Too Late To Evacuate New York City (Revelation 6)

Is It Time to Move Our Cities? | The Tyee

The end of this wretched summer will go unlamented by all North Americans: raging wildfires from B.C. to California, no fewer than three catastrophic hurricanes (so far), and two disastrous earthquakes in southern and central Mexico.
Having grown up in Mexico City when it was a sleepy pueblo of just three million under clear blue skies, I’ve taken its latest earthquake very personally. I went through a couple of minor quakes there, and a big one in July 1957. Even then, everyone knew the Valley of Mexico was a terrible place to build even a pueblo, let alone a huge national capital.
Much of the valley used to be a lake, and the Aztec capital Tenochtitlán was built on islands in it. The conquering Spaniards drained the lake looking for treasure (no luck), and then built a new city on the lake bed. The water kept seeping back. I recall a huge excavation across the street from our house, the intended foundation of a large building; it was a vast rectangular lake, supporting billions of mosquitos.
Downtown, the Palace of Fine Arts had been started circa 1910; it sank into the lake bed, and wasn’t finished until the 1930s. In the 1950s, you had to go down a long flight of stairs from street level to enter it.
Mexico City’s spongy soil, like the Fraser Delta’s, tends to liquefy in severe earthquakes. That made the quakes of 1957 and 1985 notably bad, and led to tougher building codes. But corruption, like love, will always find a way, and almost 50 buildings collapsed in the Sept. 19 quake. Hundreds more will have to be abandoned and demolished.
The quake brought out the very best in the Mexican national character, with neighbours struggling to rescue neighbours. But it’s been a struggle they should not have had to make.
Move Mexico City?
That thought sank in with me when I read a comment on a New York Times report about the quake. The commenter was Jonathan Katz, who was a reporter in Port-au-Prince when the 2010 Haitian earthquake hit, and who stayed on to report the cholera outbreak. He also wrote a superb book about the disasters and our response, which only made them worse.
Katz suggested that the government: “... gradually move Mexico City to somewhere else in Mexico. Mexico City sits on a dried lake bed, terrible seismically because it amplifies earth movements. Buildings also settle (in some cases by a whole storey) and it's in a basin that traps air pollution. Plan a new city on a ridge (good bedrock, fresh breezes) not too far away, and gradually move government offices there. The rest of the city will follow, especially if new building in the old Mexico City is forbidden by zoning.
“Costa Rica did something like this after Cartago was largely destroyed by an earthquake. The capital is now San Jose.”
That’s not the only example Katz could have cited. The capital of colonial Guatemala, now known as Antigua, suffered repeated earthquakes until the capital was moved to what is now Guatemala City. Brazil moved its capital in the early 1960s from Rio de Janeiro to Brasilia simply to move both population and national attention away from the coast and into the country’s vast interior. For that matter, Washington, D.C. was a politically chosen capital for the U.S., as was Ottawa.
So Katz’s idea isn’t entirely farfetched. Granted, 21.3 million Mexico City residents aren’t likely to pack up their belongings and move next week. But that population has grown sevenfold since the 1950s because the city was where the money and jobs were. Move the money and jobs elsewhere, and the people will follow.
Megathrust quakes and tsunamis
Those of us on the coasts of North America might start seriously thinking about relocation as well — especially here in B.C. We have focused most of our population in the southwest corner of the province. That’s like most of the population of California, Oregon, Idaho and Washington state choosing to live in San Diego. Our choice has put us at risk of earthquakes, tsunamis, wildfires and floods.
We might therefore begin to think where to house ourselves (and likely millions of refugees from the south) in places that would be somewhat safer and more sustainable.
It wouldn’t be easy. Geologically, our whole province is a multi-vehicle crash site of ancient island chains piled up against the Rocky Mountains. We’ll always have earthquakes, large and small.
