet the recovery has been long, slow, painful and at times, bordering on incompetent and corrupt. San Franciscans would do well to read up on it and learn some lessons.
22
During the aftermath of Harvey we saw a lot of volunteers with and without boats aiding their neighbors. There was even what they were calling the Cajun Navy coming from all over to lend a hand. The problem is large cities, correction anywhere which could be damaged by naturual disasters cannot rely on just the National Gaurd and police to lend support to the people.
There's plenty of young men and women that can be organized as volunteers to lend a hand. There will have to be a national effort and no doubt dangerous. Cuba manages hurricanes much better than we do we can learn from them.
It's not just hurricanes and falling buildings we have to worry about. Can you imagine the disaster if water tunnels collapsed,water and sewer lines destroyed. Think about millions of people without drinking water. Im not saying the end is near but we should just sit around waiting when we can plan.
3
I keep an earthquake kit nearby. In it I have a water filter and I have tested it drinking directly from Lake Washington with no ill effects. On top of that, it rains almost everyday here so I will not worry about water:) I also keep a solar powered battery, lights, and close to a month worth of prescriptions. The pharmacist warned that after a quake, it would take quite a while to get meds in and distributed again.
I have been referring to Salesforce Tower as Hubris Tower for years now.
17
"Newer high rises across California, which are typically built around a concrete core, are designed using computer modeling." and then Thomas H. Heaton "perhaps the most prominent skeptic of building high rises in earthquake zones." is quoted saying: “It’s kind of like getting in a new airplane that’s only been designed on paper but nobody has ever flown in it.”
No, it's like getting into the Boeing 787. It was designed using computer modeling, not paper. It flies.
Building anything in a fault zone is risky, building on softer soils in a fault zone greatly increases the risk - but the question is "Does the construction techniques used meet the risk?" When Disney built their park in Japan, they build in an area where tremor-induced liquefaction was a great risk. They spent extra time compacting the soils beneath their structures and it was the one spot in that basin that suffered minimal damage from a later quake. Do California codes require steps like that? Do they require caisson foundations or attachment to rock below tall structures?
In the meantime, some risk mitigation worth considering is electrification of heating/cooking and removal of gas lines - a wood-frame house that stands up after the shaking only to burn because a nearby gas line ruptured is still a loss.
4
A 5-story building that is a construction type IA has the same code requirements, but a 5-story building is typically not built that way nor is it considered a high-rise. Type I buildings are the most expensive to build.
Most states follow the International Building Code (IBC) with their own state amendments. The California Building Code is based on the IBC. There are 5 construction types 1 through 5 and each has a Group A and B having to do with fire rating. A 5 story building could be 50,000 sq ft with 10,000 sq ft per floor plate. A type IB, IIA, Type IIIA and Type IVA also can have five stories in business occupancies. Most of the differences are in materials used and the fire ratings of walls, structural framing and floor/ceilings. California seismic codes in the Bay Area are the stiffest in the country. The film San Andreas was laughingly inaccurate. First we won't have a tsunami due to the location of our faults and the strength won't be as big as say Seattle which has a much deeper fault. Some say 8.4 as noted below however the Hayward fault which has the highest probability of striking (31%) should not be greater than a 7.4 M.
2
Great article about development in San Francisco, but could the reporters please correct the one factual error - Salesforce Tower is NOT the tallest building on the West Coast. That title actually belongs to the Wilshire Grand Tower in LA, which is 30 feet taller.
2
Thie first paragraph in total miss statement of how a ship come into San Francisco Bay.
I learned in graphics class in 1997 that animated graphics that you cannot stop are a no-no on a web page. What's up NYT, even advertisers know better!
6
The prize for today's "out of touch" statement is from Mr. Dean Macris, the head of the SF Planning Board back in 2004, "
“We saw that as a symbol of the new San Francisco and we wanted the building to be at least 1,000 feet in height,” said Dean Macris, a key figure in conceiving the new high-rise San Francisco who led the planning board under four mayors.
Now retired, Mr. Macris said the issue of seismic safety of high rises was “never a factor” in the redevelopment plans of the South of Market area, or SoMa, as it’s known."
I lived in SF for more than than I care to publicly admit, it was common knowledge that City Hall was under the thumb of Big business, developers and good old PG&E. Only one Progressive Mayor attempted to break free, Art Agnos, and they quickly ran him out of town. Here's more criticism of Mr. Macris, most of which we, in the area knew: http://sfbgarchive.48hills.org/sfbgarchive/2009/09/15/city-plannings-lat...
https://www.indybay.org/newsitems/2009/11/10/18628254.php
The mayor at the the time of the decision was probably Willie Brown who also ran the town during the famous Bay Bridge construction delay. Eventually that bridge caused several billion dollar cost overage. The leading cause was a standoff between two mayors over the "aesthetics" of the bridge, cable design or a more utilitarian design. Unbelievable. The other mayor is now the Governor. The SF Mayor after Willie Brown could potentially be the next Governor. Small world.
11
I love the Salesforce Tower for it's beautiful lines. I think it is a triumph for San Francisco. Disclaimer: I am a licenses architect in San Francisco
1
Gary,
I'm a 4th generation San Francisco native, and I agree entirely with your assessment.
San Francisco, for all its liberal veneer, is one of the most profoundly conservative places I've lived.
Has anyone read "City For Sale: The Transformation of San Francisco."
4
As a Geologist I assure you 'beautiful lines' have nothing to do with a buildings response to a great earthquake.
2
Not an architect, but isn't a deep foundation resting on bedrock the safest design for any building in an earthquake zone?
1
A foundation bearing on bedrock would certainly be safer than one bearing on soil, especially soils subject to liquifaction or soils that amplify ground shaking. That said, in an earthquake the bedrock shakes too so a deep foundation is no guarantee of anything. "Build on bedrock." is easier said than done. In much of the San Francisco area bedrock is 200 to 300 feet below the surface of the earth.
8
Pretty clear now that in a great earthquake many tall buildings in SF would topple as their foundations fail. Added to bridges, highways, pipelines, electric transmission, water supplies and sewer systems, all out indefinitely. Think NY City after 9/11, times a hundred, but without capability to rebuild before businesses go bankrupt. Businesses shut down and millions leaving with their homes mortgages abandoned, causing cascading economic failure. There is lots of planning that highlights the problems, but tiny budgets for preparedness, so the real problems are known but not fixed. The utter failure to adequately prepare ahead for earthquake recovery and safety is going to absolutely ruin California, Oregon and Washington.
1
Actually, it's very not clear. Since the when, where, and magnitude of the next major quake is a big unknown, the fate of SF is a mystery. The upside is that every seismic event informs improved building codes and general earthquake pareparedness.
Watching cheesy Roland Emmerich movies does not make anyone a disaster expert.
1
No earthquake will strike all three states at the same time.
One of the most devastating earthquakes in the northern/western hemisphere was in 1692 when the Jamaican City of Port Royal, the unofficial capital of Jamaica, sank into the sea. The quake has been estimated at 7.5 on the moment magnitude scale and about 5,000 people are believed to have perished from the quake, an ensuing tsunami and lingering injuries and disease. Modern scientific investigations into the loss of the entire city point to "liquefaction" as the main reason it was said at the time to have, "...just slipped into the sea." If you look at the map in this article that identifies the areas in San Francisco were the ground would liquefy in a significant quake, you only need to look back to the events 1692 to understand the catastrophic impact on population and infrastructure when the inevitable occurs.
3
In Tokyo, new buildings are constructed with advanced damping structures that absorb seismic energy, or with isolators in the foundation that protected the building above from motion. If San Francisco experienced earthquakes with the same frequency as Tokyo, I suspect we would build that way too. But who here was alive in 1906?
3
"“Ten percent of buildings will collapse said Lucy Jones,. “I don’t understand why that’s acceptable.”
Because, as I learned living in SF, everyone is convinced that if something big happens the Feds will bail them out.
Other people's taxes. Not theirs.
2
Tornadoes, hurricanes get bailed out. Evidently you feel only red states should be bailed out.
5
This is a disturbing article. Given the bitter political divide in the country, I have wondered more than once recently whether California, so vulnerable to earthquakes, droughts and fires, might under the current administration and Congress get treated like Puerto Rico in a major disaster. Far fetched? Well, there is already litigation between California and the Federal Government arising out of the Trump/Republican Crime Family's policies and the changes in federal tax deductions for state income tax was aimed squarely at California, New York and Massachusetts. I have said for years that the Civil War never ended so... if there is a bad 'quake in California (which I sincerely hope there is not), let's it occurs with Democrats in power. While nothing to brag about, at least the Democrats have not abdicated all civic loyalty and humanity in favor of profit and an "our thing" approach to the world.
3
@Mike-
They won’t treat California like Puerto Rico. After all, Trump owns a house there.
But the devastation to public transportation, energy delivery and life-support infrastructures might be so deep, enormous and far-flung that all the King’s horses and all the King’s men — everything the federal government mobilizes or could possibly mobilize — would prove insignificant in the short term.
