BY NOW, everybody knows that security at Sea-Tac is spotty, biological agents are extremely easy to purchase and manufacture, and there's virtually no way to arm a city to withstand an attack like that against New York's twin towers. So, short of forming a police perimeter around the city, what can Seattle do to protect itself against an attack? Are we vulnerable? If so, where?
Experts agree that, among weapons of mass destruction available to terrorists, biological weapons are by far the greatest threat to human life and safety (see accompanying article). Anticipating that an attack could come from anywhere, at any time, the city formed a surveillance and response plan against bioterrorism more than two years ago and sent out an alert to hospitals, microbiology labs, and infectious disease specialists after the attacks last Tuesday. The state National Guard also has a response team for chemical, nuclear, and biological threats, which include smallpox, anthrax, and plague.
Not all terrorism is so exotic. According to Charles Roeder, a professor of civil engineering at UW, structures like highway bridges, railroads, and buildings are particularly open to potential attacks. "We live in a very open society, so things like bridges could be extremely vulnerable to some kind of [attack]," Roeder says. "If someone has a small truck full of explosives and parks it and walks away and five minutes later it blows up, I don't think there are five bridges in the state that could stand that kind of explosion." Moving the truck to the bridge's structural supports would increase the potential for damage, Roeder says. On the I-5 bridge, for example, the damage would be "much, much more severe" if a bomb were placed on the lower deck, close to the bridge supports. Earthquake protection—what city officials call "seismic strengthening"—helps some, although a bomb would test the capabilities of any retrofitted structure.
That also goes for buildings, although it may not matter much. "I don't think any of the buildings downtown would have necessarily been able to endure what the World Trade Center buildings" were subjected to in terms of heat and structural damage, Roeder says. We could build structures that could withstand such impacts, Roeder notes, but only at great cost, in terms of both money and aesthetics. "If these planes had hit one of the pyramids in Egypt, the plane would be a pile of rubble and there'd be a huge fire, but the pyramids would probably have not been damaged much," Roeder says. "The question is, do you want your office building to be in a pyramid of Egypt or do you want to be in one of those nice glass-walled buildings downtown with a view?"
The electric grid, a complicated system of generators, transmission wires, substations, and radial lines, is also potentially vulnerable, though not as much as you might imagine. Generators, most of them located far away from the city, are designed with redundancy built in—if one goes out, another one 10 miles down the road can pick up the slack. Substations, which gather electricity from transmission towers and distribute it to neighborhoods, also have some overlap. Where the city is most vulnerable is its transmission lines, which are (unlike generators) unfenced and unprotected; according to Richard Christie, an associate engineering professor at UW, you'd have to take out seven or eight transmission towers to do significant damage. "The grid is designed and operated so that the outage of a small number of these transmission lines doesn't effect the operation of the grid."
But if a large number of transmission towers was destroyed at once, particularly at a time of the year when the system was near capacity, the city's electric system could be shut down. "If you could coordinate seven simultaneous explosions, you could basically cut the city of Seattle from the electric grid." Restoring the city would involve fabricating new towers, putting them in place, and replacing the system of transmission lines. "It would take a minimum of several days" and possibly longer to restore the system, depending on how many towers were down. And protecting the towers would be a logistical nightmare: Short of stationing armed guards beneath every tower, fences and motion-detection systems would be the only alternatives. And those would likely be expensive and relatively ineffective, Christie says.
City emergency officials, aware that the city is vulnerable to attack, have developed a four-point response plan to deal with emergencies ranging from earthquakes to bombings to the destruction of the city's communications system. But while the system has worked well in cases like last February's earthquake, it's untested against terrorism on any scale. As Jim Mullen, director of the city's Office of Emergency Management points out, "You're only as good as the last event."