But we might find some good sites in the Cariboo or Chilcotin. By “mining” our existing coastal cities, we could build new cities relatively cheaply before the coasts go under water. Dams on the Fraser, Skeena and other rivers could preserve glacier meltwater otherwise lost to the rising sea. Genetic engineering could help develop new forests resistant to drought, fire and beetles.
It may seem like a bizarre proposal, but history and prehistory are full of civilizations that stayed put and disappeared, like the Mound Builders of the American Middle West. Over 3,000 years ago, a flourishing civilization in the eastern Mediterranean collapsed under the impact of climate change and invasions.
Other societies moved and changed. The Maya recurrently abandoned their great cities (and their overlords) and went back to small-village farming when serious drought ruined the corn harvests. In New Mexico, the “great house” civilization of the Anasazi deserted its old sites in an 11th-century drought and built a new society — after a dark age of violence and starvation.
We know why those civilizations changed or died, but if we think we’re somehow smarter than they were, we’re the greater fools. We should try to learn from their fate, and act accordingly. Whatever the short-term cost, we might just manage to survive the worst time in humanity’s 300,000-year history. That time has already begun. [Tyee]

Real Risk, Few Precautions for the Sixth Seal in NYC (Revelation 6:12)

        By WILLIAM K. STEVENS

Published: October 24, 1989
AN EARTHQUAKE as powerful as the one that struck northern California last week could occur almost anywhere along the East Coast, experts say. And if it did, it would probably cause far more destruction than the West Coast quake.
The chances of such an occurrence are much less in the East than on the West Coast. Geologic stresses in the East build up only a hundredth to a thousandth as fast as in California, and this means that big Eastern quakes are far less frequent. Scientists do not really know what the interval between them might be, nor are the deeper-lying geologic faults that cause them as accessible to study. So seismologists are at a loss to predict when or where they will strike.
But they do know that a temblor with a magnitude estimated at 7 on the Richter scale – about the same magnitude as last week’s California quake – devastated Charleston, S.C., in 1886. And after more than a decade of study, they also know that geologic structures similar to those that caused the Charleston quake exist all along the Eastern Seaboard.
For this reason, ”we can’t preclude that a Charleston-sized earthquake might occur anywhere along the East Coast,” said David Russ, the assistant chief geologist of the United States Geological Survey in Reston, Va. ”It could occur in Washington. It could occur in New York.”
If that happens, many experts agree, the impact will probably be much greater than in California.Easterners, unlike Californians, have paid very little attention to making buildings and other structures earthquake-proof or earthquake-resistant. ”We don’t have that mentality here on the East Coast,” said Robert Silman, a New York structural engineer whose firm has worked on 3,800 buildings in the metropolitan area.
Moreover, buildings, highways, bridges, water and sewer systems and communications networks in the East are all older than in the West and consequently more vulnerable to damage. Even under normal conditions, for instance, water mains routinely rupture in New York City.
The result, said Dr. John Ebel, a geophysicist who is the assistant director of Boston College’s Weston Observatory, is that damage in the East would probably be more widespread, more people could be hurt and killed, depending on circumstances like time of day, and ”it would probably take a lot longer to get these cities back to useful operating levels.”
On top of this, scientists say, an earthquake in the East can shake an area 100 times larger than a quake of the same magnitude in California. This is because the earth’s crust is older, colder and more brittle in the East and tends to transmit seismic energy more efficiently. ”If you had a magnitude 7 earthquake and you put it halfway between New York City and Boston,” Dr. Ebel said, ”you would have the potential of doing damage in both places,” not to mention cities like Hartford and Providence.
Few studies have been done of Eastern cities’ vulnerability to earthquakes. But one, published last June in The Annals of the New York Academy of Sciences, calculated the effects on New York City of a magnitude 6 earthquake. That is one-tenth the magnitude of last week’s California quake, but about the same as the Whittier, Calif., quake two years ago.