4
The money shelled out to Texas and Florida is just a bandaid as nowhere is policy being re-examined to take measures to protect people from the next big hurricane. Puerto Rico's aid summarized in the image of Trump throwing out useless paper towels -- may equip itself better. They are in touch with reality.
Fascinating article and maps! I would like to see an in-depth piece just on the seismic issues confronting public infrastructure -- water systems, gas lines, train lines -- not just individual buildings.
One question the article raises is about how much more building costs would go up if we had stronger building codes, and it mentions "the average price of a home in San Francisco is above $1.2 million, even a marginal increase in price tag is bound to meet resistance." But this is misleading. Home prices in SF are high not because it is expensive to build new homes but because there are no new areas to develop, so the value of existing, very old supply of houses keep going up. It's the value of the land real estate, not cost of construction due to strong codes that are the reason behind high SF home prices.
How much would stronger buildings cost to build?
At a time when t
2
All San Franciscans are aware of seismic safety as precautions are integrated into building codes for small and large structures alike. Our water heaters must be anchored to walls. We keep a big plumbers wrench next to the gas meters for emergency shut-off. We shear-wall our ground floor spaces and bolt the structure to the hefty foundation. We keep emergency supplies. We research the geology of the ground beneath the homes we buy. Building codes are frequently re-written to improve safety.
What I don't understand is that here in California, where earthquakes are a possibility but rare, we take precautions. Many precautions. Yet in the South and the Midwest where there is a reliable annual onslaught of tornadoes and hurricanes, there seem to be no building codes designed to keep people safe.
Flimsy structures are flattened. Mobile homes, perhaps the worst place to live in a windstorm, are ubiquitous.
Hundreds of lives could be saved if their building codes reflected San Francisco's foresight and concern for public safety.
People here are pointing fingers at profiteering developers in San Francisco, but even though, with all the reviews and regulations, getting a project built here sometimes seems Kafkaesque, I'll take it over areas where building without appropriate structural integrity and concern for public safety is as normal as next year's tornado season.
6
I grew up in the midwest, moved to SF, then to Seattle. The only safe thing one can do in tornado country is get in the cellar and if you do not have a cellar, get in the tub. Pretty much anything else is getting blown to Kansas.
But the difference between quakes, tornadoes, and hurricanes is that one gets no warning with quakes. Tornadoes do not surprise a person. First it starts to rain, then thunder/lightning, then hail, then the sky gets an ugly blackish-green and starts churning like it is ready to hurl, and if you are still too stupid to have not taken cover, you might see a funnel form. But quakes hit and are over before you even figure out what is going on. People screaming in different languages, the ground rolling underneath you, with no indication how long or how strong it will be. And afterwards? The after-shock can be worse. Living in a trailer in the midwest is pretty safe compared to the best quake structures in SF because you get plenty of warning.
3
That's why moved from San Francisco to Seattle 20 years ago. Seattle has the most stringent building codes in the country. I keep wondering why so many SFO expats are moving up here...plus the tech companies???
1
Seattle's building codes are not all that great, and they can't even get around to retrofitting older buildings - they passed mandatory retrofits in 2013 but have yet to do anything, it gets postponed year by year. So far as I can tell from a quick Google, the new construction codes haven't even been tested in simulators, just based on failures in previous quakes.
2
I moved from SF about 40 years ago. Those stringent building codes will not help one bit if Mt. Rainier decides to rumble at the same time a tsunami is heading our way:)
1
I fell in love with San Francisco in the 1970s, when I was in my twenties. I always thought that some day I would have enough money to move there but the city became more and more expensive as time went by. It was so beautiful. Just the fact that the flower, fuchsia, loves it there made me want to stay. (Fuchsia dies in Oklahoma with the first 90 degree day.) I never got to move to San Francisco but I (sigh) have earthquakes now every day in Oklahoma.
18
My home is on the foothills above a large ancient lake bed. I have 3 major faults within a mile of my home on three sides. The ancient lake's shoreline is about 1000' further up the hillside from my house. Though the foundation of my 105 year old house has been retrofitted, the first floor is still unreinforced masonry. My property is at a slope. Basically, if there is a major earthquake (which is predicted could be as high as a magnitude 8.4) and we are home the best case scenario is we are all on the top floor (wood), the top floor separates from the rest of the house and we ride the sliding and dancing hillside down to the valley floor. Until then I will enjoy the view. I am sure I am not the only one who feels this way. The next big one is predicted to happen anytime from today to the next 1000 years. There is no sense is spending my life worrying about something I can not change. Beyond moving to a different state, there is not much to be done.
4
The newer skyscrapers are so close together in SF that the swaying caused by an earthquake will probably cause a lot of destruction. Wouldn't want to be near the windows when a next door building comes toward me to meet my swaying building! I grew up in California--the Bay Area--and at 73, I have experienced more than a few significant earthquakes. Few and far between, but definitely memorable.
5
During the great Mexico City earthquake of 1985 (moment magnitude 8.0) the resonance frequency of the seismic waves matched the resonance frequency of buildings in the range of 16 to 22 floors. (160 to 220 feet in height) Buildings in this range slammed into each other during the event. A rather horrific experience at the cusp on death.
3
I am a structural engineer educated at UC Berkeley. In the Bay Area I was shocked to see many seismically inadequate structures in daily use, including a friend's Berkeley apartment building that posted a sign at the entrance warning the building was not safe in an earthquake.
No building is earthquake-proof; we don't know enough about earthquakes for that. But I think the greater danger to life safety in San Francisco and other cities is seismically deficient older existing structures, and not the newer, highly engineered structures that are the focus of this article. These new towers may be badly damaged in an earthquake, but they will not fall. Meanwhile adjacent neighborhoods with unreinforced masonry buildings will be devastated.
The risk of injury/death due to earthquakes can be effectively reduced by rebuilding and/or retrofitting deficient existing structures, encouraging performance-based design approaches in new structures, and strengthening minimum code requirements for all structures.
Unfortunately I fear the irrational fear of new tall buildings and earthquakes encouraged by the sensational tone of this article (and seen in several comments below) will be happily co-opted by anti-development forces in their efforts to push back at efforts to increase density in San Francisco and other cities in seismically-active areas.
5
There is one paragraph in this article regards suspect welds on modern highrise steel structures. A deep examination of this issue by a major newspaper would cause great concern in L A and San Francisco. Check out the following:
http://www.laweekly.com/news/welds-apart-2130465
1
"newer, highly engineered structures" like the Millennium Tower?
http://www.businessinsider.com/is-millennium-tower-safe-still-leaning-si...
2
My daughter lived in one of those older small apartment buildings with an "unsafe in an earthquake" sign when she was an undergrad at Berkeley a few years ago. It worried me quite a bit. Her response - "Mom look at all the earthquakes it's been in already over the years and it hasn't collapsed yet". Not sure if that logic was really valid, but I chose to let it reassure me. Now that she is back in her hometown of Los Angeles, I still worry about earthquakes, but not quite as much.
1
Worries about building costs are misguided. To a first-order approximation, the cost of housing equals the cost of land plus the cost to build. The cost to build doesn't change a lot, but the cost of land does. If buyers are willing to pay, say $500 million for a building that costs $200 million to build, then the land will cost a bit less than $300 million. If the building has to be built with lots of safety features, then maybe it costs $250 million to build. In that case, the developer won't pay more than $250 million for the land.
Because of sky-high prices, San Francisco is perfectly positioned to demand safety features in its buildings. For the consumer and the developer, safety is *literally* free. Costs are borne by the landowner. And I'm not crying for the landowner, who has done incredibly well in the last 30 years by convincing the SF city government to restrict development, thereby driving up the value of his land.
5
Good heavens! It is unbelievable that they didn't even think about this when designing and building these high rises. I'm speechless. I recently went to a talk about the 'liquidifying ' of these soft soils and saw a computer simulation of what it would do to buildings on the east coast and it was terrifying. I had thought that soft soils would be better to absorb the shock waves, but it is actually worse. The other issue discussed was that most injuries from earthquakes are due to people running outside where they are then hit by falling materials from tall buildings. If I ever lived on the west coast (and I won't) I want a single floor structure.
I have an MS in structural engineering from UC Berkeley and studied seismic design. I am not an expert but I am knowledgeable. Much of the language of uncertainty in this article is intended to cause anxiety. But uncertainty is at the root of all science. It is all about working with limited data. This is normal.
"The profession does the best job we can to model and predict, but there are a number of uncertainties..."
That applies to virtually every scientific endeavor.
In the case of applied science, like structural engineering, it is also about learning from experience.
"Previous earthquakes have revealed flaws with some skyscrapers."
True. EVERY earthquake reveals flaws with past design solutions. And every earthquake provides additional experience which allows us to continually improve our designs.
Indeed the code does not specify that EVERY building be fit for occupancy after an earthquake. Buildings vital to recovery (hospitals) have the highest requirements. Your single family home has very low requirements. It's a question of cost. But anyone who chooses to is free to spend more to design above code.
Liquefaction: the height of a building has little relevance. The design of its foundation, regardless of its height, is key. A highrise built on deep piers will have more likelihood of less damage than a 2-story wood frame structure built on a shallow foundation, as was evident during the Loma Prieta earthquake.
