Earthquake

Cities depend on networks of lifeline structures to distribute water, power, and food and to remove sewage and waste. These networks, whether power lines, water mains, or roads, are easily damaged by earthquakes. Elevated freeways collapse readily, as demonstrated by a section of the San Francisco Bay Bridge in 1989 and the National Highway Number 2 in Kobe, Japan, in 1995. The combination of several networks breaking down at once multiplies the hazard to lives and property. Live power lines fall into water from broken water mains, creating an electric shock hazard. Fires may start at ruptured gas mains or chemical storage tanks, but many areas may not be accessible to fire trucks and other emergency vehicles. Even if areas are accessible, there may not be water for fire-fighting. The great fire that swept San Francisco in 1906 could not be stopped by regular firefighting methods and entire blocks of buildings had to be demolished to halt the fire. Most of the 143,000 people killed in Tokyo and Yokohama because of the 1923 Kwanto perished in fires.

Famine and epidemic disease can quickly strike large displaced populations deprived of their usual food distribution system, sanitation services, and clean water. Furthermore, collapsed hospitals may be of no use to a stricken community that urgently needs medical services. After an earthquake, relief operations commonly offer inoculation against infectious diseases. In countries that do not have sufficient organization, trained personnel, or resources to handle an earthquake-generated refugee population, more people may die of secondary causes than the direct effects of seismic shaking. Even in the most prepared countries, the disruption of networks may prevent relief operations from working as planned. In the aftermath of the January, 1995, earthquake in Kobe, Japan, plans for emergency relief made before the disaster did not work as well as planned. Local residents, wary of the danger of aftershocks, had to live outdoors in winter without food, water, or power.