Famous Bridge Failures [1]
In the United States, an average of 128 bridges collapse annually. [2] The most common factor for collapse is hydraulic in nature—what moves underneath the bridge wears it away, produces dangerous gaps in its consistency.
As of 2017, 700 of 14,835 bridges were deemed “structurally deficient” in Georgia, where I live. 1,604 of those bridges are “functionally obsolete.” Despite the $2 billion invested in Georgia bridges from 2005-2014, an estimated $27 billion is needed for all necessary repairs to bring each bridge up to the same standard.
In Illinois, where my father lives, there are more bridges and more problems. 2,407 of the 26,825 bridges are “structurally deficient,” but the cost for repairs is only $5.8 billion. These differences feel important.
In the car on road trips, my sister and I held our breath as we drove over bridges. This wasn’t because we thought about their collapse—like holding your breath passing a graveyard, it was something to do, something everyone did. A test of strength. But perhaps there was some subconscious fear, there. My father’s grip tightening on the steering wheel. A sense that holding our breath was the least we could do to keep ourselves safe, to keep ourselves afloat when we hit what was below.
On our trip to Charleston, we drove the Silas N. Pearman bridge over the Cooper River to Mount Pleasant, holding our breath both as a habit and against the murky smell of the paper factory, looking at the dots of boats in the water beneath us.
To our right was the Grace Memorial bridge, built in 1929, replaced in 1966 by the Pearman bridge. To our left was the Arthur Ravenel Jr. bridge in construction. It was taller, flatter, better, more equipped for the heavy traffic. Instead of the complication of metal joints tangled like a jungle gym the two previous bridges wore, the Ravenel had sleek cables gripping either side and meeting in a confident point. We rode like that, our mouths growing hot and dry from the held air—the past on our right, empty and small, the triumphant future on our left.
The Ravenel would open in 2005, becoming the third longest cable-stayed bridge in the Western Hemisphere and something of a marvel. [3]
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A massive fire broke out under a bridge on the incredibly busy Interstate 85 in Atlanta on March 30th, 2017, causing a 92-foot-long section of the bridge to collapse. Because of the fire, the interstate was closed to traffic and no one was hurt. It was a rare role for fire, to act as both destroyer and rescuer—if it wasn’t there, the bridge wouldn’t have collapsed/if it wasn’t there, people might have died. [4]
They arrested three individuals in connection with the fire, who were later released. Under the bridge was a state-owned storage area containing high-density polyethylene and fiberglass tubing. Under the bridge was a mistake to a criminal degree, the kind of a mistake that, if only for eight months, changes a city. [5]
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Ponte das Barcas was built in Porto, Portugal in 1806. “The Bridge of Boats” consisted of 20 boats standing side-by-side banded together with steel cables. It was built to open for boats passing beneath on the River Duoro; boats parting for boats.
Like all interesting bridge failures, this isn’t just a case of engineering gone wrong, though that’s part of it; like all tragedies, there are causes to trace. In 1792, Queen Maria I of Portugal was declared “mad” [6] by Francis Willis, the same doctor who treated King George III of Great Britain. From the one extant medical report on Maria’s symptoms, doctors think it’s likely the Queen suffered from major depressive disorder brought on, in part, by the deaths of her husband and eldest son. Two out of her three sisters were also “mad,” suffering from similar symptoms. [7] Her son John VI stepped in as Regent in 1792 and was officially confirmed in 1799.
In his new role, John VI made the decision to reopen trade with the British, breaching Napoleon’s Continental Blockade and putting Portugal at risk of invasion. Maria and the entire Braganza Dynasty fled to Brazil in 1807 to establish a government in exile. They made their journey on the Príncipe Real, where Maria’s screams echoed from her cabin—she thought her servants were planning to torture and rob her.
The French first tried to take Lisbon, and failed; on March 29th, 1809, under the leadership of Marshal Soult, they advanced on Porto. Fleeing the horror of Soult’s bayonet charge, citizens of Porto took to the Ponte das Barcas, hoping for safety on the other side of the river. Under the weight of those fleeing, the simple bridge collapsed and 4,000 people lost their lives in the River Duoro.
After the collapse, the bridge was temporarily rebuilt, only to be replaced by a Ponte Pênsil (a suspension bridge) [8] in 1843.