54
The bigger danger, perhaps the biggest danger, is damage to infrastructure, not buildings.
California's infrastructure is in dire need of improvement. An earthquake could damage levees in the delta. If some collapsed, which is entirely plausible, huge tracts of land could be flooded in Central Valley. It could also cause problems right in the Bay from uncontrolled water flows.
San Francisco's drinking water system is vulnerable as well.
Old highway overpasses and bridges all over the state are substandard. A collapsed overpass on 101 or 280 could make movement of disaster relief traffic virtually impossible.
In terms of buildings, old unreinforced masonry structures are still the biggest threat to life. Lots of lower cost wood frame housing, built over "soft stories" (parking garages), will be lost as well, impacting poorer neighborhoods. I did my master's thesis on analyzing soft story residential buildings in Berkeley. Bad news!
I'm much more worried about these things than on the highrises.
If you live in San Francisco or the Peninsula I recommend that your earthquake plan be to drive out of the area. Plan to go to some other part of the state or another state, for several weeks at least. Plan your path out of the city in advance, and consider multiple routes, in case one or another route is blocked due to collapsed highway overpasses.
3
If I were to make 1 single recommendation regarding highrises in downtown, it would be to ban friction piles and require the use of end bearing piles. This would be expensive, which is why few developers do it.
The image in the article linked below about Millenium Tower explains the 2 different pile types. In liquified soil the friction coefficient basically goes to ZERO. So I don't know how geotechnical engineers can justify friction piles in liquefaction zones.
If any geotechs are reading this, I'd really like to read your responses on that point.
Scroll about 1/3 of the way down the page to see the image of the piles.
http://www.whablog.com/2016/12/08/that-sinking-feeling-san-franciscos-mi...
2
Most of the article is pretty silly fear mongering. But friction piles in a liquefaction zone seem crazy. I think the millenium tower is an exception but they just announced a plan that would cost 500 million to put new piles down to bedrock. (more than the building cost in the first place).
California has been very proactive about reinforcing infrastructure. Since the 1994 Northridge earthquake most overpasses have been rebuilt. Almost every hospital and emergency facility in the state has already been upgraded or replaced -- they are all required to meet a incredibly difficult standard of immediately usable after the largest expected earthquake.
San Francisco has two extra water supply systems beyond the standard fire hydrants (high pressure hydrants + cisterns) and both are being expanded currently. All apartment buildings with more than 4 units are currently being strengthened.
Fascinating read.
I regularly woke to minor quakes while living in Berkley in the 70's and the experience contributed to my departure - that sense that the plaster ceiling could crush me in bed.
I woke to a quake in NYC (mid-80's?) with the same feeling while living in an 1860's brick building supposedly built on bedrock.
Is there a similar map / graphic for NYC?
3
When housing prices are so divorced from construction costs, there is no evidence that stricter structural requirements would cause "even a marginal increase in price" ... perhaps cut into developer's profits, yes. However, since new construction will still be competing with existing stock it's prices must be in-line with that stock.
A developer pays a builder, and then rents or sells to a buyer, pocketing the difference. I have no objection if that difference is reduced to increase safety.
3
Oregon, Washington, Utah, and Colorado also have cities that are exposed to significant earthquake risks. Earthquakes in these states have occurred less frequently than in California, and generally with a smaller magnitude. The historical record does not reflect the longer term seismic risk. Consequently, residents of Portland, Seattle, Salt Lake City, and Denver are less aware of the risk.
Officials in these states take their lead from California and its building codes. As the article makes clear, these codes are intended to assure life safety. They are not intended to assure functional buildings after a major quake. Retrofitting buildings to the higher standard is costly, and most building owners are reluctant to bare the cost.
Retrofitting public buildings, highways, sewer and water lines, and other public infrastructure is a long term project that should be accomplished over the course of 40 to 50 years. However, public officials have other shorter term priorities, including the very large shortfalls in public pension funding.
The western states seismic hazard problem is part of the larger national problem of natural hazard mitigation. This is a topic that needs to be addressed sooner rather than later. It is not restricted to the private sector or the public sector. It effects every resident of the US.
6
Basic economics :
Issue building permits ONLY with the conditions that the building carries earthquake insurance that covers the building, and in, ADDITION, full liability for the damage its collapse might cause to people, infrastructure, and adjacent buildings
Leave it to the insurances companies and the builders to hash out the details.
5
Properties sold along the San Andreas fault line do have to disclose that to perspective buyers and I believe homeowners have to get said insurance. When I was in the 1989 earthquake our 5-story steel and glass office building shock from side to side (some glass damage) -- but my wooden structure home in Woodside, 20 miles south and west, sitting within 1/4 mile of the fault, suffered no damage. Nor did our community. Sigh.
Don't forget the fires--that is what destroyed San Francisco. All t he water mains broke.
11
San Francisco now is mostly covered by multiple redundant water systems. In addition to the standard fire hydrants that most cities have, it also is covered by a "high pressure" hydrant system that is seismically strengthened and operates only on gravity. Has pumps to use bay water, and has a growing system of large cisterns all over the city. All of the backup systems are currently being expanded and strengthened.
6
Randy:
In the 1989 Loma Prieta quake, the high-pressure system, the cisterns and the seawater-based Auxiliary Water Supply System (AWSS) all *failed* in the Marina. A hose had to dragged four blocks from an ancient fireboat (the Phoenix) to fight a large fire that could easily have gotten out of control.
4
Etaoin - Agree - but you also make the point that we have a 4th source of water to much of the city. The cisterns (they installed one on my block last year) are low tech - so less likely to fail. In the 1906 earthquake they were thought of as antiquated rements but prove critical.
As important is that the city is 90% through a program to retrofit the soft story apartment buildings which fell (and burned) in Loma Prieta. I noticed they are currently retrofitting the seawater pump at the end of Van Ness.
Interesting article, but I’m perplexed as to why it completely ignores or overlooks the 1989 Loma Prieta earthquake that hit SF with a 7.2. All of the newer buildings survived. Older brick ones tumbled. Hmm doesn’t seem to fit the narrative of this artlcle -I wonder if someone has an axe to grind here.
28
Loma Prieta was a 6.9, epicenter 60 miles away from SF in an uninhabited area. Its duration was short and magnitude low compared to a great quake, so not comparable.
2
The epicenter of the 7.2 Loma Prieta earthquake was about 70 miles south of San Francisco. Now imagine an 8.2 under the City. That's a magnitude 10 times stronger.
3
They aren't speaking of Loma Prieta-level earthquakes. They are speaking of much stronger ones, obviously. I was in the middle of Loma Prieta, closer to the epicenter than San Francisco by more than 50 miles. We got a few cracks in our walls. This is not anywhere near The Big One that is coming closer every day.
2
The issue of seismic safety was never an issue in San Francisco??
Horrifying!
2
Read Philip Fradkin’s, The Great Earthquake and Firestorm of 1906, for an enlightening account of human stupidity, hubris, and heroism in the face of catastrophe. Fradkin should be required reading for city planners and politicians!
4
This reminds me of (2) tragedies that struck the US close to home for me; one of which in my own home state:
One is Hurricane Katrina in 2005, which anyone born in this century knows of. My maternal great aunt lost her longtime home not far from Lake Ponchatrain in New Orleans, and was forced (or lucky enough; however you look at it) to move to Tenn. and live in a trailer shared by a family.
She died less than a year later; she was approximately 85 years old.
The other one which comes to mind is the worst natural disaster (so far) to strike the US Mainland: I am referring to The Great Hurricane of 1900 which struck Galveston Island head on. It killed somewhere between 8,000 and 12,000 people, and who knows how many injuries. It was so powerful the storm surge knocked a loaded passenger train that was 5 to 10 miles inland (Galveston is an island) clean off it's tracks, destroying it.
Coincidentally, my maternal great-great aunt survived that one (she was 3 years old) and lived to old age.
I mention these 2 tragedies only as a reference point. What if Hurricane Camille (1969), which struck Pass Christianne, Mississippi head on (right next to Gulfport, Mississippi. struck Miami head on? It broke all kinds of records and is the only "true" Category 5 hurricane to make landfall on the US coast; 1900 Galveston would have been. Also (I think for TV coverage)the rules were changed to the rating system to include Hurricane Andrew (It went from a 4 to a 5).
Imagine it hit Miami.
3
The Millennium Tower has sunk and is leaning 14 inches. That has got to be concerning. The fact that information in this story was kept from the public until recently in also concerning. And the fact that SF sits in the middle of a seismically active zone is certainly concerning.
18
And the issue of welds on highrise steel frames circa 1979 to 1994 is a MAJOR issue all by itself, which the NYT editors were made aware of two months ago. One wonders whether or not engineer Klemencic is aware of the fact that a huge lawsuit was filed against Lincoln Electric (mfct. of welding flux) by various L A office building owners in the wake of the '94 Northridge quake. That suit was quickly settled. A cover story published in the L A Weekly in the late 90's claimed that said welding flux was used on all highrises in California during the time period above. Point blank: the resultant welds are described as likely being too brittle to sustain severe seismic shaking in an extended/major quake.
what follows is a comment entered on the L A Times website in response to an article posted March 2nd regards retrofitting of buildings for seismic safety.
see also: Welds Apart
Welds Apart
By Greg Brouwer
Photo by Anne Fishbein When the Northridge quake awakened Los Angeles on January 17, 1994, it was considered at ...
