On Shaky Ground

by Nance, John J. ;

  But the Mexican capital was a city of more than one million buildings and eighteen million people. Most of Mexico City still stood intact. Unreinforced masonry buildings in the areas of worst shaking had all but exploded, and some reinforced concrete towers standing too close to other similar buildings ended up beating each other to pieces, but older structures such as the Metropolitan Cathedral and very modern skyscrapers, such as the fifty-two-story headquarters of Pemex (the Mexican state oil company and the tallest building in Latin America), still stood effectively undamaged. Even Mexico City’s airport, located entirely on the old lake bed, had come through intact. While it was a horrendous tragedy—while the price in human lives and human suffering would stagger the imagination—it was obvious even in the early stages of recovery that the seismic building codes had worked to save lives and property.

  It was also obvious, Karen knew, that the monstrous destruction which had occurred over 230 miles from the epicenter of the coastal quake validated what Dr. Otto Nuttli of St. Louis University had been warning of for so long regarding the East Coast of the United States: Great earthquakes could cause massive damage hundreds of miles away. The New Madrid Fault, for instance, could collapse buildings in Chicago and Kansas City, Dallas, Little Rock, New Orleans, and Memphis all in the same cataclysm if it produced a future Ms 8.0 or greater earthquake. Many seismologists and seismic engineers had winked indulgently at Nuttli’s theoretical worries in past years. Now, of course, they would have to take him more seriously. If Mexico City produced no other lessons, it would drive that one home.

  As Karen began braking the Travelall to a halt to drop the first seismograph, 210 miles to the east in Mexico City Dr. José Cruz had felt his heart nearly stop as he recognized the words in Spanish from a rescuer somewhere in the darkness above him:

  “Demasiado personas son muerte ahora, un otro no está importante. [Many people are already dead, (if another dies) it doesn’t matter].”

  The chief of a rescue squad which had been trying for hours to tunnel through to him had been told to give up. But they had argued vehemently and successfully for more time. Now the time was gone, the rescuers were many steel rods and concrete chunks away from where Dr. Cruz had been imprisoned, and once again they were being told to give him up for dead and move on.

  José Cruz had heard the sounds of other people being pulled joyously into the sunlight in the previous hours, escaping the prison that the pancaked floors of the hospital had become. He had longed to join them—he had yelled and screamed for help until hoarse—but now he would surely die.

  An argument flared outside, the boss relented again, and once more the digging began—one of a thousand Herculean efforts across the damaged city.

  And once more the young doctor had a chance.

  On Monday morning, while Karen McNally slept through the last few minutes of a short night on the Michoacán coast, Dr. José Cruz was finally pulled into the morning light, bruised, dehydrated, emaciated, traumatized, and shaking—but alive, two days past his twenty-third birthday. Behind him, however, in the rubble, were over five hundred patients and doctors and nurses who had not been so fortunate. Even as Cruz was being loaded into an ambulance before waiting TV cameras, those trapped within tried to hold on still longer, clinging to a last few hours of life while frustrated rescuers practiced the art of the possible.

  And as Karen McNally and her team punched off portable alarm clocks and prepared for another exhausting day of tending remote portable seismographs along the coast, the knowledge that the Michoacán seismic gap had been filled by the great quake was replaced by the more ominous reality that the Guerrero gap—adjacent to Acapulco and right between the site of the Oaxaca quake and the Michoacán (Mexico City) quake—was next. The seismic gap method obviously worked in providing the answers to whether and where—the only remaining question was when. And answering that one would take a lot more time, and a lot more research—the financing for which would ultimately have to come from the Congress of the United States.

