One of the shows on NHK this morning was talking about earthquake preparedness. Recently there’s been something of a boom in literature about what to do in the event Tokyo spontaneously falls down. If you go to bookstores around here, you see competing lines of evacuation maps, survival guides and the like.
The blurb I caught on my way to work was about evacuation. After a major earthquake, the trains stop running and the elevated expressways are likely to have fallen down in places (think Kobe, 1995), so the only way to get out of the city is on foot, taking surface routes.
This doesn’t sound too bad until you realize how many people are in the city, how narrow many of these surface routes are, and how likely they are to be blocked in places by falling power poles and other debris. One think-tank wonk made a computer simulation of an evacuation of downtown Tokyo, and figured that the streets in shitamachi (i.e. the area around Tokyo Station and Ginza) would be crowded to the extent of about 11 people per square meter. That’s about the maximum number of people you can squeeze into a square meter; imagine the worst Tokyo subway cars at rush hour, expanded to the size of an arterial street.
Yet another reason why we need flying cars NOW.