Lawrence Hall of Science
SII--The Science Information Infrastructure

Big Trouble In Earthquake Country

Part B: Background Information-

Read through the following material to gain a better understanding of concepts and issues associated with disaster management.

Page Index:

Defining Disaster

Physical and Social Nature of Disaster

Physical Nature of Disaster

Social Nature of Disaster

Emergencies and Disasters


All Hazards Approach To Disaster

Phases of Disasters


Defining Disaster
In this section, you will become familiar with some key ideas related to disaster. Disasters have both a physical and social component. Second, for planning and response purposes, disaster managers need to discriminate between emergencies and disasters. Responding to everyday emergencies, as we will see, requires a different management approach than responding to the larger more disruptive social consequences of a disaster. Next, we advocate disaster managers take an "all-hazards" approach to disasters. Specifically, although disasters may result in varying types of physical damage and destruction, they typically generate the same type of social needs. Thus, lessons learned from one type of disaster can be applied to another. Finally, we discuss the four main phases of disaster that managers currently use to handle disasters. An important point central to effective disaster management is that a disaster must be considered social rather than a technological, geological, or meteorological event.

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The Physical and Social Nature of Disaster
The word disaster has multiple meanings. To some, it may mean the threat or possibility of a particular event (e.g., flash flood, chemical spill). To others, it may mean the actual disaster agent that creates death and destruction (e.g., hurricane, earthquake, explosion). The word disaster may also refer to the physical damage created by the agent (e.g., shattered and destroyed homes and trees revealing the path of a tornado). Finally, the word disaster may reflect how the agent affects human beings. The human toll could mean death and injury. Also, disaster disrupts and changes the everyday activities of our life. Next, we discuss these different aspects of disaster, and highlight the importance of understanding the social nature of disaster.

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The Physical Nature of Disaster

Geological and meteorological events are part of our natural environment. From a geological time perspective, earthquakes, landslides, floods, hurricanes, and tornadoes are quite common. For example, since 1900, numerous major hurricanes have struck the east and gulf coasts of the United States. Similarly, between 1980 and 1987, over 12,000 earthquakes over a richter magnitude of 5.0 have rattled the Continental United States.

Yet, the occurrence of these events and the physical destruction alone do not create disasters. For example, the New Madrid Earthquakes of 1811-1812, the most devastating earthquakes known in the United States over the last 200 years, illustrate our point. The earthquakes originated around the Memphis/St. Louis area. Geologists estimate the force of the earthquakes at 8.1 on the Richter Scale. The earthquake altered the course of the Mississippi and rang churchbells as far away as Washington D.C. Despite the strong physical impact, this event was not necessarily a "disaster". Few people lived in this area. Thus, the relative social consequences and problems of the disasters were limited.

Today, the same earthquake would not only kill and injure thousands, disrupt not only all social activities in the midwest, but also effect people and organizations throughout the United States. For example, the Federal Emergency Management Agency (FEMA) recently projected what the impact of a similar 1811 earthquake would be in the St. Louis, Missouri area today. Between 270 to 1400 people would be killed and between 1,060 to 3,950 would have serious injuries. People would be without electricity, water, gas, and sewage systems for days if not weeks. Extensive damage to highway and rail systems would inhibit transportation for days and impair transportation for weeks. As a result, victims would be on their own for a couple of days. Social disruption would be enornmous in just the St. Louis area alone. Other parts of the midwest would likely suffer the same types of social effects, further slowing important aid and assistance to victims. Thus, the disaster agent or the physical destruction left by the agent do not create a disaster. Rather, as we discuss next, disaster managers must be most concerned about the amount of social disruption generated by the disaster agent or the destruction created.

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The Social Nature of Disaster

The potential for disaster occurs when people reside in areas prone to earthquakes, hurricanes, floods, tornadoes, hazardous chemical incidents, and other similar events. If people selected not to reside in floodplains, we would not have flood disasters. If people choose not to live along earthquake faults, we would not have earthquake disasters. Similarly, if people did not live next to hazardous facilities (e.g., chemical plants), such events as the Bhopal, India, or Institute, West Virginia, disasters would not occur.

Yet, for a multitude of social, political, economic, historical, and geographical reasons, people reside where risks exist. One of the more recent examples of the interaction of the people with nature is the Great Mississippi River Flood of 1993. For historical reasons, people from New Orleans to Minneapolis/St. Paul lived along the Mississippi. During the colonization of the midwest, the Mississippi River served as an important means of transportation of people and products up and down the river. Towns developed and grew upon this economy. As more people settled along the river for commercial and agricultural reasons, they also put themselves at risk for flooding.

People live in various types of hazardous places. In some cases, individuals and communities make adaptations to live more safely in these areas. For example, individuals, communities, and the state recognize the major earthquake hazards in California. Individuals and communities plan for disaster. People and cities treat disaster exercises seriously. City and state governments have passed laws to encourage and enforce mitigation efforts. To illustrate the importance of the social dimension of disaster, we next compare the Loma Prieta Earthquake of 1989 to the Mexico City Earthquake of 1985.