"Too few major cities have been tested by major temblors."
Really? Here's a short list: Mexico City, Los Angeles, Santiago, San Salvador, Quito, Tokyo, Kobe, Chengdu, Tangshan, Istanbul, Tehran.
13
" Mr. Macris said the issue of seismic safety of high rises was “never a factor” in the redevelopment plans of the South of Market area" ...an area subject to liquefaction...,
That is an inconceivably shocking statement and article. Big real estate development has trumped (so to speak) most countervailing forces in today's political climate, but I assumed San Francisco would have been following state of the art earthquake management building design for tall buildings like those promulgated in Japan. This article does not mention those codes and how they might compare to San Francisco. Could you follow up? Why did the city insanely want the tallest building? How does ego and the perennial phallic symbol continue to trump (again) common sense and the safety of the public? If this kind of reporting has been done in the Bay area, I have missed it; bowing to the NYT.
21
The article notes the fire damage following the 1906 earthquake but fails to make clear that the fire, and the dynamite used by firemen to try and control the fire, caused most of the damage to San Francisco (maybe 90%; S. Tobriner, http://www.1906eqconf.org/plenarySessions.htm; NOAA, 1972, A study of earthquake losses in the San Francisco Bay Area - Data and Analysis, A report prepared for the Office of Emergency Preparedness: U.S. Department of Commerce, 220 p.). 1906 photos show an astonishing number of buildings that didn't collapse from earthquake shaking (https://oac.cdlib.org/ark:/13030/tf95801195/?brand=oac4).
3
The problem with the Millenium Tower isn’t its height. It’s that they didn’t attach it to bedrock. The problem with skyscrapers isn’t they are likely to fall over like books on a shelf. It’s the glass that pops out during a quake. Did you notice that in the picture from 1906 all the tall buildings are still standing? The real threat to the Bay Area? It’s Lake San Andreas and the Crystal Springs Reservoir. Here’s the scenario: the quake hits the San Andreas fault. The earthen dam holding back water in Lake San Andreas separates and then collapses and the water rushes into Crystal Springs Reservoir. The 110 year old dam there collapses sending a 100 foot high wall of water down the mountain and into Foster City. Thousands die instantly. To focus on skyscrapers is to miss the point entirely: Water, access, fire codes, housing, oh! And the lack of personal preparedness. I lived in LA for 8 years. I was the only person I knew who had an earthquake kit and emergency food supplies. The skyscrapers will be fine. The wood buildings in Sunset and Richmond with no firewalls between them? Not so much...
14
Good idea about earthquake/emergency kit. Mine is in a rolling suitcase. Plus about 15 gallons of water. We went through neighborhood training provided by the director of C.A.R.D. (Collaborating Agencies Responding to Disasters). Terrific common sense information that would make a world of difference if it was widely shared and people knew what to do. www.Facebook.com/MsDuctTape
1
RodA said: " I lived in LA for 8 years. I was the only person I knew who had an earthquake kit and emergency food supplies."
I live in NY now, but EVERYONE I know in LA has emergency kits/food supplies. I lived there for 25 years.
1
I keep a water filter in my earthquake kit. I used it for a year once when I was homeless drinking out of a local lake. A family could go through 15 gallons of water pretty fast. I also keep a solar powered battery kit in there along with extra meds. Rope, tarp, the other survival basics are included. And of course, my camping espresso maker:))))
“The profession does the best job we can to model and predict, but there are a number of uncertainties,” said Ron Hamburger, one of the country’s leading structural engineers. “We don’t have as many records, particularly for large magnitude earthquakes, as we would like.”
Uh? Who is we? The Chileans and Japanese have a lot of data on large magnitude earthquakes. Did you talk to them? Or are we so MAGA that we can't bother to ask people who don't look like us for help.
8
Modern seismology dates to the early 1900's. The earth is around 4 billion years old. How do we know 10 is the "max" on the Richter scale? The continents were once one single land mass. It is hubris to suggest we have any understanding of how powerful natural forces may be.
3
The Earthquake panorama used was actually taken from a kite, not an airship (though the photographer called it a "captive airship", he used a series of kites)
http://cabinetmagazine.org/issues/32/turner.php
5
I now live 14 miles north of San Francisco which puts me closer to the San Andreas fault. I grew up in Los Angeles have have seen what a 7.2 earthquake can do to a city. Never good. We were lucky that none of our taller building fell and it was luck not planning that saved them from falling. LA does not have a righteous city planning division and San Francisco is worse. Anyone with enough cash can pretty much build whatever they want. Millennium Tower is a classic example of cash trumps safety and common decency. The tower continues to lean and nothing short of demolition can save those who live nearby. No one wants to force the issue but mother nature will. Murphy's law is in full play here and we have a city government beholdenent to money that served up by a fire hose. A sandy wasteland on Mission Street and 16th Street will soon be home to 4 high rise towers 40 stories tall. That fabled neighborhood was once home to a rich culture now it's home to the very wealthy and they are racing to blot out the sun, clod the streets and make life for local residents a war where it looks like the homeless are gaining ground. The next big one promises to end this city's latest gold rush. We are still cleaning up from the last quake so it's perfect timing for Murphy's Law to lift its head and shake us from our foolishness.
13
Paradoxically, the 1987 Loma Prieta accelerated development by blowing away the highway over the Embarcadero. A few minutes after the shaking, properties facing the Bay were suddenly much, more more valuable. Ask the people who own the YMCA building or the Hill Bros complex (where Google has its city offices).
Whatever happens the real estate developers win. Build 'em cheap so they'll fall over. Build 'em again when they've fallen over. (Repeat).
1
I must correct this oddball letter: SF sits atop a fault. Mill Valley, a wealthy suburban town 14 miles north, does not. San Francisco has strict city planning codes and building here, even with buckets of money, likely requires more hoop-jumping than any other U.S. City, certainly more than in suburban Mill Valley. There are no sandy wastelands at all in the dense, built-out part of SF near 16th Street and Mission, much less room for four towers "40 stories tall." The last quake that caused significant damage was a 6.9 in 1989. Cleanup efforts are long completed. I've never experienced "money that served up by a fire hose" here, but the thought is fun, in a Freudian sort of way.
Earthquakes are always in the back of our minds. Even a shift in the wind or the stillness of the air will make us flinch and then tense-up. I have lived through many during my 70 years of life, and they are indeed frightening. Geologically, it is a wonder that we are not submerged in the Pacific Ocean by now. In fact, we consider ourselves lucky if we "merely" have items shaken off of shelves, pictures on the floor, and cracks on our ceilings. But what are we to do if our livelihoods - and lives - are here in the Bay Area. We just do what we can afford to do to fortify our property, and, well, pray..
9
Great interactive article.
I assume the newest skyscrapers have been through computer simulated earthquakes. What magnitude are they designed to endure? And how often do earthquakes of that size occur in any given area?
How typically American that we build the most densely-populated buildings in the most threatened area of the city.
It doesn't really matter what the cost of retrofitting these buildings is; it will be considered a worthy investment when the Big One finally hits.
It would be interesting to see this same reporting applied to Portland, Seattle and Vancouver BC, since it's become accepted fact that they too are sitting on an area extremely prone to violent quakes.
Suddenly my little one-story brick 3-bedroom in rural Georgia doesn't seem so bad!
3
:) I live in Seattle and watch back east get hit with tornado after tornado, hurricane after hurricane, blizzard after blizzard and will stay here with an active volcano in plain view. We RARELY hear thunder or see lightning, we had a real cold snap this winter where one night it gone down to 25 degrees, and we whine if it gets over 80 degrees in the summer.
I am in far greater danger of being struck by a foreign missile than having a building collapse on me during the big one.
Humans, American ones in particular, California ones especially, have no understanding of the concept of "carrying capacity." Environments can only hold a certain number of organisms in a safe, sustainable & healthy manner. Unfortunately humans have developed a remarkable ability to artificially override carrying capacity. Simply put, there are only so many people that can live in San Francisco.
This is not only about food, water, & disease. In San Francisco's case, the sesimic geography takes on special significance, imposing limits to what can be built that is both safe and economically viable. Thoughtless construction in that environment will have spectacularly tragic ramifications. Failure to acknowledge and respond appropriately to this situation has a name: Hubris.
6
Before reading this article I was opposed to the folks in California who want to leave the Union and form their own country, now I am not so opposed, one less cost to share with the east coast. Maybe part of the reason Draper has proposed splitting California into 3 states
1
I'm kind of surprised the article did not address Japan at all. Think about it: Japan is known as an earthquake-prone country, its cities have high population densities, and their building codes are (to my knowledge), fairly strict and designed for safety during an earthquake. I am guessing that what makes skyscrapers in Tokyo more tenable than skyscrapers in San Francisco is the soil quality.
