DISASTER AND DISASTER MANAGEMENT
What is a Disaster
Disaster is an undesirable occurrence resulting from forces that are largely outside human control, strikes quickly with little or no warning, which causes or threatens serious disruption of life and property including death and injury to a large number of people, and requires therefore, mobilisation of efforts in excess of that which are normally provided by statutory emergency services.
Definition for Indian official purposes: Disaster means a catastrophe, mishap, calamity or grave occurrence in any area, arising from natural or man-made causes, or by accident or negligence which results in substantial loss of life or human suffering or damage to, and destruction of, property, or damage to, or degradation of, environment, and is of such a nature or magnitude as to be beyond the coping capacity of the community of the affected area
Disaster is assessed on the basis of the following features:
• Disruption to normal pattern of life. Such disruption is usually severe and may also be sudden, unexpected and widespread.
• Human effects such as loss of life, livelihood and property, injury, hardship and adverse effects on health
• Effects on Social Structure such as destruction of or damage to infrastructure, buildings, communications and other essential services.
• Community needs such as shelter, food, clothing, medical assistance and social care.
AGGRAVATING FACTORS OF DISASTERS
Poverty
All disaster studies show that the wealthy among the population are less affected and also able to recover quickly. However, poverty generally makes people more vulnerable to all the impacts of disasters. It is only due to poverty that poor people are forced to live in more vulnerable areas such as flood plains of rivers.
Population Growth
If there are more people and structures where a disaster strikes, there will be more impact. Increasing number of people will compete for limited resources (e.g., employment opportunities) which can lead to crisis-induced migration. This aggravates the disasters in developing countries.
Rapid Urbanisation
Rapid and unplanned urbanisations make the poor people to live at unsafe places and with least resources at their disposal. Many of the landslides or flood disasters are closely linked to rapid and unchecked urbanisation which forces low-income families to settle on the slopes of steep hillsides or banks of rivers.
Transitions in Social Practices
All societies are under a continual state of transition which is often disruptive and uneven, leaving gaps in social coping mechanisms and available technology. These transitions include nomadic population that become sedentary, rural people who move to urban areas, and both rural and urban people who move from one economic level to another.
Environmental Degradation
Many disasters are either caused or aggravated by environmental degradation. Deforestation leads to rapid rain runoff, which contributes to soil erosion and flooding.
Lack of Awareness and Information
Lack of awareness and proper information usually converts a hazard into a Disaster. This ignorance may not necessary be due to poverty, but due to a lack of awareness of what measures can be taken to build safe structures on safe locations.
War and Civil Strife
War and civil strife are regarded as hazards, that is, extreme events that produce disasters. The causal factors of war and civil strife include competition for scarce resources, religious to ethnic intolerance and ideological difference.
KEY DISASTERS IN INDIA
Earthquake
Earthquakes are considered to be one of the most dangerous and destructive natural hazards. The impact of this phenomenon is sudden with little or no warning, making it just impossible to predict it.
Therefore, the best strategy is to make preparations against damages and collapses of building and other man-made structures, About 50-60% of total area of the country is vulnerable to seismic activity of varying damage potential. Most of the vulnerable areas are generally located in Himalayan and sub-Himalayan regions extending from Kashmir to Arunachal Pradesh, Kutch and in Andaman and Nicobar Islands.
Suggestions: In our present state of knowledge, earthquakes can neither be prevented nor predicted in terms of their magnitude, or place and time of occurrence.
Therefore, the most effective measures of risk reduction are pre-disaster mitigation, preparedness and preventive measures for reducing the vulnerability of the built environment combined with expeditious and effective rescue and relief actions immediately after the occurrence of the earthquake.
Floods
Floods occur when large volume of water from heavy rainfall and/or river spill is not able to drain off quickly through normal channels.
India is the second most flood affected country where flood is a common natural disaster especially during the later part of the monsoon period. In India the most affected states due to floods are Bihar, Uttar Pradesh, North-Eastern states, Odisha & West Bengal etc.
The effects of flood on the affected population are manifested in the form of inundation marooning, drowning, loss of habitat roads, communications, destruction of crops, industrial shutdown, loss of wages, diarrhoea diseases, respiratory infections etc.
Causes of Floods
Inadequate capacity within the banks or the river to contain high flows,
River bank erosion and silting of river beds,
Landslides leading to obstruction of flow and change of the river course,
Synchronization of floods in the main and tributary rivers,
Retardation of flow due to tidal and backwater effects,
Poor natural drainage,
Cyclones and storm surge,
Cloud burst and flash floods.