  Washington, D.C.—Thursday, October 3, 1985

  Senator Slade Gorton of Washington State took his seat at the head of the hearing table in the second-floor room of the Russell Senate Office Building, aware that as he prepared to gavel the proceedings into session, the cleanup continued nearly two thousand miles distant in Mexico City. The official death toll was above five thousand now, the unofficial toll over ten thousand, and damages were being estimated in the range of four to five billion dollars. Gorton’s subcommittee (on Science, Technology, and Space) of the Senate Committee on Commerce, Science, and Transportation had hurriedly asked a group of distinguished scientists and professors to come to Washington to begin building a graphic record on exactly what had occurred in the Mexican capital. To Gorton and the only other senator present, Al Gore of Tennessee, the exercise was urgent and very important.

  Slade Gorton, a tall and distinguished-looking lawyer and former Washington State attorney general, was well aware that his own home state of Washington was earthquake country. Thus the subject was doubly important to him, especially since there had been indications lately that Washington, Oregon, and Northern California might be subject to the same magnitude of great subduction zone earthquake which had just occurred in Michoacán.

  The previous March, Gorton had dealt with the reauthorization of the Earthquake Hazard Reduction Act, which President Reagan had just signed. That had helped open his eyes to the problem, but Mexico City had ushered in a higher magnitude of sensitivity. There were obviously profound lessons the United States needed to learn from this great earthquake, and perhaps this early hearing record would be a beginning.

  Slade Gorton noticed the clock standing at 10:25 A.M., the appointed time for the hearing, as he looked at the different people now taking their seats. Representatives from the Federal Insurance Administration, the Federal Emergency Management Agency, and the USGS were off to one side, along with a friend of Senator Gore’s, Dr. Arch Johnston, director of the Tennessee Earthquake Information Center in Memphis, and a professor at Memphis State. Johnston had been almost alone for many years in his attempts to alert his hometown to the fact that the New Madrid Fault could bring the city of Memphis to its knees in any future great quake. He was making progress, but it was slow going.

  And near Dr. Johnston was a familiar face from Gorton’s home state, Dr. Linda Noson, a seismologist from the University of Washington in Seattle who also served as the state seismologist in an even lonelier quest to alert Washingtonians about the dangers of future earthquakes.

  Gorton banged his gavel and began, making a brief opening statement before turning the floor over to Al Gore.

  “Two weeks ago today,” Senator Gore began, “the world witnessed one of the worst natural disasters of recent years. On September 19, an earthquake registering 8.1 on the [surface magnitude] scale struck the western coast of Mexico.…

  “The tragedy of Mexico City’s earthquake illustrates all too starkly the devastation that can result when a city is prepared to cope with neither the eventuality of an earthquake nor the tremendous damage that can be caused by one.

  “Indeed, the city lay vulnerable to the earthquake that struck it like a sad, helpless giant. Many of the buildings were structurally incapable of withstanding an earthquake, and the ground upon which [a portion of] the city stands actually amplified the shock-waves.

  “Even worse, once the disaster had occurred, the city proved incapable of responding quickly to the disaster.…

  “There are many lessons that we in the United States should learn from the earthquake.… [F]oremost among these is that we must do everything within our ability to assure that no city or area in this country suffers like Mexico City because of an earthquake. We must take every step to make certain we are prepared for the eventuality of earthquakes, and that we are capable of responding swiftly and effectively to them when they occur.

  “Earthquakes are not a possibility,” Gore continued. “They are a c
ertainty.…”

  Nevertheless, as the hearing progressed, the specter of a legislative measure known as the Gramm-Rudman-Hollings amendment continued to spread its inexorable shadow over the federal budget, threatening even the newly reauthorized Earthquake Hazard Reduction Act, and threatening to reduce, rather than expand, the lifeline of federal funding which had already dried to a trickle for far too many university researchers, such as Dr. Karen McNally, who depend on federal grants through the USGS to keep going.3 Funds for other vital programs—efforts such as Dr. Arch Johnston’s Earthquake Information Center activities in Memphis—were also tight to nonexistent. It was obvious to many in the hearing room that until the issue became a sufficiently significant national priority—until people realized that not only Los Angeles, but Memphis, St. Louis, Chicago, Buffalo, or even New York City could be transmitting those horrific television images of crushed humanity and destroyed lives—the momentum and the money would remain ridiculously insufficient.