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The Eitai Bridge in Tokyo [9] is a blue steel arch bridge. Arch bridges transfer the weight of the bridge along the curves of the arch, concentrating the force on the supports on each end. These supports are responsible for holding the arch in position; one section fails, the bridge fails. [10]
The Eitai Bridge was the first earthquake-proof structure to be built in Japan after the 1923 Kanto Earthquake of Tokyo-Yokohama. The earthquake caused the iron Eitai Bridge to collapse; although there were no deaths associated directly with the collapse, the earthquake’s death toll was 140,000. [11]
Moving backwards: the iron Eitai Bridge was built to replace the wooden Eitai Bridge, originally built in 1698. The wooden Eitai Bridge collapsed in September 1807, when it was overcrowded during a festival. Supposedly, the bridge had fallen into disrepair, and the two villages on either side couldn’t agree on who was responsible for fixing it. 1,400 people fell into the Sumida river. [12]
A bridge built on a bridge built on a bridge: wood, iron, steel. Covering what needs covered.
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Arthur May Nelson was one of three clowns working for Cooke’s Circus during the summer of 1845. His specialty entrance involved being towed in a washing tub down long waterways by four geese. The trick, of course, was that the tub was actually attached via underwater line to a leading rowboat.
The Yarmouth suspension bridge was built in 1829 and widened in 1832, an expansion which was not supported by the original design. [13]
It was a cloudy afternoon the day the Cooke’s Circus came to Yarmouth. The handbill advertising Nelson’s stunt offered a play on Shakespeare above a somewhat frightening illustration of Nelson in the washtub, equipped with a billowing whip, his expression determined and intense on the four geese in front of him: “’Is it to be a benefit or not?’—that is the question.”
As Nelson floated along, waving at the thousands of viewers watching from the riverbanks and the 300 watching from the southern footway of the bridge, one of the eyebars supporting the bridge failed. A second eyebar on that section of the suspension held the load for about five minutes before it also failed, causing the south side of the deck to dip into the water, tipping the crowd in. The river boiled up against the crowd struggling to resurface. It was reported by a child named Jay that the people under water “looked as if they were hugging each other.” 79 people, many of them children, died. One woman managed to grip her child’s clothes with her teeth to prevent them from being separated in the rushing water and paddle them safely to the shore. [14]
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Ultimate failure strength must be accounted for in any structural design. This means that we must understand what kinds of small failures a structure can take until ultimate failure—how much can go wrong before the bridge finally collapses? The question, then, is not if or even when, but how? How will this bridge finally and inevitably collapse?
A good design accounts for these possibilities in the structural integrity of the item. [15] Like my father and I testing my toothpick bridge with Hot Wheels, you have to know how a structure will hold together under reasonable use.
But there are some types of structural failure you can’t plan for. Manufacturing errors like incorrect sizing or improper heat treating along with the use of defective materials are often unpredictable, difficult to protect against. You can’t know what you don’t know. Perhaps the most frightening type of failure is just that—your inability to anticipate unexpected problems.
These conversations with my father have done little to make me afraid of bridges. Even after the Atlanta collapse, even with my knowledge of how common these failures are, even the catastrophic failures later labeled as disasters, I don’t think about them when I cross bridges. Instead I look over the sides, at the water or the road below, everything marked with an even and reassuring uncertainty. Everything up in the air.
[1] My father was a forensic civil engineer specializing in bridge collapse until he was diagnosed with Delusional Disorder (DD) and lost his job when I was around ten. DD is rare and relatively new; it was first accepted as medical nomenclature in 1987, the year my parents got married, in the DSM-III-R. DD is a psychotic condition with “non-bizarre delusions” like being followed, poisoned, or infected with some disease. This is the key for DD delusions: they could, possibly, in some reality, happen, but they are arrived at with insufficient evidence. They don’t typically stem from hallucinations, but rather a warped interpretation of an experience; a sort of jumping-to-conclusions on a grand scale. Making connections where there are none.
[2] Collapses, among other engineering failures, farming, and Mark Twain, are on my list of safe topics to discuss with my father during our biweekly phone calls. He moved to the Midwest shortly after his diagnosis and rarely visits, so much of our connection happens through these phone calls. Discussing disasters where real lives were lost might seem ghoulish, but we approach our talks from a scientific perspective. I’m interested because he is; for a moment, we can live in the past together.
[3] By the time we return to Charleston, my father is gone—both in the sense that he isn’t who he used to be, and because he has moved away—and both of the old bridges have been demolished with dynamite. I imagine bits of metal and concrete scattered on the riverbed like twisted, dense bones.
