Specific Hazards and Mitigation
Hazards and disaster are very closely related and are sometimes taken as synonymous. As compared to natural hazards, natural disasters are relatively sudden and cause large scale death and loss of property.
Mitigation is the effort to reduce loss of life and property by lessening the impact of disasters. Mitigation efforts help the people by creating safer communities and reducing loss of life and property. It can take place before, during or after a disaster. It lessens the financial impact of disasters on government and communities. Mitigation strategies can be categorises as structural and non structural.
Flood is a general and temporary condition where two or more acres of normally dry land or two or more properties are inundated by water or mudflow. Many conditions can result in a flood such as
• Excessive rainfall
• Poor natural drainage.
• Landslides leading to obstruction of flow and change in the river course.
• Cyclone and very intense rainfall when the El Nino effect is on a decline.
Structural measures for flood include water shed management, reservoirs, building on elevated area, construction and protection of embankments, ring bunds, etc. Non-structural mitigation include mapping of flood plains and land use control, etc.
Cyclone is a rapid inward circulation of air and refers to many different types of storms. Millions of people living in the coastal areas in India regularly face the hazards of cyclone. Among the mitigation measures sea walls, multi-purpose shelters, good construction practice, saline water embankments are most effective and capital intensive investment to mitigate the risks of cyclones.
Earthquake is a sudden onset hazard and can happen at any time. To reduce the impact of earthquakes, engineered structures should be designed and building codes should be enforced.
Landslides are a major natural disaster in hilly areas. Drainage correction, engineered structures, increasing vegetation cover, hazard mapping and awareness generation, etc., are major part of mitigation strategies.
Drought is a natural hazard, it has a slow onset, and it evolves over months or even years. water-use planning, rain-water harvesting, runoff collection using surface and underground structures, improved management of channels and wells, and dam construction, are implemented as a part of a drought-mitigation plan.