  Chapter 22

  Charleston, South Carolina—1987

  The last of the tourists—a man and a woman walking arm in arm—moved silently past the imposing gazebo of the elegant old waterfront park, seemingly lost in their enjoyment of the lyrical setting under the starlit canopy of a South Carolina summer night.

  The south side of the park called White Point Gardens was bordered by Murray Boulevard at the southern point of old Charleston—overlooking the confluence of the Ashley and Cooper rivers and the lights of historic Fort Sumter farther south toward the Atlantic.

  The north side, however, held a wall of American poetry in brick and mortar on the other side of South Battery, a picturesque street adorned with expensive, historic residences rich in American history and the tapestry of life in nineteenth-century South Carolina—and rich with the promise of instant disaster if what happened beneath the alluvial muds of Charleston in 1886 were to occur again.

  “It’s the same old story,” the Charleston city engineer had said. “Mortar reduced to virtually nothing but sand and powder. As long as nothing moves it, it’s all right.”

  Charleston had been warned for most of the summer of 1886, but no one really knew what the warning meant. Residents of the elegant American city had heard constant tales about swarms of small earthquakes occurring just to the north of Charleston in the farming community of Summerville, but few paid any attention. There was no one in 1886 who had any reason to suspect that what the Low Country (as the Charleston area was called) had felt might be the low-volume overture to an impending symphony of seismic waves.

  At 9:51 P.M. on the 31st of August, however, an unseen and unknown fault somewhere beneath the thousands of feet of sediments underlying Charleston rumbled into motion, great rock faces suddenly moving past each other, breaking whatever snag had been holding back a torrent of stored energy. The city shuddered with the first P wave arrivals, then began to whip and shake horrendously in the grip of what would be identified decades later as probably a surface magnitude Ms 7.7 earthquake. For thirty-five to forty seconds the ground beneath the city (an alluvial aggregate thoroughly saturated with water) lurched first to one side, then to the other, the multistory brittle, unreinforced masonry buildings trying to follow their foundations, but fragmenting into a million flying pieces amidst dust and falling timbers. Stucco, masonry blocks, and bricks were presumed glued together by mortar, but the high-lime mortar had turned to sand over the years, leaving much of Charleston’s elegant brick buildings intact only through the grace of gravity and the audacity of weight.

  Now in the grip of a great quake, they began collapsing like an unsupported wall of canned goods in a grocery store, fourteen thousand chimneys crumbling, walls and entire houses fragmenting and falling on a population which would lose sixty lives and hundreds of destroyed homes to the deadly rain of ruined building materials. As the worst of the shaking took hold of Charleston, a spherical wave of seismic energy fanned out to neighboring communities, spreading like the ripples from a rock thrown in the middle of a quiet pond, wreaking havoc and shaking apart man-made structures as far away as a hundred miles.

  And what the main shock didn’t disintegrate, a hard aftershock eight minutes later would finish off.

  Charleston lay badly damaged, with over twenty-three million dollars in destruction. And Charleston’s population, both black and white, was traumatized. As aftershocks continued, people moved onto lawns and common areas, some vacating perfectly sound houses for weeks in fear. Prayer meetings became thoroughly interracial as a shocked community of fellow humans shuddered at their vulnerability in the face of such power.

  But as has been American tradition since the earliest days, Charleston dove into the task of rebuilding itself. Within a year the city’s reconstruction effort had reached significant milestones—not the least of which was an inadvertent legacy of vulnerability to future great quakes: many seriously weakened buildings were rebuilt with little more than cosmetic patching.1

  Most of the homes which had been standing in 1886 had suffered major damage, but the majority were repaired too superficially, with grave structural weaknesses hidden beneath a veneer of fresh mortar. Now they sat in endless ranks, these elegant mansions, looking permanent and timeless, bathed in the soft light of sodium vapor lamps from the southernmost park in the city, sitting like stately ghosts along the margin of the treelined South Battery Street in the cool, humid breeze blowing up the bay from the direction of Fort Sumter, mansions at once elegant and imposing and dangerous as hell.