15
New York City is built on bedrock so if a earth quake did happen there would be very little danger of a building falling down.
Hubris and greed will be the downfall of San Francisco. There is so much ego in this 7 by 7 mile space, it's breathtaking. If the local government were sincerely interested in this issue, they would have stricter building codes for tall structures and offer tax incentives to those who own existing buildings to do necessary retrofits. Instead, the city has been sold to the highest bidder and the quality of life for residents is an afterthought.
5
On e thing is for sure- the US Army will not be in the neighborhood to help like they did after the 1906 Earthquake. After that event, the US Army was deeply involved in feeding, housing and providing other critical services from The Presidio and it's nearby outlying installations. You can read about it many places like here in the National Archives:
https://www.archives.gov/publications/prologue/2006/spring/earthquake.html
The geniuses on the Base Realignment and Closure Commission have systemically closed virtually every US Army installation around San Francisco Bay to include the Presidio. If you look at the map of vulnerable land, you will see it was located on some of the least risky land in the city.
1
This article confirms what I've always felt about Seattle: that the safety of our current building codes and retrofitting efforts are mostly theoretical. Meanwhile, the city is densifying everywhere, as Amazon, Google et al have fueled a building boom that dwarfs what happened when Microsoft arrived.
Some years back we finally decided to replace the Alaska Way Viaduct, Seattle's version of SF's Embarcadero. But we doubled down on our beliefs in modern engineering vs liquifaction, and are building an underground tunnel in the same location: the filled-in mud flats of Elliott Bay. I won't be using it.
4
A possible scenario is that the fill areas will be under water before there is a big earthquake. Then maybe they should be thinking about getting those big buildings horizontal, so they can use them as boats.
On the statistics--probability as to what will happen in an earthquake: First, some of your experts say, "We don't know.", too many variables, and we don't have comparative data. Using available data, pick a dozen buildings, look at their location and specific earthquake protections, and tell us what is likely to happen. Especially do this for the millennium bldg--how much will it take to push it over; which way will it fall, and then what will happen?
What are the plans for fire protection--water--in the event of a major earthquake?
Look at the new Bay Bridge. How is its design better able to withstand an earthquake than the old bridge. How have similar bridges done in an earthquake. The old bridge withstood an earthquake in 1989 with only one section separating and collapsing; why was it replaced and who paid for the cost overruns?
On the map there is a red zone just south of the tennis courts in the park. Why? This is on the side of a hill.
1
I left a few years ago where I had stated that they have to stop building taller buildings.
I was attacked as being ignorant.
I am far from being ignorant on this.
I have a degree in architecture from Pratt Institute that I got in 1976.
I will admit my education did not include anything about earth quakes but it did give me a understanding of structure that told me most of the findings based on models could be wrong.
Most of the taller buildings will not fall down but because earth Quakes are not always the same it is possible forces can be placed on the building that was not anticipated by the scientist who told us these building were safe based on the experiments they did on models.
They built models and then shook them to see if they would fall down.
The results were very impressive.
They didn't convince me as a model of a building is very different from a real one and shaking the model can duplicate most of the forces that occur in most earth quakes that can make the building fall down but not all of them.
I saw no great need to put up building which are not needed on the West Coast that would justify building that tall.
This is not true about Japan because of the population they have on a land that is much smaller than ours .
Nothing has changed so I still feel the same.
Sometime in the future there will be a earth quake that will prove me wrong or right.
I hope I am wrong.
5
Unfortunately, you are not wrong. Do computer models of a building's performance in a quake account for too brittle steel welds resulting from suspect welding flux?
3
Bay denizens such as myself just try not to think about the "Big One," but we all understand that it is overdue and will certainly come in time. But I would not want to be at the top of one of these new skyscrapers when it does.
2
Amazing that in an article devoted to construction for earthquakes, another great wold city, Tokyo, which has designed buildings to withstand earthquakes is not even mentioned. Tokyo is in a seismically active part of the world with numerous earthquakes and regular tremors which constantly test construction design in real world conditions. Are our American egos so out-sized that we think that graduate students pouring over plans of already constructed buildings can do better that reviewing architects and designers who build in real world conditions? This article was not worth reading.
5
Obviously, you are famiiar with soil/ground conditions in Tokyo, as well as the issue of suspect (brittle) welds welded circa 1979 - 1994 on all steel highrises in California. In the wake of the '94 Northridge quake, L A region building owners brought suit against the manufacturer of questionalble building flux. Said suit was quickly settled and so so many steel frame highrises have not since been retrofitted.
1
In the 2011 earthquake in Christchurch, NZ, there was considerable liquefaction esp. in the eastern suburbs; those areas were abandoned. NZ has the most stringent building codes to deal with earthquakes.
2
The high rise office towers at Embarcadero have been through two sizable earthquakes without damage. They use "base isolation" to minimize shaking of the structure, but they are nowhere near 50 stories either.
They are located in what was the old harbor, as in "the water part". The "land" underneath is bay dredged sediment over the hulks of rotting wood hull ships from the Gold Rush era.
I was in my 25th floor office when a 5.6 struck, and sitting in a rolling office chair which stayed more-or-less stationary while my desk and file cabinets moved 5-6 feet back and forth as the building swayed. I was "safe", but shortly thereafter changed jobs to work in a 4 story building..
49
I'm a big fan of John Portman and the Embarcadero. His use of repetitive materials (and easily replaced) his circulation movement and different levels, his use of water. It's a fabulous design and holds up.
A 5.6 magnitude moment (MMS) earthquake is small relative to the much larger >8.0 MMS 'great' earthquakes the San Andreas Fault has generated. The Loma Prieta event was 6.9 MMS and the epicenter was about 85 miles south of San Francisco. Architects and Engineers profess adequate knowledge in design for seismogenic regions -- Geologists and Seismologist are far more conservative. Which perspective is 'correct'? We will know in time.
2
A bit bitter after being priced out of my home there post-divorce, I look at the San Francisco of 5 years on and sigh. The City I lived in for 20 years has changed so much, so fast, and not in ways conducive to raising a family there, with schools, teachers who lived in the neighborhood, many children and seniors. I'm hoping something changes. But I digress...
Those tall buildings scare the living daylights out of me, though I worked in the bowels of 555 California for quite a while at the Bank of America Corporate Archives. Now I come back to SF to work, at various spots, whoever will pay me to gather their historic materials, and I interface with The City and its people and institutions over many decades. I've seen them all go up. The massive TransBay Terminal project was once a bucolic area of tree-lined streets. Mark Twain wrote in his journal about the nice neighborhood where he lived on Minna St. When I lived there until the construction started it was pretty much a grim area. In that respect, it's been an improvement.
Yep, they could get spanked by that tectonic monster any time, and some day again they will, but it may be the the sea gets rid of those skyscrapers first. 150 years from now the Pacific will rise enough that parts of that area will be underwater anyway. I imagine my former house on 47th Avenue will be. Eventually San Francisco will be an archipelago. 555 California will be part of the Silicon Atlantis.
8
The 2011 earthquake in Christchurch, NZ resulted in considerable liquefaction. the eastern suburbs were particularly hard it with liquefaction. They have been abandoned.
1
I was rather bemused by the stated desire for an "iconic" building when discussing the Salesforce Tower. Maybe I'm just showing my age, but the Coit Tower has always been a good enough 'icon' for me! Great design for this article, thanks!
4
There has long been a disconnect between modern humans and common sense. Not sure when it happened, but maybe because our ancestors (and even some indigenous people in less developed countries) didn't have an expansive government and insurance system to clean up the mess, planning used to be much more instinctual and for lack of a better word, accurate. At the very least, previous generations of humans learned from their mistakes and wouldn't build on quicksand twice in one generation.
2
Given the expensive real estate, it makes a vertical downtown inevitable. We should look at how Japan and particularly Tokyo handles it where real estate is also a scarce resource.
3
Since they are a country that has over 1000 earthquakes per year, Japan has always spent far more time and money than the U.S. to investigate and innovate ways of dealing with these important issues. Even their high speed trains have systems in place to deal with earthquakes and their possible damage. For the sake of making a quick buck, it seems America and its business types always looks for ways to get around whatever rules are in place and this is just another case in point of Republicans dismantling regulations that affect safety. it always comes back to the importance of public policy.
The article didn't specifically mention it, but, The Millenium Tower in SF is a condominium so how would one feel if they were an owner in this building and the value of their investment was disappearing before their eyes?
4
No doubt about it, earthquakes are completely unpredictable.
One house can be fine and the neighbor completely destroyed.
Often makes no sense.
However, not so many years ago SF did experience a 7.2, which I experienced first hand. It was devastating and tragic. People died, buildings burned (mainly in the Marina) and yet most everything held together. We're still here.
In fact that earthquake and subsequent dismantling of the Embarcadero freeway brought about the rebirth of a major portion of the SF Waterfront, just one example.
Even after reading this piece, I am still moving my West Coast office into the SFT this Summer.
Great maps. Glad to see my residence is in one of the lightest of zones just south of the Presidio Wall.
3
Except the epicenter was 100 miles to the south in Santa Cruz. Had it been up in SF proper...
