Perspective | The beauty — and the terrible demise — of the Key Bridge

The video of the Francis Scott Key Bridge’s collapse now exists as a global icon, giving several billion people a seemingly intimate and shocking memory of a bridge they may never have seen or heard of until social media and journalism made it ubiquitous.

The video is fascinating, terrifying, mesmerizing, and it may confirm superstitions we often feel about things beyond our individual comprehension. How is it that airplanes stay up in the air, and tunnels don’t collapse under the weight of water and earth? Even the most agnostic brains will make quiet and reflexive supplication for protection before crossing a bridge as dramatic as the one that collapsed this week.

Livestream video shows the moment the cargo ship Dali crashed into Baltimore’s Key Bridge early March 26. (Video: Streamtime Live Via Youtube)

The loss of the bridge is first a human tragedy, for those injured or killed by its collapse. And then it is an economic shock, with a radiating toll that won’t be fully understood for years, and perhaps decades. But it’s also a powerful symbolic shock, given the metaphorical power of bridges as a form of connection, a symbol of our technical prowess, a point of civic pride and persistent desire to master and reshape the landscape.

On the day the Francis Scott Key Bridge opened in March 1977, the Baltimore Sun celebrated the views from the top of its giant steel-truss crossing: “In every direction from the harbor span lie dramatic vistas of the Port of Baltimore.” That included a marine terminal, the giant Bethlehem Steel plant and the Penn Central Canton rail yards. After delays and cost overruns, the new bridge was welcomed as yet more proof of the city’s ambition, its engineering prowess and its economic might.

The city hasn’t fared well in recent decades, and the newspaper’s breathless boosterism for new infrastructure sounds strangely dated. So, too, the name the bridge bears. We remember Francis Scott Key not only as the author of our national anthem’s lyrics, but as an enslaver and staunch opponent of abolitionism. There is little enthusiasm for creating new memorials to him.

But the Key bridge was a marvel, and it remained a high point of any drive around the city of Baltimore until its collapse, early Tuesday morning, after being struck by a giant container ship. Since the middle of the last century, American infrastructure has been laid heavily and bluntly on the social and natural landscape. Interstate highways were plowed recklessly and cruelly through urban areas, too often dividing and polluting neighborhoods of the poor and people of color. Outside of cities, the standardized width, grades and slopes of the interstate highways seem designed to deny any connection to topography.

The Key Bridge, however, was a rare moment when your car seemed to soar, giving you a not-quite-bird’s-eye view of the peculiar geography and history of the East Coast. Any trip by train or highway along the heavily populated Mid-Atlantic seaboard involves myriad long bridges and tunnels to cross the bays, estuaries and wide rivers that stretch deep into the coastal plains. Baltimore is situated where it is because it provides safe harbor for ships. And many seemingly landlocked cities, like Richmond and Fredericksburg, lie near the last navigable point of major rivers that stretch fingers of trade and commerce into the country’s interior. Unlike the tunnels that carry Interstate 95 and I-895 across the harbor and Patapsco River, the Key Bridge offered an exhilarating experience of the landscape, and its connection to the early economy of colonial America.

A symbolic shock like Tuesday’s tends to lead the public toward darker emotions — horror, of course — but also fear, suspicion and even cynicism.

Like the photographs that emerge from wars or disaster, bombings, floods and earthquakes, the video of the bridge collapse doesn’t explain the things that feel most inexplicable. The more you watch it, the less it yields, until finally the mind flirts with some kind of metaphor or parable to make sense of it. Perhaps there is a fable of American decline or corruption or incompetence. It’s best not to amplify or extend the toxic theories that circulated in the immediate aftermath. But they are symptoms of the same phenomenon, a sudden, overwhelming craving for meaning, into which unscrupulous people will project their ugliest fancy.

In the video, the bridge faltered first on the left side of the frame, then in the center, and then its long truss snapped and the right span fell, all in a matter of a few seconds. The speed of its failure offers the first of the fables, that something must be desperately wrong with the design for it to collapse so quickly. But its rapid failure is directly related to the properties of a long, steel-truss bridge. Put simply: Each part of this bridge’s main span is helping the other parts do their work. Its elements are integrated into a whole, which allows less steel to bear more weight.

The engineering is fundamental to the bridge’s beauty. The main span of the Key Bridge, the one that flew high above the river allowing passage to ships beneath, sat on its four piers like a bird. Seen from a distance, it looked spidery and delicate. For centuries, advances in bridge technology have created a tension between efficiency — the ability to span greater distances with less structure — and an intuitive belief that bridges should be solid, heavy, formidable in their construction. When 18th-century London debated the design of a new Blackfriars bridge, Samuel Johnson argued vehemently for a heavier structure of semicircular arches, rather than what was built, a series of slightly more graceful semielliptical arches.

“The first excellence of a bridge built for commerce, over a large river, is strength,” he wrote in a 1759 public letter. He lost the argument, but his appeal to what seemed common sense — the old, round Roman arch was stronger and thus always preferable — still haunts our thinking about infrastructure, if we think of each project individually and unrelated to larger needs and systems.

But infrastructure isn’t just a collection of individual projects, but a larger collection of problems and responses. And to meet those demands efficiently, you build not the strongest bridge possible in every case, but the strongest necessary to meet a reasonable set of expectations and risks.

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The giant steel bridges the world began building in the 19th century embody the man-made sublime, delighting the eye and terrifying the mind with their ambition. Walt Whitman used to visit the great Eads Bridge in St. Louis to feast on the poetry of its design: “I have haunted the river every night lately, where I could look at the bridge by moonlight.” It was, he said, “a structure of perfection and beauty unsurpassable,” a sentiment more common when this technology was still new, and dazzling, and wasn’t routinely value-engineered out of the final design.

But when Benjamin Baker and John Fowler designed the equally beautiful Forth Bridge in Scotland, they had to demonstrate the engineering in a way that made its forces of tension and cantilevers intelligible to ordinary people. So, they had a picture taken of three men using chairs, broomsticks, weights and their arms to reproduce the logic of his design. In the middle, miraculously suspended in midair, sat Kaichi Watanabe, a Japanese engineer who was studying in the United Kingdom.

The image not only explained the bridge, but made it human, extending its metaphorical power as a collective human project with collective benefits. It enacted in an almost comical way the basic trust we place in engineering that defies our individual comprehension.

There will be investigations and essential lessons learned from the tragedy earlier this week. People trying to bypass Baltimore will be inconvenienced and people who live there will be unnecessarily burdened, but there will also be workarounds and adaptation. And slowly, the images, fables and analogies that govern our thinking about bridges will revert to where they have been for centuries: They are a means of connection, essential, often beautiful, sometimes terrifying, and never more so than when they are miraculous in their efficiency of design.

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