  How do you get people to rebuild fantastically expensive old classics like those? The question had haunted seismically knowledgeable engineers for years. And in other American cities thousands of buildings which had little or no historical value and were verified seismic bombs remained standing with the same financial momentum. Passing new, stringent seismic building codes and requiring new buildings to conform is many times easier than forcing people to tear down or completely rebuild existing structures which may be worth millions.

  Charleston in particular was merely waiting for disaster, the entire southern end—the classic, historic, beautiful section which drew tourists each year by the tens of thousands—barely held together by powdery mortar. In 1981, for instance, the front of one old building at 64 Beaufain Street simply collapsed spontaneously, the stucco and brick cascading down onto the sidewalk in front of startled pedestrians (none of whom was hurt). The collapse prompted Charleston’s chief building official, Doug Smits, to order it vacated—and rebuilt. But the thing that had chilled Smits and many others was the apparent cause of the collapse: mere traffic vibrations.2 The three-story house had been built before the Civil War, and though the great quake of 1886 had not demolished it, the masonry structure apparently had cracked and fragmented in places which remained hidden for the next hundred years behind freshly applied—but structurally useless—masonry veneer.

  “The only thing that held that part of the facade [at 64 Beaufain] together,” Smits had said, “[was] the stucco.”

  There was no easy answer, of course. It had taken Los Angeles sixteen years to rebuild or tear down only a third of its dangerous masonry buildings—their “seismic bombs”—and few, if any, of those had historic value. Charleston was awash in multimillion-dollar structures of considerable historic value which had been significantly weakened in 1886, and which would probably explode into fragments of walls and bricks and chimneys and rubble the next time the unknown fault which had snapped in 1886 lurched again.

  If it was a difficult proposition on the West Coast, it was many times more problematic on the East. The challenge of getting people east of the Rockies to believe a major quake could occur beneath their real estate seemed to bedevil all the experts. Even in Charleston that was true. Even in a city of proven vulnerability where a seismic catastrophe had happened before and so clearly could happen again, people wanted to ignore the possibility.

  Most Charlestonians seemed well aware of their earthquake heritage, but t
hey were equally convinced they had little to worry about in the future.

  “We won’t get another like that for three hundred to a thousand years!” another city official said, “… and most of the dangerous homes won’t last that long anyway without a complete rebuild.”

  Yet there were some valiant efforts under way by some energetic pioneers in earthquake mitigation—people such as Professor Joyce Bagwell of Baptist College at Charleston. An enthusiastic educator, she was one of the first in the nation to attack the problem from the ground up—concentrating her efforts on teaching schoolchildren about earthquakes, involving them in classroom exercises, finding hazards, drawing up lists of repairs, and even making out school requisitions for needed materials.

  “We get them involved,” she explains to visitors; “then they teach their parents.”

  It had been the joint interest of Joyce Bagwell and another Charleston educator, Dr. Charles Lindbergh (a professor of civil engineering at the Citadel), that had prompted them to attend a pivotal conference on eastern earthquake potential held in Knoxville, Tennessee, in 1981. The recognition of just how unprepared their area and the entire eastern seaboard was for major earthquakes had launched both of them into the mainstream of hazard mitigation.3

  Hazard reduction means establishing realistic seismic building codes nationwide—stringent codes based on assessment of potential ground shaking which would require seismic engineering precautions which, on average, would add less than 20 percent to construction costs (even in the most deadly seismic zones such as Charleston, South Carolina, or Redwood City, California). Putting such codes into effect to cover future construction, as well as mandating the teardown or reinforcing of the seismic bombs—the buildings and structures which will unquestionably collapse in a significant earthquake—must become high priorities in New York, Boston, Chicago, St. Louis, Dallas, Kansas City, Louisville, Charleston, and many other cities.