3
"But the city is also putting up taller and taller buildings clustered closer and closer together because of the state’s severe housing shortage."
i find it difficult to believe that *any* of these new buildings are built to provide additional housing... particularly any *affordable* housing. i live in NYC and the drive for "redevelopment" and "business improvement districts" (such as the Hudson Yards development) will benefit any of the working class or working poor in our city -- or in San Francisco. i have always wanted to visit SF because it looked like a charming, livable city. now, it looks like every other overdeveloped modern city. i fear i will see the destruction of most cities either by fire, flood, or earthquake or other natural disaster within my lifetime.
18
"...the vast power and mysteries of earthquakes should continue to instill a deep humility." Ahh, a word rarely used these days, humility. Instead, we constantly deal with another h-word, hubris.
Why, the buildings are designed by computer, what could go wrong? Lots of things, in untested "theoretical" and real world cases that many, apparently, would rather ignore than address. While building materials may be stronger - and that may be a false security especially if it turns out that the material "didn't perform as expected" or was manufactured in China and actually was defective to begin with! Flawed steel has been a problem for years but we are just to assume that everything is okay. Toss in a generally lower quality of construction by an industry that is struggling to find qualified workers and its a frightening mix.
California, especially LA and SF, love to portray themselves as the paragon for much that is ideal. A natural beauty, however, does not compensate for arrogance in politics and actions. The dangers of earthquakes are known to everyone yet that is ignored while the state and municipalities put their focus on fighting DC or acting as if they should be their own country. Poverty, homelessness, lousy education and infrastructure, and now this story, all illustrate that the golden part of California is often a sham and with cheapness below the glitz. California needs desperately to get its act together.
7
And yet, we feel compelled to approve of the wasting of thousands of people in the prime of life--our military--and tens of thousands of debilitating injuries to them; and to spend trillions on wars that are unproductive. We allowed the Robert McNameras and the Dick Cheneys to convince presidents that we needed to fight in Vietnam and the Middle East. We voted down and assassinated leaders who were for peace. We have our priorities, and the quality of people's lives is not among them. Today, my nice real-wood, Flexsteel bedroom set comes from--Vietnam, it turns out! We have the money for infrastructure, schools, medical coverage, research and a cleaner environment. But war is more compelling. Because war is business. "The business of America is business." IE, war. Fear starts wars and the business of war keeps them going. Then there is the awesome power of human denial and avoidance and procrastination. So the problem is us. Can we overcome our destructive tendencies? So far, no.
4
Truly. Think of all the improvements that could be made if the money dedicated to "keeping us safe" were redirected to local schools, hospitals, housing, parks, etc.
The irony is that the trillions spent on wars has turned the middle east into an international terrorist factory. With this and DC cowering to the NRA, we're less safe than ever, and poorer and dumber.
4
In The Rolling Stones song “When the Whip Comes Down” the lyric goes “when the s... hits the fan, I’ll be sitting on the can.”
How prescient the boys were when it comes to a 1906 or larger size quake hitting SF again, which it will, and all those folks are living and working in high rises that will come down like a house of cards.
1
NYT map designers do phenomenal work.
177
except they didnt include 181 Fremont at 802 ft and the second tallest bldg in sf. Foundation down to bedrock.
Ultimately, mother nature is undefeated. Sure, building codes should make buildings as safe as possible and should also be as rational as possible. However, if a big enough earthquake strikes, any building, no matter how perfectly engineered or constructed, could be at risk of severe damage or collapse. It's foolish to think that we can write rules that will protect us from nature, which operates under a set of rules that makes our own rules and plans laughable in comparison.
2
California's housing and building woes are self-inflicted political problems.
South-of-Market is made of fill (euphemism for heap of debris from 1906) and known to be a terrible place to build skyscrapers, since there is no bedrock. But they figured the Millennium could use a "floating" foundation of pillars without being anchored to anything. You don't need a PhD to understand why that is bad, and now the results speak for themselves. Contrast to the TransAmerica pyramid, which is built on solid ground north of market and involved serious seismic engineering. Why can't people build more skyscrapers there? Becuase nobody wants to tear down existing 3-story Victorian houses. Contrast to NYC, which has been continuously tearing down and building higher for 100 years or more.
And then there is housing... you can't build yourself out of a housing crisis with skyscrapers. More realistic would be thousands of 5-10 story earthquake-proof apartment blocks. But again, that is not politically possible in CA.
Until CA is willing to "change the character" of existing neighborhoods, it will continue to build dangerously substandard skyscrapers on fill, while leaving the average Californian practically homeless.
3
"there is no bedrock..." is actually a false statement. There is bedrock in SOMA but it is down farther than in other places in the city. The proposed fix for the Millennium Tower is that they will actually retrofit the tower with pilings that go down to the bedrock. The designers of the MT could have played it safe and gone down to bedrock but decided to gamble on a new approach to save money. Unfortunately for the owners in the MT, the gamble didn't pay off. To me the lesson from MT is that sometimes there is a reason that playing it safe is the way to go.
10
There is bedrock, but the Millennium Tower foundation structure doesn't go deep enough to reach it.
As this article is trying to convey, there is no such thing as "earthquake proof." The Victorians that define San Francisco were constructed mostly in the 1880s and 90s and survived the 1906 earthquake. That's fairly "earthquake prooof."
2
The amount of public and private money squandered on "earthquake safety" is both shocking and shameful. The greatest thing that could happen to California is for everyone who is afraid of dying in an earthquake to leave the state for "safer" places to live. The resulting reduction in population would be worth every minute of earthquake angst to those of us willing to take our chances.
1
Fine. Don't spend any more money on earthquake safety. But if a big earthquake strikes, don't ask taxpayers outside of California to bail you out.
1
JMC - The design here does not take your chances, it takes everyone's for them without asking. I am sure you are trained on the side as fire & rescue ....
2
Of course this is not true. A good share of construction and almost all required retrofitting costs are for earthquake safety. SF has stringent seismic standards, counter to what this article implies.
California is a donor state, so if you are in a recipient state (most red states are), we're already picking up the tab for your lunch, so don't be jumping to false conclusions and try not to think about the next tornado.
This is just one more of a hundred different reasons to not live in or visit the San Francisco Bay area.
6
Why do you presume anyone wouldnt presume that actual safety in this massive-earthquake zone long ago took a back seat to development? Which is precisely what has happened. When the Big One hits, the whole no-one-could-have-predicted-the-utterly-predictable excuse will be trotted out.
2
“It’s kind of like getting in a new airplane that’s only been designed on paper but nobody has ever flown in it..."
That would be the Boeing 777. Which has the best safety record of any airliner.
3
Yes, but the 777 was throughly tested by actually real-world flying before it ever carried a single revenue passenger!
6
Human beings are notoriously poor long-term planners. For most people, their long-term planning begins and ends with hoping and/or praying.
3
Salesforce Tower is not, and was never, the tallest building West of the Mississippi. The Wilshire Grand Center in Los Angeles is taller by roughly 30 meters and topped out in September 2016, 7 months earlier than Salesforce Tower.
6
I think it's taller because it has a stick or antenna or something like that on top. But they're both ugly.
2
It's only a matter of time until another 8+ Richter Scale quake hits San Francisco. Much of the city is built on landfill from the first quake in 1906, and it will slide into the bay. When it does hit, it will make the '06 quake look like a minor tremor. The only saving grace for San Franciscans is that homes and businesses are no longer built of all wood, thus reducing the fire hazard that wiped out much of San Fransisco after the big one in 1906.
2
Huh? Not made of wood? You bet they are.
1
San Francisco is a time bomb. Perched on the San Andreas Fault, a major seismic event is inevitable. It's just a matter of when.
2
First what a wonderful job NYT is doing bringing an article to its readers in this fashion, thank you. Living in Istanbul with 15+M people and a lot of substandard buildings most are being torn down and rebuild to higher standards but still so much more to go. San Francisco seem way a head of the game here but the liquification risk appears to be much higher there.
1
Fascinating. And alarming.
Excellent maps and graphics, as well!
In 1976, I took an intro Geology course which featured a film San Francisco: City of Doom. 'Nuff said.
1
I'm surprised the writer didn't mention the penchant for overhanging glass in almost every single building in the financial district built in the last few years. So now not only do you have to worry about a potential building collapse, but the showers of glass shards that are sure to accompany even a minor quake.
5
Totally agree with you. I was in downtown San Francisco during the Loma Prieta earthquake in 1989, and the glass coming down from some of the high rises injured many many people.
1
The glass is usually tempered glass, which doesn't shatter.
1
San Francisco or, rather, its inhabitants are victims of human greed and disregard of the probability of natural disasters striking. One sees the same on the slopes of Mount Etna in Sicily, where new vacation homes are being built on recent lava flows and on some seashores, where coastal erosion and rising sea-level are ignored by home owners.
2
One of the issues I never see addressed is the glass in tall towers. How much movement can the window gaskets take?
The purpose of the codes is life safety. Getting you out alive after a major earthquake is more important than the perhaps unachievable and unaffordable goal of keeping a building functioning. There will be economic consequences for the the city not functioning. That is just the way it is. But you will be alive to deal with that.