Suggestions
• There should be a master plan for flood control and management for each flood prone basin.
• Adequate flood-cushion should be provided in water storage projects, wherever feasible, to facilitate better flood management.
In highly flood prone areas, flood control should be given overriding consideration in reservoir regulation policy even at the cost of sacrificing some irrigation or power benefits.
• While physical flood protection works like embankments and dykes will continue to be necessary, increased emphasis should be laid on non-structural measures such as flood forecasting and warning, flood plain zoning and flood proofing for the minimisation of losses and to reduce the recurring expenditure on flood relief.
• There should be strict regulation of settlements and economic activity in the flood plain zones along with flood proofing, to minimise the loss of life and property on account of floods.
• The flood forecasting activities should be modernised, value added and extended to other uncovered areas. Inflow forecasting to reservoirs should be instituted for their effective regulation
Drought
Drought is widespread in India. It is primarily a deficiency in rainfall but over exploitation of ground water aggravates the situation.
Large evaporation resulting from poor water retention capacity of soil adds to the problem. It is also the result of poor water management strategy, deforestation and indiscriminate industrial exploitation of water resources.
Human or social factors often aggravate the effects of drought. Depletion of forest, overgrazing, soil erosion, extension of cultivation to marginal lands and lowering of water level etc. directly contribute to and aggravate the ill effects of drought.
When the monsoon rainfall deficit for the country as a whole is 10% below normal or worse, and 20% or more area of the country, suffers from rail1 deficit, it is reckoned as a "drought year" for the country as a whole.
Cyclone
Cyclones are characterized by very strong winds, torrential rains and associated floods which cause extensive damage to human lives and property in the coastal areas. India has a very long coastline of 7517 km, a major portion of which is exposed to tropical cyclones arising in the Bay of Bengal and Arabian Sea. In India cyclones occur usually between April and May, and between October and December.
Suggestions: An effective cyclone disaster prevention and mitigation plan requires:
• efficient cyclone forecast - and warning services;
• rapid dissemination of warnings to the government agencies, particularly marine interests like ports, fisheries and shipping and to the general public and
• construction of cyclone shelters in vulnerable areas, a ready machinery for evacuation of people to safer areas and community preparedness at all levels to meet the exigencies.
Landslide
Among the natural hazards that strike the mountainous areas almost perennially, landslips occupy a position of major concern. The Himalayan range constitutes a young and therefore a fragile mountain system. The Himalayas in general are fragile in nature due to tectonically displaced and folded as well as crumpled rock formation and due to periodic earth tremors ill this belt.
Causes of Landslides
A slope may yield a wide variety of mass movements. Slope failures are normally due to sheer stresses which increase with the inclination and height of & slope and occur when sheer stress exceeds the sheer strength. When the forces of equilibrium alter marginally the landslide is slow and if the disturbing forces undergo significant change, the movement of mass is fast. The rock fall, and debris flow in Himalayas are caused due to heavy precipitation and saturation during rainy season and consequent development of hydrostatic.
Suggestions:
These can be classified into structural and non-structural measures: Structural measures:
Planting (Avalanche Prevention Forest)
Stepped Terraces
Avalanche Control Piles
Avalanche Control Fence
Suspended Fences
Snow Cornice Control Structures
Protection structures such as stopping, deflecting and retarding structures.
Non-structural measures - removing snow deposits on slopes by blasting, predicting avalanches and evacuating people from vulnerable areas.
Tsunami
Tsunamis are large waves generated by sudden movements of the ocean floor that displace a large volume of water. Although usually associated with earthquakes, tsunamis can also be triggered by other phenomena like submarine or terrestrial landslides, volcanic eruptions, explosions or even bolide (e.g. asteroid, meteor and comet) impacts. Tsunamis have the potential to strip beaches, uproot plantations, and inundate large inland tracts and extensively damage life and property in coastal areas. The Indian coastal belt had not recorded many tsunamis in the past.
The phenomenon of tsunami that usually occurs near seismically active spots in the Pacific Ocean was uncommon in India till it hit the east and west coast in December 2004. The waves damaged the life and property in the coastal areas of Andhra Pradesh, Tamil Nadu, Pondicherry, Kerala and Andaman and Nicobar Islands as never before.
