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LIFEBOAT FOUNDATION SPECIAL REPORT
LIFEBOAT FOUNDATION SPECIAL REPORT
CRASH TEST CITIES:
PROTECTING AGAINST NUCLEAR BLASTS AND OTHER DISASTERS
By Lifeboat Foundation Scientific Advisory Board member Wil
McCarthy.
Print report!
Originally published January 10, 2005 on
SciFi.com.
It's a fact of life: Vehicles crash. Over an average 12-year lifespan,
about 20 percent of passenger cars and trucks will be involved in at
least one major accident. Being well aware of this, auto makers design
their vehicles with crashes in mind. There are other factors to
consider, such as comfort, price, appearance and fuel economy, but
today's cars are fundamentally built around crash safety. As a result,
while total traffic volume has increased 225 percent in the past 30
years, the annual number of road fatalities has actually declined by
about 50 percent worldwide, to around a million a year. That's still a
huge number, but it shows that safety measures really do work and are
worth the added cost. In a traffic-safety sense, not many of us would
go back to 1975 if we had the chance.
Unfortunately, there hasn't been any comparable progress in the safety
of our cities. This might seem an odd comparison, but cities actually
have a much higher accident rate than cars do. Think about it: Once
founded, cities rarely pack up and move. They're persistent artifacts
that last for thousands of years. And while large-scale natural
disasters are rarer than car accidents, they do come in a bewildering
variety: There are earthquakes, volcanoes, hurricanes, fires, droughts,
hailstorms, floods, landslides, blizzards, plagues, famines ... and,
yes, tsunamis.
MORE VULNERABLE THAN WE THOUGHT
Until recently, weather scientists believed that the heat islands and
airflow patterns of a major downtown area would repel a tornado. But on
May 12, 1997, a F1orida twister with 100-mph winds skittered through
Biscayne Bay and across downtown Miami. Miraculously, no one was killed
or seriously injured, but the myth was shattered: Cities are just as
vulnerable to these monsters as prairie farm towns. The only reason
more downtowns aren't hit is that they're so small against the vastness
of the world.
Even less likely is an asteroid strike, like the one that carved out
Meteor Crater in Arizona, or the 1908 devastation of hundreds of square
miles of forest in Tunguska, Siberia. To the best of my knowledge, in
all of history there's never been a recorded case of a city suffering
major damage from space debris; these strikes are rare, and our cities
just aren't that big a bullseye. But luck is a poor substitute for
safety; stand in one place for long enough and, sooner or later,
lightning will strike. Indeed, a meteor landing in the ocean could
easily produce coastal devastation on a scale that dwarfs last month's
tsunami (as in Arthur C. Clarke's classic novel,
Rendezvous With Rama).
When you consider man-made surprises like economic crashes, war and
terrorism, the picture gets even less rosy. Let's face it: Every city
on Earth is due for multiple disasters in its long, long future.
Through the lens of history, the urban crash rate is 100 percent.
Should we despair? No. But we should accept the inevitable and plan
accordingly. We should crash-proof our cities.
A good place to start is with an evacuation and shelter plan, coupled
to an effective emergency warning system. The lack of these in South
Asia is, I'm sure, a major contributor to the death toll there. For
sudden disasters like earthquakes, where advance warning is
problematic, we can beef up our science to improve forecasting and
toughen our building standards to reduce the dangers of collapse and
falling debris (see
Superbuildings Shake it Up). But what about that
quickest and most devastating of disasters, where a microsecond is
enough to hurl a city into flaming ruin? What about a nuke? Are we
helpless before such Promethean might? Thankfully, no — the answer
may be
as simple as building a wall.
DEFLECTING THE INEVITABLE
Well, OK, more like a berm or a dike. Imagine it with me, all right?
With a slope of 45 degrees, it'd be climbable by pedestrians and even
cars. Like a dam, it would be made of earth and rock, possibly sealed
in reinforced concrete. A heavy structure like that could take a lot of
pounding and still hold together. More importantly, it would deflect
shockwaves and shrapnel. Imagine the difference between a firecracker
closed inside your hand and one sitting in a bowl that directs the main
force of the blast upward. Which one will hurt you less?
Unfortunately, the bowl won't do much for a firecracker going off over
your head. In fact, depending on the position of the blast and the
exact geometry of the bowl, it might even reflect additional force into
your face. That's not good, obviously.
Still, a fairly simple workaround is to drill a bunch of holes through
our dike, connecting vertically and horizontally in a Swiss-cheesy sort
of way. This will break up any shockwave into dozens of smaller waves,
going different directions and arriving at different times. Acoustic
ceiling tiles use the same principle to break up sound and dampen
echoes. For better or worse, this would also impose rigid borders on
the districts and neighborhoods of a city. In our nuke-resistant
future, Chinatown will have a much harder time spilling over into
Little Italy.
I know what you're thinking, but there's no reason these blast walls
should have to be ugly. Like the levees of New Orleans or the canals of
San Antonio, the Great Wall of China or the skyscrapers of Manhattan,
they could be works of great beauty, snaking through our cities like
terraced, ivy-covered gardens. Far from blocking the view, these walls
will BE the view! They won't necessarily impede traffic, either, since
road and pedestrian tunnels could be an important part of the Swiss
cheese. In fact, let's get rid of subways and elevated tracks/roadways
altogether, and use the blast walls as an integral — and
aesthetically
elegant — part of our transportation network. People could live
inside
them, too, and in a flood or storm we can simply close off the holes
and use the barriers as actual dams and windbreaks. How cool is
that?
Ideally you'd want the dikes to be higher than the buildings they were
protecting, but this would use up a lot of costly real estate. We'll
have to make do with a larger number of smaller barriers instead, and
let the taller buildings take their chances. That, unfortunately, is
life in the real world: If you can't save everything, you should at
least do your best to save something. I'm imagining three of these
walls cutting east-west across the island of Manhattan, and four of
them slicing the L.A. Basin into the world's largest tic-tac-toe board.
But our disaster-hardened city has other aesthetic features as well:
large, raised central parks where debris can't fall, and where disaster
survivors can gather to wait for help. We'll have lakes and ponds full
of fresh, clean water, and cathedral-like underground galleries
stocked with food and medicine. A science-fiction movie set here would
get high marks for visual splendor!
But one of the most chilling images from last month's disaster is the
laughter. Yes, laughter: You can see it here and there in the faces of
fleeing people, who simply haven't grasped the enormity of what's about
to happen. They see the wave, yes, and they don't want it breaking over
their heads and getting them all wet. Beyond that, there doesn't seem
to be much of a plan. Not that I'm criticizing; we've all seen big
waves before, and experience does not tell us which ones are going to
wash entire coastlines out to sea. So, most importantly of all, our
future city is full of tough, clever people who, like good drivers,
have been trained to cope with the unexpected. In any age and any
danger, there's no better survival strategy than that.
REFERENCES
The Encyclopedia Britannica, 2004 Edition ("Tunguska
Event")
Tornado Skips Across Miami
The U.S. House Subcommittee on Highways and Transit Hearing on
Relieving Highway
Congestion through Capacity Enhancements and Increased
Efficiency
We Are All Safer: NTSB-Inspired Improvements in Transportation
Safety
Wikipedia: ("Car Accident")
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