The statistic on buildings lost in 1906 points to the fire, however, a San Francisco librarian did extensive research and found that more buildings were lost from the earthquake and powerful people preferred that the fire be considered the prime problem.
1
This seems far-fetched. The worst quake damage was to brick and masonry buildings in the downtown area while wood-frame Victorians, because of their flexibility, withstood the quake with relatively minor damage. This is true for the huge, ornate Victorians atop Nob Hill (adjacent to downtown) where the richest San Franciscans lived. It was the fire, however, that destroyed their mansions. The quake had severely damaged the city's water system, which hobbled firefighting efforts.
In our combustible wooden city prone to quakes, we downplay neither earthquakes nor fires.
Why doesn't the city (one of the wealthiest in the country) pay for a team of Japanese engineers to come and do the assessment? It is amazing that the engineers and planners wouldn't want to learn from another culture that has weathered the same problems. The 1,070 ft Salesforce Tower is literally the height of hubris...
12
The best they can hope for is that science finds a way to forecast the next serious one. For now, 'live like today is your last', could be a new tourism slogan for the area.
1
All those wood frame structures you talk about briefly that will do well in the next big earthquake in San Francisco will face another testsoon after.
Those in the western section will all burn to the ground in a firestorm. VERY knowlegable people have been trying to get The City to expand the high pressure and seperate water system which was built after 1906 to the west side of The City. The 600M cost is allowing the political types to seek other so-called remidies for it. It will not work and the west side of San Francisco will burn to the ground. Go take a good look at that issues as it will dwarf a dozen high rise buildings going down in its impact.
1
Living in the East Bay, I am shocked every time I make a trip to San Francisco by the size of these monster buildings. I moved to the Bay Area from the midwest in 1960, when the city was alight in the sun, and the buildings were much smaller. I have thought again and again that the new high-rises are a mistake, and now I see that nobody "in charge" cares.
23
You should move.
1
I've lived in California all my life and gone through many earthquakes and am always reading about them. Otherwise, I've noticed that I never really think about them until only when they're actually happening. But after that the thought of them goes away quickly again because putting everything back on the shelves and straightening out the pictures takes up so much time. What's worse? No place to hang the picture in the first place, or having to straighten it out later on? Such is the dilemma we face in all of life.
This is the gambling of people's lives, homes and livlihoods -- not to mention a beloved city -- for the sake of making a few very developers wealthier than anyone ever needs to be, developers who will be long gone from the scene of the crime when another earthquake inevitably strikes. Hasn't anyone been paying attention to the number of so-called 100-year floods -- that are now happening with far greater frequency than anyone predicted? 1,000-year earthquakes? Bah! Where are the outraged city leaders?
As a structural engineer who has practiced in San Francisco most of my 30 year career, and Executive Director of the US Resiliency Council, I can attest to the improvement of codes over the years. Unfortunately, designing a building is not like designing a car or a widget. Given the cost, each building is its own real life test case. We learn from each earthquake and continually make improvements.
Not mentioned in the article, but of perhaps even more concern, is that in cities like San Francisco, Los Angeles, Portland and Seattle, upward of 90% of the existing building stock was built BEFORE modern codes, making them especially vulnerable to extensive damage, even collapse in the Big One.
Assemblyman Nazarian, mentioned in the article has introduced a second bill that would require cities in CA to inventory their older, vulnerable buildings, so that communities can develop long term mitigation and resilience strategies.
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How did the buildings in Kobe hold up? That might be the nearest equivalent to a powerful earthquake in a major city.
Northridge and Loma Prieta were powerful, but they were not the "big one". If a Kobe-style quake hits SF, it will be 6-feet deep in broken glass even if the buildings don't fall over. There is already a 40-story building that's starting to lean over even without a quake.
I expect that it is the expectation of those in San Francisco that the Federal government will bail them out, rebuild the entire city, perhaps better than before all at the expense of the Federal government.
So at least as to property loss, the gamble might be view as political rather than seismic.
2
No, it is the expectation of San Franciscans (and Californians as a whole) that we will continue to pay more in taxes than we receive in tax benefits. You ought to know the feeling: Illinois is in the same boat, paying more in federal taxes than they receive in federal aid, although California, with nearly two and a half times the state GDP, shoulders a proportionately larger share of the load.
9
Like Houston is being bailed out for having a subpar building code for floods/hurricanes prone to its area? I don't disagree with your point, but wanted to mention that subpar building codes and an expectation for bailouts (whether it be for earthquakes in a blue state vs. flooding in a red one) is nonpartisan.
5
Another perspective: maybe intense clustering of people in big cities is not a good idea. Despite our subjective desires for city life, and some practical efficiencies, high density population centers pose greatly elevated risks.
For northern California, with unavoidable earthquakes, low-rise structures and more distributed small population centers might reduce the impact, simply with fewer people living in any one area most impacted by the next quake. For places like Texas and Florida, with hurricanes and flooding, clustering all the people in one place can result in all-or-nothing devastation. And for all cities, any human-induced event, intentional or not, will have an amplified impact.
4
We could cover Northern Cal with suburbs, and make the freeways bigger. I'm afraid with 8 billion people (340m of them in California), building up is the only way to preserve any open space.
True but the question is how high is high enough.
Building very tall building(especially office buildings) do not give you as much land to preserve open spaces as tall buildings are very inefficient because of the need to have elevators that can take you to the top in a short period of time.
I did not know there were 340 million people in California.
I thought that was the population of the entire country.
1
@stone. My mistake on the population. Only about 35m in California (subtract one 0 from my original figure).
Taller buildings are more efficient to heat and cool, and they use a lot less land surface area, but there is the problem of elevators. Of course, to move that many people that far across the surface would also require energy. Most elevators have counterweights so that they are close to neutral except for the weight of the people in them. It still takes some energy to lift.
I wonder if they have studied the building codes of Santiago, Chile? Or Tokyo? Or Jakarta? or Lima, Peru? These places have all suffered and grown from earthquake experiences. Santiago has many high rises now, and have VERY stringent codes. Good luck, California!
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The same thought occurred to me. The article does omit the fact that many areas with tall buildings have suffered earthquakes. There is a lot of data on which to build models. To imply that no one really knows how these buildings will perform is an overstatement. The tone of the article struck me as irresponsible.
The Millennium Tower’s foundation was an exception, or it is at least billed as the exception. Certainly there was much noise about the fact that the Salesforce Tower’s pilings went down to bedrock. I shouldn’t wonder if a lot of high rise owners whose foundations/pilings complain.
While driving home to the East Bay on the underside of the Bay Bridge a few years back and crawling along in the inevitable traffic, my daughter asked me what would happen if an earthquake struck at that moment. Wouldn’t we be the meat in the sandwich? I couldn’t disagree. I love the Bay Area, but I don’t miss the angst of waiting for the “Big One”.
21
The article doesn't quite capture the political aspect of seismic design. In voting to ratify seismic design loads, California engineers are opposed to those from other parts of the country, because if the real severity of earthquakes were recognized in the design loads, there would be no high-rises in San Francisco, or they would be too expensive to be feasible.
21
If you are a tort attorney just sit back and decide what you will do with your hundreds of millions in fees you will collect after the big one hits.
2
“Buildings falling on top of other buildings — that’s not going to happen,” Mr. Klemencic said.
Famous last words. Pretty sure this means that is exactly what is going to happen.
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Check THIS out:
http://www.laweekly.com/news/welds-apart-2130465
3
I lived in San Francisco in the 80s. Worked for MCI at the time. Used to install and repair switches all up and down the state. At the time we thought that bolting those heavy devices to the floor would suffice. (ABAG/Code) told us this would be enough. It would not. There will be another catastrophic earthquake and it will cost billions to rebuild...
12
This is hubris, building these high rises on sand and clay in earthquake zones. I wonder if any of the architects, buildings or people who approved these buildings live in them. Somehow I doubt it. Already you can see, from the slanting sinking building, that the area is not safe, yet if and when the "big one" strikes San Francisco, they'll say "who knew." The amount of money they make on these buildings make it easy for them not to know or acknowledge the imminent dangers. Even with the severe housing shortage in San Francisco, there is no excuse for quite possibly putting the lives of so many people at risk.
42
This story mixes up 2, mostly unrelated, problems. The geotechnical (soil) engineering failure at Millennium Tower and the structural engineering (above the soil) design of tall buildings. In most circumstances, tall buildings are subject to greater shear forces during a hurricane than an earthquake.
The very damaging "s" waves of earthquakes (the force of the wave moving perpendicular to the direction of the wave) are more often a greater threat to long structures than tall ones (thus the need to reinforce highways, bridges, tunnels; Home Depots and Costcos).
Building tall buildings for "functional recovery" after a once in a 1000 year earthquake would make many structures cost prohibitive to build. Just like with flooding across the world, buildings and communities are designed to deal with once per 100-year floods; sometimes once per 500-year floods. I don't see why we would look at earthquake design any differently.