The study found that such an earthquake centered 17 miles southeast of City Hall, off Rockaway Beach, would cause $11 billion in damage to buildings and start 130 fires. By comparison, preliminary estimates place the damage in last week’s California disaster at $4 billion to $10 billion. If the quake’s epicenter were 11 miles southeast of City Hall, the study found, there would be about $18 billion in damage; if 5 miles, about $25 billion.
No estimates on injuries or loss of life were made. But a magnitude 6 earthquake ”would probably be a disaster unparalleled in New York history,” wrote the authors of the study, Charles Scawthorn and Stephen K. Harris of EQE Engineering in San Francisco.
The study was financed by the National Center for Earthquake Engineering Research at the State University of New York at Buffalo. The research and education center, supported by the National Science Foundation and New York State, was established in 1986 to help reduce damage and loss of life from earthquakes.
The study’s postulated epicenter of 17 miles southeast of City Hall was the location of the strongest quake to strike New York since it has been settled, a magnitude 5 temblor on Aug. 10, 1884. That 1884 quake rattled bottles and crockery in Manhattan and frightened New Yorkers, but caused little damage. Seismologists say a quake of that order is likely to occur within 50 miles of New York City every 300 years. Quakes of magnitude 5 are not rare in the East. The major earthquake zone in the eastern half of the country is the central Mississippi Valley, where a huge underground rift causes frequent geologic dislocations and small temblors. The most powerful quake ever known to strike the United States occurred at New Madrid, Mo., in 1812. It was later estimated at magnitude 8.7 and was one of three quakes to strike that area in 1811-12, all of them stronger than magnitude 8. They were felt as far away as Washington, where they rattled chandeliers, Boston and Quebec.
Because the New Madrid rift is so active, it has been well studied, and scientists have been able to come up with predictions for the central Mississippi valley, which includes St. Louis and Memphis. According to Dr. Russ, there is a 40 to 63 percent chance that a quake of magnitude 6 will strike that area between now and the year 2000, and an 86 to 97 percent chance that it will do so by 2035. The Federal geologists say there is a 1 percent chance or less of a quake greater than magnitude 7 by 2000, and a 4 percent chance or less by 2035.
Elsewhere in the East, scientists are limited in their knowledge of probabilities partly because faults that could cause big earthquakes are buried deeper in the earth’s crust. In contrast to California, where the boundary between two major tectonic plates creates the San Andreas and related faults, the eastern United States lies in the middle of a major tectonic plate. Its faults are far less obvious, their activity far more subtle, and their slippage far slower. 
Any large earthquake would be ”vastly more serious” in the older cities of the East than in California,  said Dr. Tsu T. Soong, a professor of civil engineering at the State University of New York at Buffalo who is a researcher in earthquake-mitigation technology at the National Center for Earthquake Engineering Research. First, he said, many buildings are simply older, and therefore weaker and more  vulnerable to collapse. Second, there is no seismic construction code in most of the East as there is in California, where such codes have been in place for decades.
The vulnerability is evident in many ways. ”I’m sitting here looking out my window,” said Mr. Silman, the structural engineer in New York, ”and I see a bunch of water tanks all over the place” on rooftops. ”They are not anchored down at all, and it’s very possible they would fall in an earthquake.”
 Many brownstones, he said, constructed as they are of unreinforced masonry walls with wood joists between, ”would just go like a house of cards.” Unreinforced masonry, in fact, is the single most vulnerable structure, engineers say. Such buildings are abundant, even predominant, in many older cities. The Scawthorn-Harris study reviewed inventories of all buildings in Manhattan as of 1972 and found that 28,884, or more than half, were built of unreinforced masonry. Of those, 23,064 were three to five stories high.
Buildings of reinforced masonry, reinforced concrete and steel would hold up much better, engineers say, and wooden structures are considered intrinsically tough in ordinary circumstances. The best performers, they say, would probably be skyscrapers built in the last 20 years. As Mr. Silman explained, they have been built to withstand high winds, and the same structural features that enable them to do so also help them resist an earthquake’s force. But even these new towers have not been provided with the seismic protections required in California and so are more vulnerable than similar structures on the West Coast.
