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Secondary disaster

A secondary disaster is a new hazard or harmful effect caused by an original disaster. In Natural and Human Disasters, it includes things like landslides after earthquakes, disease after floods, or chemical spills after storms.

Last updated July 2026•Fiveable Content Team

What is the secondary disaster?

A secondary disaster is the damage that comes after the first disaster starts. In Natural and Human Disasters, you use this term for the follow-up hazards and impacts that are triggered by an original event, not the original event itself. If the first disaster is the trigger, the secondary disaster is the chain reaction that makes the situation worse.

The clearest examples are physical hazards. An earthquake can loosen slopes and set off landslides. A hurricane can damage a chemical plant or fuel storage site and create a spill. A flood can contaminate drinking water and create conditions for disease outbreaks. These are secondary disasters because they happen after, and because of, the first disaster.

Secondary disasters are not always separate, dramatic events. Sometimes they show up as longer-term consequences, such as displacement, food shortages, mental health stress, or the collapse of local services. In a disaster class, that matters because the harm is not finished when the storm passes or the ground stops shaking. The original event can set off problems that last weeks, months, or longer.

A useful way to think about it is cause and chain reaction. Primary disasters start the disruption. Secondary disasters expand the damage, often by hitting systems that were already weakened. Roads, hospitals, water systems, power lines, and communication networks can all fail after the first event, which makes recovery harder and can raise casualty rates.

This term also connects to disaster planning. Emergency managers try to predict what secondary hazards are most likely in a region, then build response plans around them. For example, a coastal community may plan for flooding plus contaminated water, while an earthquake-prone area may prepare for landslides, gas leaks, and infrastructure failures. The point is to treat the disaster as a sequence, not a single moment.

Why the secondary disaster matters in Natural and Human Disasters

Secondary disaster is one of the best terms for showing why disaster impacts spread. It helps you explain why the worst outcomes are often not the first visible ones, but the chain of damage that follows. In Natural and Human Disasters, that shift in thinking matters because many case studies are really about cascading harm, not just one event.

The term also connects directly to mitigation and preparedness. If you can identify likely secondary disasters, you can explain why early warning systems, evacuation plans, backup water supplies, and hazardous-material safeguards matter. That is the difference between a response plan that stops at the headline event and one that actually reduces total losses.

It also helps you compare disasters across types. Earthquakes, hurricanes, floods, and technological accidents can all trigger secondary disasters, but the mechanism changes. Once you can name the secondary effect, you can trace how the original hazard damaged a system and then caused a new problem in society, health, or the environment.

Keep studying Natural and Human Disasters Unit 1

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How the secondary disaster connects across the course

Primary Disaster

The primary disaster is the original event that starts the damage, such as the earthquake, flood, hurricane, or explosion. Secondary disasters come after that first event and depend on it. When you separate the two, you can trace the full chain of harm instead of treating everything as one undifferentiated disaster.

Cascading Events

Cascading events describe the step-by-step sequence where one failure triggers another. Secondary disasters are often part of that chain, especially when one hazard damages infrastructure and then creates a new problem like contamination, fires, or service outages. This term helps you explain how disasters spread through connected systems.

Disaster Recovery

Recovery gets harder when a secondary disaster hits because the community has to deal with more than the original damage. A flood might be followed by a disease outbreak, which slows rebuilding and stretches public health resources. This connection shows why recovery plans need more than short-term cleanup.

Technological Disaster

Some secondary disasters involve technology or industrial systems, like a chemical spill after a hurricane or a power failure after an earthquake. That makes technological disaster a useful nearby term because the second event can be human-made even when the first one was natural. It shows how natural hazards can trigger industrial risk.

Is the secondary disaster on the Natural and Human Disasters exam?

A quiz question or case study may ask you to identify whether a damage report describes the original disaster or a secondary disaster. You might also be given a scenario, like an earthquake followed by a landslide, and asked to trace the cause-and-effect chain. In a short response, use the term to explain how one hazard created another and why the total impact grew.

On map or image questions, look for signs of follow-up harm, such as damaged water systems, contaminated areas, displaced residents, or infrastructure collapse after the initial event. In essays and class discussion, the strongest move is to name the primary disaster first, then explain the secondary effects that made recovery harder or increased casualties.

The secondary disaster vs Primary Disaster

Primary disaster is the original event that begins the damage, while secondary disaster is the later harm caused by that event. A hurricane is the primary disaster, but flooding, contamination, and disease outbreaks that follow can be secondary disasters. If you mix them up, you lose the chain of cause and effect.

Key things to remember about the secondary disaster

  • A secondary disaster is a later hazard or harmful effect caused by an initial disaster.

  • It can be a physical event, like a landslide after an earthquake, or a social and health effect, like displacement or disease after flooding.

  • Secondary disasters often make recovery slower, more expensive, and more deadly than the first event alone.

  • Good disaster planning looks for likely secondary hazards, not just the original disaster.

  • If you can trace the chain from cause to follow-up damage, you are using the term correctly.

Frequently asked questions about the secondary disaster

What is secondary disaster in Natural and Human Disasters?

A secondary disaster is a later harmful event or condition caused by an initial disaster. In this course, it includes things like landslides after earthquakes, chemical spills after hurricanes, or disease outbreaks after floods. It is the follow-up damage that makes the overall disaster bigger.

What is the difference between a primary disaster and a secondary disaster?

The primary disaster is the original event, such as the earthquake, flood, or storm. The secondary disaster is the chain reaction that follows, like infrastructure failure, contamination, or a health crisis. A good way to separate them is to ask which event started the damage and which one was triggered by it.

Can a disease outbreak be a secondary disaster?

Yes. If flooding contaminates water supplies or displaces people into crowded shelters, disease can spread as a secondary disaster. In this course, that kind of example shows how one event can create public health risks long after the initial hazard passes.

Why do secondary disasters matter in disaster planning?

They matter because the first disaster is often not the whole problem. Emergency plans that account for secondary hazards can reduce deaths, protect infrastructure, and speed recovery. That is why early warnings and backup systems are such a big part of disaster management.