[4] I was in Atlanta getting frozen yogurt with my now husband when we heard the news. We pulled the footage up on my phone to watch the flames, the crumbled asphalt, the traffic stranded for miles in the already heavy evening rush hour. The image of the gap where the road should be stayed with me for weeks.
[5] On my next phone call with my father, I brought it up. He had already studied the case. We had a fervent discussion, free of the long pauses we usually sit through. “The heat must have just been outrageous,” he said. “No way the material could take it.” For the first time, there was something we could equally linger on, dig into, obsess about. I began to keep an eye out for collapse, a running list of engineering failures to plug into our conversations. That singular, human fascination—regardless of our care, whatever we build will someday fall.
[6] When I discuss this with my father, I won’t bring up Maria’s illness. DD patients, including, of course, my father, typically can’t be convinced they need treatment, or that their delusions aren’t reality. “Madness” is off-limits, another reminder of the gap between us—when he was diagnosed, when he moved away, when our realities diverged. And Maria’s illness doesn’t really have to do with the bridge itself, although one must wonder if she wasn’t diagnosed, if John VI never took over, if Napoleon never…but I know the futility of “ifs.”
[7] Scientists don’t know for sure if DD is hereditary, in part because we don’t know much about the disorder generally, but there does seem to be a tenuous genetic predisposition. I searched for this information in a panic one night in my late teens: will I also lose touch with reality? The results: maybe. Later, when I got married, I told my husband that if I develop the disorder, he should tell my sister because she’s the only one I’ll believe. She told her husband to do the same. This is in part because delusions about cheating spouses are common, but also because we trust each other. “Will you believe her, though?” my husband asked. “Yes,” I said. Maybe.
[8] For my third-grade project, I had to build a suspension bridge out of marshmallows and toothpicks. My father and I built it together on the basement concrete. We used real metal Hot Wheels to test its load-bearing capability. In a week, the marshmallows were so dry they felt like pencil erasers, even after I licked them. “Remember?” he says sometimes during our phone calls, like that basement isn’t a half-life away, “remember when?”
[9] This is just blocks away from the Fukagawa Edo Museum, which I visited in 2014. I didn’t tell my father about the trip until I absolutely had to. Sometimes strange things set him off and it’s easier to avoid any unknowns. His response? General excitement for me. Sometimes I am still surprised, all these years later.
[10] Perhaps the most important and frustrating aspect of DD is its “encapsulated nature.” DD patients oscillate from being obsessed with their delusions, high-strung and intense, to being relatively normal, able to hold a pleasant conversation. This is difficult to describe. This is impossible to describe, really—the contrast between the two sides of my father, the valley in between. One section fails, the bridge fails.
[11] Before I was born, my family was in the Loma Prieta earthquake of ’89 in the Bay Area. A 1.25-mile segment of the I-880, just south of the Bay Bridge, collapsed into the lower level of highway below. The bridge was set for retrofitting the week after the earthquake. My father, still working at the time, was among the first to walk the broken bridge, pausing at the gap. We’ve covered this collapse; it is familiar ground. He often returns to those California memories during our calls, to the years where things were right.
[12] On the shore of the Sumida in 2014 with my classmates, I took pictures of the water, the boats, the grey sky, completely unaware of the history. Everywhere there are things that I miss.
[13] In the beginning, there was always the hope that my father could get better. The trouble with research is the resulting knowing. Many bridge failures are due to this hesitation to double check, to find the inconvenient answer, to slow down. There are no known cases of “full” recovery of DD. What would recovery even mean for my father? A recalibration of lived experience. A hastily built bridge from one reality to the next.
[14] This detail skewers me. I’m not sure I’ll share it with my father. I know he feels a low grade, constant guilt for having missed the details of most of my physical life—the car wreck, the month I was laid out with mono, the stitches on my finger from my first day of college when I slipped pitting an avocado. Maybe he would picture himself in the water with me, or he would picture us on the shore, standing together, because he would never lead me onto a failing bridge. He would see the warning signs. He’d have to.
[15] In our adulthood, my sister and I began visiting my father and grandfather at least once a year. Spending time with my father is fine, even enjoyable sometimes. He wants to teach us how to farm and has put together two huge binders filled with information, his own farming 101 textbook—grain yields, soil composition, marketing. When he helps us up and over the rim of the grain bin to stand on thousands of bushels of dried corn, our ankles sinking into the kernels, we trust him to know that we are safe.