What is a Disaster
Disaster is an undesirable occurrence resulting from forces that are largely outside human control, strikes quickly with little or no warning, which causes or threatens serious disruption of life and property including death and injury to a large number of people, and requires therefore, mobilisation of efforts in excess of that which are normally provided by statutory emergency services.
Definition for Indian official purposes: Disaster means a catastrophe, mishap, calamity or grave occurrence in any area, arising from natural or man-made causes, or by accident or negligence which results in substantial loss of life or human suffering or damage to, and destruction of, property, or damage to, or degradation of, environment, and is of such a nature or magnitude as to be beyond the coping capacity of the community of the affected area
Disaster is assessed on the basis of the following features:
• Disruption to normal pattern of life. Such disruption is usually severe and may also be sudden, unexpected and widespread.
• Human effects such as loss of life, livelihood and property, injury, hardship and adverse effects on health
• Effects on Social Structure such as destruction of or damage to infrastructure, buildings, communications and other essential services.
• Community needs such as shelter, food, clothing, medical assistance and social care.
AGGRAVATING FACTORS OF DISASTERS
Poverty
All disaster studies show that the wealthy among the population are less affected and also able to recover quickly. However, poverty generally makes people more vulnerable to all the impacts of disasters. It is only due to poverty that poor people are forced to live in more vulnerable areas such as flood plains of rivers.
Population Growth
If there are more people and structures where a disaster strikes, there will be more impact. Increasing number of people will compete for limited resources (e.g., employment opportunities) which can lead to crisis-induced migration. This aggravates the disasters in developing countries.
Rapid Urbanisation
Rapid and unplanned urbanisations make the poor people to live at unsafe places and with least resources at their disposal. Many of the landslides or flood disasters are closely linked to rapid and unchecked urbanisation which forces low-income families to settle on the slopes of steep hillsides or banks of rivers.
Transitions in Social Practices
All societies are under a continual state of transition which is often disruptive and uneven, leaving gaps in social coping mechanisms and available technology. These transitions include nomadic population that become sedentary, rural people who move to urban areas, and both rural and urban people who move from one economic level to another.
Environmental Degradation
Many disasters are either caused or aggravated by environmental degradation. Deforestation leads to rapid rain runoff, which contributes to soil erosion and flooding.
Lack of Awareness and Information
Lack of awareness and proper information usually converts a hazard into a Disaster. This ignorance may not necessary be due to poverty, but due to a lack of awareness of what measures can be taken to build safe structures on safe locations.
War and Civil Strife
War and civil strife are regarded as hazards, that is, extreme events that produce disasters. The causal factors of war and civil strife include competition for scarce resources, religious to ethnic intolerance and ideological difference.
KEY DISASTERS IN INDIA
Earthquake
Earthquakes are considered to be one of the most dangerous and destructive natural hazards. The impact of this phenomenon is sudden with little or no warning, making it just impossible to predict it.
Therefore, the best strategy is to make preparations against damages and collapses of building and other man-made structures, About 50-60% of total area of the country is vulnerable to seismic activity of varying damage potential. Most of the vulnerable areas are generally located in Himalayan and sub-Himalayan regions extending from Kashmir to Arunachal Pradesh, Kutch and in Andaman and Nicobar Islands.
Suggestions: In our present state of knowledge, earthquakes can neither be prevented nor predicted in terms of their magnitude, or place and time of occurrence.
Therefore, the most effective measures of risk reduction are pre-disaster mitigation, preparedness and preventive measures for reducing the vulnerability of the built environment combined with expeditious and effective rescue and relief actions immediately after the occurrence of the earthquake.
Floods
Floods occur when large volume of water from heavy rainfall and/or river spill is not able to drain off quickly through normal channels.
India is the second most flood affected country where flood is a common natural disaster especially during the later part of the monsoon period. In India the most affected states due to floods are Bihar, Uttar Pradesh, North-Eastern states, Odisha & West Bengal etc.
The effects of flood on the affected population are manifested in the form of inundation marooning, drowning, loss of habitat roads, communications, destruction of crops, industrial shutdown, loss of wages, diarrhoea diseases, respiratory infections etc.
Causes of Floods
Inadequate capacity within the banks or the river to contain high flows,
River bank erosion and silting of river beds,
Landslides leading to obstruction of flow and change of the river course,
Synchronization of floods in the main and tributary rivers,
Retardation of flow due to tidal and backwater effects,
Poor natural drainage,
Cyclones and storm surge,
Cloud burst and flash floods.