The October 17, 1993, Loma Prieta Earthquake registered a 7.9 on the Richter Scale. Overall, loss of life, injuries and damage were limited. The effects of the earthquake killed between 62 to 66 people, injured about 3,700 people, and left around 13,000 people homeless. Except for Watsonville, Santa Cruz, and some parts of San Francisco and Oakland, the affected bay area experienced minimal social disruption. Without mitigation and planning (a people component), the social impacts could have been much worse.

The Mexico City earthquake of 1985 registered 8.1 on the Richter scale. Although slighty higher than the Loma Prieta earthquake, at least 10,000 died in Mexico City and another 50,000 victims were injured. Over 800 buildings, including hospitals, hotels, schools, and businesses were destroyed. Experts estimate the earthquake created over $5 billion worth of damage.

Although each of these earthquakes registered similar numbers on the Richter scale, the amount of destruction and social disruption varied greatly. The loss of lives, injuries, and social disruption was not as great as the similar social consequences with the Mexico City earthquake. Social factors such as disaster planning, effective mitigation programs (e.g., building code enforcement, earthquake survival programs) all combined to lessen the social effects of the Loma Prieta earthquake.

In summary, we advocate that disaster managers consider disasters social events. Rather than solely focusing upon the disaster agent or the physical destruction caused by a disaster, the disaster manager must consider the social consequenses generated by the event. Disasters and managers should consider how people's lives are disrupted or how organizations must adapt to a changing uncertain environment. Therefore, the human element is the crucial dimension in disaster preparedness, response, recovery and mitigation. Disasters are social events.

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Emergencies and Disasters
Above, we argued that disaster planners and managers must think of disasters as social, not physical events. In this section, we elaborate upon this idea. We make an important distinction between every day life crises, disasters and catastrophes. Much of everyday life, including our own lives, is predictable. Consider your daily weekday routine. Like millions of others in the United States, you probably awake in the morning, use the toilet, shower, have breakfast, travel to your job, work for four hours, eat lunch, work another four hours, and travel home. Once home, you may watch the news, eat supper, do a few chores around the house, read, watch television, and go to bed. In addition, you probably do various activities associated with your daily routine with little or no thought. For example, you turn on a faucet to get water. You flick a light switch and light fills a room. You set out the garbage, and a city crew picks it up. You get on the highway and drive to work. You turn on your computer and browse this and other web sites. You go to the supermarket and get a weeks worth of food. If one part of our daily life does not work, it may throw part of our routine out of synch.

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Emergencies may interrupt our lives. A car accident may interrupt our drive home. A family member may have a heart attack. A neighbor's house may catch on fire. With all of these cases, we rely upon emergency response personnel. Police, fire, and paramedic personnel may assist with the car accident, heart attack, or house fire. For a while, the daily patterns of those directly affected will differ. For the rest of a community, however, other than the inconvience of pulling off the side of the road to let an emergency vehicle pass, being stuck in a traffic jam, or being awakened by a siren, lives and daily routines continue unchanged.

Also, emergencies generally affect only a small portion of a community. A heart attack, traffic accident resulting in injury or death, or a house fire, may be terrible tragedy for the family and close friends of the victims. Such tragedies may disrupt for a week, month, or even a year a family's routine. However, such events do not disrupt the overall smooth functioning of a community. Outside of the family and close friends, life goes on.

In addition, the local community has various organizations in place to handle these day to day emergencies. Fire Departments routinely handle fires, traffic accidents, heart attacks, and similar incidents. Other local organizations such as police departments, public works departments, and the utilities, all assist effectively in handling such crises when called upon. Hospitals can easily handle the daily routine medical emergencies. Red Cross and Salvation Army may help those who have lost their home in a fire. In fact, local citizens would be angry if local government and other associated organizations could not handle such "routine" accidents and events.

Although not routine to victims, these emergency response organizations deal with car accidents, medical emergencies, or house fires on a daily basis. They have designed their organization specifically to respond to such events. These are routine events. In most cases, these emergency response organizations do not need to draw upon outside resources or help to respond.

Finally, a car accident, medical emergency, or a house fire does not upset the routine of a whole community. Local government and services continue with their daily service delivery, and businesses stay open. Such incidents may be personal tragedies. A family's daily routine may be disrupted. However, life continues for the community. Thus, a crisis or emergency that may be a terrible event for a specific individual, family or group. Yet, the local community has a system in place to handle such events, the system often routinely handles these events, and these events do not upset the patterns or routines of larger portions of the community.

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All Hazards Approach To Disaster
For various reasons, people have tried to make distinctions between various types of disasters. For some, each disaster is seen as a special unique event. As a result, the media and others will distinguish between two categories of disasters: natural and technological disasters. Also, local communities write plans based on the numerous hazards that may exist in a community.