31
Let's be clear: winds/hurricanes primarilly affect a structure ABOVE ground level. Earthquakes' primary effect on a structure is via the foundation and if the surrounding soil conditions get squishy and a highrise structure is not tied down to bedrock - you're telling us there'd be no problem in a major event - an event that would last more than a minute. Northridege '94 lasted only twenty seconds. You seem to infer that MASSIVE liquifaction in a major event would not threaten Millennium Tower. ???
4
"Now retired, Mr. Macris said the issue of seismic safety of high rises was “never a factor” in the redevelopment plans of the South of Market area, or SoMa, as it’s known."
How can this be? I am dumbfounded to read that statement.
107
Earthquakes around San Francisco have occurred before and are likely to recur...although no dates have been set by nature (plate movements beneath Earth surface). One would think that we have strict codes to control Earthquake's sudden vibration instability on high or low rise buildings. Look at Chile, and the destruction and chaos derived from their 2010 Earthquake, partly a result of relaxing discipline in enforcing the existent codes. Be this a lesson for S.F., if it thinks it can save some money, or make a profit, by looking the other way, a shortsighted view pregnant with danger.
Here's to hoping the vanity of out-of-town designers and their larger-than-life clients does not result in a completely avoidable loss of life.
5
As a 4th generation San Franciscan, all I can say is that the big money boys, as usual, got what they wanted, aided by architects and engineers with incredible nerve. They're all making a pile of dough putting up those high rises and they will most likely be long gone when the big one hits and levels the city of San Francisco again.
What's the definition of insanity again? Something about doing the same thing over and over and expecting a different result?
99
And it appears that no amount of "shock treatment" will result in sanity. The gods are having a wonderful time watching the Umptieth Season of "We're in Charge, Clueless and Nobody Can Stop Us".
2
Good article. It's hard for the public to understand the uncertainties in quake forecasting, how difficult it is to precisely quantify risks & to understand the challenges of trying to engineer earthquake resistant structures.
Most people understand that California is at risk because of the San Andreas Fault. This "fault" is really a highly complex fault system consisting of a number of parallel faults & numerous branching faults. The knowledge to predict what will happen on any branch is limited to probability estimates.
To get a sense of this system around the Bay area see a simplified diagram here (it's equally complex in the LA area):
https://pubs.usgs.gov/fs/2016/3020/fs20163020.pdf
Based on past seismic events, stress monitors and other data, the Hayward and San Andreas Branches are the most likely to rupture and generate a large quake over the next 30 or so years.
What the public doesn't realize is that you can't just tell design engineers to build something that will withstand any quake. We don't have the technology today to do that, at least not that is affordable.
Today, engineers can use isolation devices, tuned dampers, box construction etc to lesson damage, but the crucial fact is that if the epicenter/focus of a large quake (mag 7 or 8) is under downtown SF, few buildings there today will survive. Much depends on how far away the epicenter is.
Building codes need to be as robust as possible, but if a really big one hits, hope you are out of town that day.
84
How safe is safe enough...?
This is a societal question that is difficult to answer...and scientists/engineers cannot quantify it in a meaningful way (e.g., do a calculation to determine the "right" amount of seismic protection). This is why building codes are largely experienced-based, that is, significant changes to the building code are usually made after damaging earthquakes when the public perception necessitates actions.
The soft-story building upgrade program mentioned in the article was the outcome of damage observed during the 1989 Loma Prieta earthquake that damaged these types of buildings. Likewise, for the brittle steel connection issue also mention in article that was discovered after the 1994 Northridge earthquake affecting highrise buildings in Los Angeles.
Hence, I do not expect major changes to the building code until after an earthquake damages highrise buildings.
1
Yes, scientists and engineers can quantify acceptable risk in a meaningful way, using well established scholarly tools. A number of the social sciences have treated public preferences rigorously for decades. These disciplines include communication, computer science, economics, journalism, political science, public health, public relations, psychology, sociology, statistics, and survey methodology. A few recent engineering studies have actually rigorously elicited public preferences for tradeoffs between cost and seismic performance. Engineers have actually done calculations to determine the right amount of seismic protection. If there are no changes to the building code until after an earthquake damages highrise buildings, it may only be because engineers and the building trades refuse to use the tools at hand or reject or ignore the products of those tools.
1
Apart from a few zoning laws, cities in the US suffer in general from a lack of planning. Basically developers and the market defined what gets built and how, and city councils are no match for professional developers and the relentless pressure they impose. If we're lucky the big one won't come for 1000 years and we will have successfully pushed the problem down the road.
4
South-of-Market will be underwater 1000 years from now, even without any earthquakes. That is pretty certain.
3
1000 years? Not likely. Earthquake recurrence studies suggest major events every century or so.
And for every "big one", nature provides at least 10 "big enough" quakes, the kind that can kill only a few hundred people and cause only a few billion in damage.
3
The age of denial travels up the coast into Canada. Read this Pulitzer Prize winning New Yorker article on the Really Big One....the Cascadia fault that runs from Medocino to Vancouver Island. Its potential magnitude is over 9.2 and...it is overdue. Are we ready? Nope..still building on high risk.
https://www.newyorker.com/magazine/2015/07/20/the-really-big-one
2
It’s astounding to me that more in-depth thought wasn’t put into this ahead of time. The first thing I thought when they started building in this area was “they’re building on sand and fill… I hope they know what they’re doing.” I assume a lot of other people who grew up in the Bay Area thought the same thing. It can be extraordinarily difficult to build new housing in San Francisco, sometimes because of relatively trivial objections made by some residents that don’t want new housing of practically any sort, but when it comes to earthquake safety we truly do need to err on the side of extreme caution.
59
I asked that question, too, and was assured that the foundations were on pilings that had been driven hundreds and hundreds of feet into the ground, so everything would be fine. I doubt that, but very few city officials, elected or otherwise, can resist when the really big money comes calling. Having lived through the Napa quake--yay for wooden houses--I worry about San Francisco.
16
"The farther away the future is, the better it looks."
―Finnigan's Law
2
"I hope they know what they're doing."
Building codes are MINIMUM standards, the lowest acceptable standard. Everyone can build better than code if they choose to.
Good engineers know very well what they're doing. But building codes come about through a process that involves engineers, builders, developers and code officials. They all have their say.
Typically the builders and developers argue for looser codes, to reduce building costs. Engineers argue for tighter codes to reduce liability risk.
Once the codes are made, if the developers win out, the engineers are stuck with it. If they want to work they have to design to the code minimum. Most developers are interested 100% in the bottom line, short term gain. So they demand that the design be done to the minimum.
In the case of highrises it's my view that friction piles should be banned in most of downtown and only end bearing piles be allowed. But that would cost more. So the developers resist it. As they see it, there's no payback on money spent for a more reliable foundation system.
1
Yes, building and living in San Francisco present exceptional hazards, that Fuller, Singhvi, and Williams accurately describe but perhaps minimize. A large enough earthquake, at the "wrong" time, has the potential to kill tens of thousands, injure many more, and devastate emergency services and other immediate response resources. As they describe, many buildings that do not collapse will be damaged beyond repair. Building codes focus on maintaining enough structural integrity so that people can escape, not necessarily for the preservation of the building itself.
Beyond the immediate devastation, the cost of "rebuilding" would be unimaginable, as would the challenge of feeding and housing a million displaced people.
Geologic process cannot be denied. To get a better appreciation for the occurrence of earthquakes in the area, do an internet search for seismicity maps, or visit the USGS website https://earthquake.usgs.gov/earthquakes/map/
By changing the map settings you can see earthquakes of various magnitudes, including all earthquakes for the past 30 days (lots!), and zoom to the Bay Area.
6
There goes the neighborhood.
12
The cost of housing issue is nonsense. There are two components of housing cost: Structure and land. The demand curve for housing does not change. When you increase the cost of the structure the land becomes less valuable. The same is true in flood plains. What is hidden is the "risk cost" the risk makes the structure less valuable by roughly what it costs to insure it fully. Lousy buildings reward land speculators.
5
50 years ago while stuck in traffic stop a spindle freeway support in San Francisco, I pondered my demise if the "big one" struck then! It didn't. Different city today but same question? When?
9
I remember a documentary from high school Geology: "The City that Waits to Die." Great town, but I can barely bring myself to visit.
7
San Francisco is a great city, and will always be! We wish them the best. I guess, however, there's nothing like Manhattan, Brooklyn, and the Bronx, bedrock! Now, if they can just fix the subways and potholes!
30
Don't be so complacent; New York City sits on numerous fault lines, not to mention the one that goes directly under the Indian Point Nuclear Power plant a few miles up the river.
25
Hi Counter Measures, uh....you have a small problem with Sea Level Rise to confront in Manhattan, and certainly parts of Brooklyn and the Bronx. I guess we should modify the “those in glass houses” saying to be “those in low-lying houses”. Granted we have the double whammy of planning for seismic and climate risks in SF....
https://www.nytimes.com/interactive/2018/04/17/us/san-francisco-earthqua...®ion=top-news&WT.nav=top-news
2
Yes, bedrock, but don't forget sea level rise and hurricanes named Andrew. We wish you the best too.
3