Buildings in New York are not generally constructed with such seismic protections as base-isolated structures, in which the building is allowed to shift with the ground movement; or with flexible frames that absorb and distribute energy through columns and beams so that floors can flex from side to side, or with reinforced frames that help resist distortion.
”If you’re trying to make a building ductile – able to absorb energy – we’re not geared to think that way,” said Mr. Silman.
New York buildings also contain a lot of decorative stonework, which can be dislodged and turned into lethal missiles by an earthquake. In California, building codes strictly regulate such architectural details.
Manhattan does, however, have at least one mitigating factor: ”We are blessed with this bedrock island,” said Mr. Silman. ”That should work to our benefit; we don’t have shifting soils. But there are plenty of places that are problem areas, particularly the shoreline areas,” where landfills make the ground soft and unstable.
As scientists have learned more about geologic faults in the Northeast, the nation’s uniform building code – the basic, minimum code followed throughout the country – has been revised accordingly. Until recently, the code required newly constructed buildings in New York City to withstand at least 19 percent of the side-to-side seismic force that a comparable building in the seismically active areas of California must handle. Now the threshold has been raised to 25 percent.
New York City, for the first time, is moving to adopt seismic standards as part of its own building code. Local and state building codes can and do go beyond the national code. Charles M. Smith Jr., the city Building Commissioner, last spring formed a committee of scientists, engineers, architects and government officials to recommend the changes.
”They all agree that New York City should anticipate an earthquake,” Mr. Smith said. As to how big an earthquake, ”I don’t think anybody would bet on a magnitude greater than 6.5,” he said. ”I don’t know,” he added, ”that our committee will go so far as to acknowledge” the damage levels in the Scawthorn-Harris study, characterizing it as ”not without controversy.”
For the most part, neither New York nor any other Eastern city has done a detailed survey of just how individual buildings and other structures would be affected, and how or whether to modify them.
”The thing I think is needed in the East is a program to investigate all the bridges” to see how they would stand up to various magnitudes of earthquake,” said Bill Geyer, the executive vice president of the New York engineering firm of Steinman, Boynton, Gronquist and Birdsall, which is rehabilitating the cable on the Williamsburg Bridge. ”No one has gone through and done any analysis of the existing bridges.”
In general, he said, the large suspension bridges, by their nature, ”are not susceptible to the magnitude of earthquake you’d expect in the East.” But the approaches and side spans of some of them might be, he said, and only a bridge-by-bridge analysis would tell. Nor, experts say, are some elevated highways in New York designed with the flexibility and ability to accommodate motion that would enable them to withstand a big temblor.
Tunnels Vulnerable
The underground tunnels that carry travelers under the rivers into Manhattan, those that contain the subways and those that carry water, sewers and natural gas would all be vulnerable to rupture, engineers say. The Lincoln, Holland, PATH and Amtrak tunnels, for instance, go from bedrock in Manhattan to soft soil under the Hudson River to bedrock again in New Jersey, said Mark Carter, a partner in Raamot Associates, geotechnical engineers specializing in soils and foundations.
Likewise, he said, subway tunnels between Manhattan and Queens go from hard rock to soft soil to hard rock on Roosevelt Island, to soft soil again and back to rock. The boundaries between soft soil and rock are points of weakness, he said.
”These structures are old,” he said, ”and as far as I know they have not been designed for earthquake loadings.”
Even if it is possible to survey all major buildings and facilities to determine what corrections can be made, cities like New York would then face a major decision: Is it worth spending the money to modify buildings and other structures to cope with a quake that might or might not come in 100, or 200 300 years or more?
”That is a classical problem” in risk-benefit analysis, said Dr. George Lee, the acting director of the Earthquake Engineering Research Center in Buffalo. As more is learned about Eastern earthquakes, he said, it should become ”possible to talk about decision-making.” But for now, he said, ”I think it’s premature for us to consider that question.”