When looking at the overall general nature of the social aspect of disaster, however, an important fact develops. The social aspects and problems of disasters are generally the same regardless of the type of disaster. For example, the problems of getting a local community to prepare for a disaster are the same regardless of the type of the impact. The problems of warning people about an oncoming disaster are the same whether it is a chemical release, tornado, or flash flood. Specific examples of the similarities of problems of preparedness or warning will be given later in following modules.

Policy experts have also recognized that the all hazards approach is the best way to handle disasters. FEMA's concept of Comprehensive Emergency Management stresses the all hazards approach for disaster purposes. Thus, FEMA recognized that whether a community was dealing with a natural disaster, technological disaster, or nuclear attack, the disaster management strategies are generally the same regardless of the type of disaster agent. The Federal Government's catastrophic disaster plan, known as the Federal Response Plan (FRP) is a good example of the all hazards approach. The FRP designates how various federal agencies should interact among each other and with local government in the case of a catastrophic disaster. The general format plan makes no real distinction regarding the type of disaster that could occur.

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Phases Of Disasters
Disaster managers often talk about different phases of disasters. The four phases of disaster include preparedness, response, recovery and mitigation. Preparedness refers to the activities undertaken by individuals, groups, families, organizations or countries to handle a disaster when it strikes. Such activities may include making a plan, exercising a plan, or stockpiling food. Response are those activities that pertain to the initial activities after the disaster has struck. This may include search and rescue activities, clearing debris, activiting the Emergency Operating Center (EOC), and feeding and sheltering victims (and responders if necessary). Recovery refers to the activities involved in getting a community back to its pre-disaster status. This may include the rebuilding of homes and businesses, or obtaining funds from private, local, state and federal sources. Finally, mitigation represents those activities that can lessen the impact of a disaster before it strikes. Structural mitigation includes the building of levees or dykes, or raising the foundation of homes in floodplains, or using specific building techniques to withstand such events as hurricanes or earthquakes. Social mitigation may refer to a number of different activities inlcuding people. One type of example is the institution of zoning regulations or laws to lessen the impact of a potential hazard. This may inlcude zoning regulations to prevent residential homes in specific types of floodplains or located too close to hazardous facilities. Another example is educating people about the existence and how to heed a local warning system.

The phases of disaster are useful tools for disaster management purposes. We will make reference to the disaster phases throughout the modules. However, the reader should not take these phases too literally. First, rather than being specific or discrete phases, at least a moderate degree of overlap can exist between phases. For example, following the Lancaster, Texas Tornado, we observed both response and recovery events occuring at the same time. In some areas of the city, we observed just 36 hours after the tornado the cleaning of debris off city streets so other emergency vehicles could enter the city and further assist with other debris removing efforts (response effort). At the same time, we observed a group of people picking up bricks and stacking them neatly so that the building could be quickly rebuilt (recovery).

Second, some activities are difficult to distinguish from one phase to another. For example, educating homeowners on ways to lessen the impact of flooding represents a successful flood mitigation strategy. Also, local officials can educate the public about effective preparedness strategies to undertake for a specific type of hazard. Thus, education can both lessen the impacts of disaster (mitigation) and assist people in knowing what to do during the response (preparedness). Overall, rather disaster phases overlap greatly but yet provide us a means to organize activities when dealing with disasters. The four phases of disaster are an effective means to organize disaster activities. Yet, disaster phases should not be taken too literally.

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In this section we have focused on some important terms and definitions essential for understanding disaster management. First, we differentiate between the physical and social aspects of disaster. Although the physical components of disaster are important, disaster planners and managers must focus on the social aspect of disasters. Simply put, disasters are people problems. Thus, disaster managers must see disasters as "people problems" both in the realm of helping the victims and managing disaster related organizations.

Second, we distinguish between an emergency and disaster. Emergencies are events that emergency response organizations (fire, police, Red Cross) handle on a routine basis. These organizations do not need to rely upon outside help. Also, the event impacts only a small part of the community. Most members of the community do not have their daily routine disrupted. A disaster, however, creates unmet needs in a community. Emergency response organizations must draw upon help from outside sources, and the event disrupts the daily routine of the community for days if not longer.

Third, we advocate an "all hazards" approach to disaster management. We argue that basic human behavior and organizational management issues are generally the same across all types of disasters. Thus, lessons learned for one type of disaster (e.g., how to warn effectively people for a hurricane) can be applied in an equally effective fashion to another type of disaster (e.g., how to warn people effectively after a major chemical explosion or for a tornado). Finally, we define the four phases of disaster (e.g., preparedness, response, recovery, and mitigation). The understanding and use of these four phases are central in creating an effective disaster system. Yet, we must also understand that the phases are not discrete events. Rather, there is a great deal of overlap among all phases.

Disasters create organizational management problems. Effective disaster management begins, however, through knowledge of what typically occurs during and following a disaster.

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Institute Of Emergency Administration And Planning


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