Suggestions
• There should be a master plan for flood control and management for each flood prone basin.
• Adequate flood-cushion should be provided in water storage projects, wherever feasible, to facilitate better flood management.
In highly flood prone areas, flood control should be given overriding consideration in reservoir regulation policy even at the cost of sacrificing some irrigation or power benefits.
• While physical flood protection works like embankments and dykes will continue to be necessary, increased emphasis should be laid on non-structural measures such as flood forecasting and warning, flood plain zoning and flood proofing for the minimisation of losses and to reduce the recurring expenditure on flood relief.
• There should be strict regulation of settlements and economic activity in the flood plain zones along with flood proofing, to minimise the loss of life and property on account of floods.
• The flood forecasting activities should be modernised, value added and extended to other uncovered areas. Inflow forecasting to reservoirs should be instituted for their effective regulation
Drought
Drought is widespread in India. It is primarily a deficiency in rainfall but over exploitation of ground water aggravates the situation.
Large evaporation resulting from poor water retention capacity of soil adds to the problem. It is also the result of poor water management strategy, deforestation and indiscriminate industrial exploitation of water resources.
Human or social factors often aggravate the effects of drought. Depletion of forest, overgrazing, soil erosion, extension of cultivation to marginal lands and lowering of water level etc. directly contribute to and aggravate the ill effects of drought.
When the monsoon rainfall deficit for the country as a whole is 10% below normal or worse, and 20% or more area of the country, suffers from rail1 deficit, it is reckoned as a "drought year" for the country as a whole.
Cyclone
Cyclones are characterized by very strong winds, torrential rains and associated floods which cause extensive damage to human lives and property in the coastal areas. India has a very long coastline of 7517 km, a major portion of which is exposed to tropical cyclones arising in the Bay of Bengal and Arabian Sea. In India cyclones occur usually between April and May, and between October and December.
Suggestions: An effective cyclone disaster prevention and mitigation plan requires:
• efficient cyclone forecast - and warning services;
• rapid dissemination of warnings to the government agencies, particularly marine interests like ports, fisheries and shipping and to the general public and
• construction of cyclone shelters in vulnerable areas, a ready machinery for evacuation of people to safer areas and community preparedness at all levels to meet the exigencies.
Landslide
Among the natural hazards that strike the mountainous areas almost perennially, landslips occupy a position of major concern. The Himalayan range constitutes a young and therefore a fragile mountain system. The Himalayas in general are fragile in nature due to tectonically displaced and folded as well as crumpled rock formation and due to periodic earth tremors ill this belt.
Causes of Landslides
A slope may yield a wide variety of mass movements. Slope failures are normally due to sheer stresses which increase with the inclination and height of & slope and occur when sheer stress exceeds the sheer strength. When the forces of equilibrium alter marginally the landslide is slow and if the disturbing forces undergo significant change, the movement of mass is fast. The rock fall, and debris flow in Himalayas are caused due to heavy precipitation and saturation during rainy season and consequent development of hydrostatic.
Suggestions:
These can be classified into structural and non-structural measures: Structural measures:
Planting (Avalanche Prevention Forest)
Stepped Terraces
Avalanche Control Piles
Avalanche Control Fence
Suspended Fences
Snow Cornice Control Structures
Protection structures such as stopping, deflecting and retarding structures.
Non-structural measures - removing snow deposits on slopes by blasting, predicting avalanches and evacuating people from vulnerable areas.
Tsunami
Tsunamis are large waves generated by sudden movements of the ocean floor that displace a large volume of water. Although usually associated with earthquakes, tsunamis can also be triggered by other phenomena like submarine or terrestrial landslides, volcanic eruptions, explosions or even bolide (e.g. asteroid, meteor and comet) impacts. Tsunamis have the potential to strip beaches, uproot plantations, and inundate large inland tracts and extensively damage life and property in coastal areas. The Indian coastal belt had not recorded many tsunamis in the past.
The phenomenon of tsunami that usually occurs near seismically active spots in the Pacific Ocean was uncommon in India till it hit the east and west coast in December 2004. The waves damaged the life and property in the coastal areas of Andhra Pradesh, Tamil Nadu, Pondicherry, Kerala and Andaman and Nicobar Islands as never before.
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