GIS Development Staff
The low-income countries of South Asia accommodate a large population of over a billion. The sustained efforts for economic growth of those countries are often interrupted by recurrent natural disasters with considerable impact exacerbating poverty conditions in different parts of the region.
Since times of unrecorded history South Asian countries have been facing the onslaught of natural disasters such as floods, cyclones, earthquakes, landslides, etc. The intensity of those disasters differs due to spatio-temporal variations of the physiographic and climatic conditions. The low-income countries of South Asia i.e. Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka accommodate a large population of over a billion. The sustained efforts for economic growth of these countries are often interrupted by recurrent natural disasters with considerable impact exacerbating poverty conditions in different parts of the region. In this article an effort has been made to focus on some major disasters in those countries along with some measures taken for managing those disasters.
Bangladesh is prone to several kinds of natural disasters among which tropical cyclones with associated storm-surges, floods, droughts, tornadoes, and riverbank erosions are most active and frequent. Besides, the occurrences of earthquakes at times make significant impact both on social life and topography of the country.
Floods of different types in Bangladesh are a complex phenomenon. Flash floods suddenly rise and fall rapidly. At much longer intervals(perhaps 20 years or more) flash floods overwhelm almost the whole landscape in northern part of the country as they did in 1968 and 1987. At an average time interval of about 3 to 4 years riverfloods extend beyond the active floodplains and damage crops on parts of the adjoining meander floodplains, mainly alongside distributary channels. The severe floods which attracted international attention are in 1974, 1977, 1980, 1984, 1988, 1998 and of many earlier years. In August-September, 1988, Bangladesh experienced an unprecedented flood causing loss of 1621 human lives and again during July-September, 1998 the country experienced another flood which is the worst in the living memory both in respect of its long duration and water level. Almost two-third area of the country was inundated causing widespread damage to the economy of the country ever before.
The 1994 flood was followed by a famine which, according to the official record, caused 30,000 deaths. Droughts seriously reduced crop production in 1972, 1978-79, 1982 and 1989. As it located adjacent to the Bay of Bengal, it has the worst record of tropical cyclones (typhoons) and storm surges in the world. The cyclone disasters of 1970 (300,000 dead) and 1991 (138,000 dead) are among the worst disasters in the world. Tornadoes caused localised devastation demanding immediate response. A severe tornado hit Tangail district of the country on the 13th May, 1996 causing 540 death and injuring about 34,000 people.
As per the recorded history Bangladesh also has potentiality for earthquake hazards. The country as a whole lies in the earthquake zone, of which two-third comes under major and moderate fault. On the 21st November, 1997 an earthquake with an intensity of 6.1 on Richter Scale occurred affecting the entire Chittagong region, the jolt of which was felt up to Dhaka. Beside all these another major disaster in this country is riverbank erosion along the courses of the mighty rivers like Yamuna, Meghna etc. Every year, erosion takes away chunks of land causing displacement of large number of people and losses of properties.
In Bangladesh advance mapping technologies are being utilised for disaster management. In a particular study in Bangladesh, as mentioned by Cees J van Westen in his article in ITC Journal, GIS with digital image processing and analysis of sequential SPOT images for flood stage mapping was carried out. The study area covers the confluence of the Meghna and Ganges rivers, south east of the capital of Dhaka. The SPOT images were used in the study to assess the spatial distribution of the inundation (flood stage mapping)and river dynamics (changes in channel and channel pattern).
Bhutan, covering southern foothills rising from the Indian plains, the northern high Himalayas bordering the Tibetan Plateau and the central valleys of the inner Himalayas, is relatively free from major natural hazards like cyclones, droughts and earthquakes. Sometimes flash floods and landslides pose some problems.
As the economic impact of disasters is confined to localised areas and does not cause major disturbances the assessments of the natural hazards do not figure prominently in the development programmes. Bhutan has no seismic station or observatory. Slope stability studies are carried out by the National Geoscience Organisation. A hydro-meteorological network is there with 110 stations and 23 gauging stations located in rivers and their tributaries. Since there is no specific natural hazard identified to be a serious threat, there are no warning systems.
In India, records show that the number of natural disasters is increasing covering new areas year after year. Almost all types of natural hazards affect different parts of the country. In this context, we may remember the recent earthquake of Dharmsala (1986), north-east part of India (1988), Bihar-Nepal (1988), Uttarkashi (1991), Latur (1993), cyclone of Andhra Pradesh (Nov.96), landslide of Malpa (1998), severe droughts which occurred consecutively for two years (1904-05, 1965-66 and 1986-87) and floods in the Indo-Gangetic plains in almost each and every year etc.
The National Agricultural Drought Assessment and Management System (NADAMS) is developed by Department of Space for Department of Agriculture and Cooperation, and is primarily based on monitoring of vegetation status through NOAA (National Oceanic and Atmospheric Administration) AVHRR (Advanced Very High Resolution Radiometer) data. Availability of ERS-I SAR data has helped flood mapping. Multiple Landsat-TM, shortwave-IR bands, with data of both day and night passes have already been used to study a number of forest fires and to monitor the vegetation regeneration over burnt areas. The national system INSAT provides the capability for rapid communication, data collection and providing support to carry out relief operation.
The Republic of Maldives consisting of 26 atolls with 1190 islands is free from the hazards like earthquakes, floods and cyclones. Sometimes high waves and storms cause damage of some areas. Fire hazards also occur. No national organisational structure is there for disaster management. The country has had a Committee on Natural Disasters since mid 1980s. The Meteorological Department arranges to broadcast warnings about adverse weather conditions.
The effectiveness of disaster response needs to be strengthened through better management skills, higher level of coordination and involvement of all concerned. It should also be remembered that the application of science and technology to reduce and manage disaster needs to be considerably stepped up through measures aimed at promoting research and strengthening institutional capabilities for technology development, education and training.
Nepal, which is drained by more than 6000 big and small rivers usually has to face flood hazard. As about three-fourth of annual surface run-off occurs during the monsoon period, these, when de-bouncing into plains, cause immense damage in the “terai” plains of Nepal and India. Again, sometimes flooding in hilly valleys occurs due to cloud bursts and resulting incessant rains, causing landslides which usually block the river course. Such events which rarely give enough warning time to enable preparedness, had occurred frequently in recent decades. The glacial lakes outburst flood (GLOF) of 1985 in the Kosi river caused unprecedented devastation and completely swept off the nearly completed Namch-hydropower plant, leaving no trace of it, besides damaging roads, bridges, houses etc.
Because of the location of the country in a region of high seismic activity earthquakes with magnitudes of 5 to 8 on the Richter scale have been experienced throughout the country and 279 earthquakes with epicentres in Nepal and magnitudes above 3.9 were recorded during 1963-86. Major recent earthquakes include those of 1980 and 1988.
A significant number of landslides also occur each year, perhaps as many as 12,000. Based on available land resource and land use data, about 13 per cent of the total area of Chura and mid-hilly region of the country suffers from the effects of landslides. Various natural and man-made factors contribute to the high incidents of landslides. Natural factors include steep slopes; undercutting of their banks by incised rivers; weathered, fractured and weak rocks in the mountains; high rainfall; and seismic activity. Human interference with the fragile ecosystem aggravates this situation.
Pakistan, a country with varied geographical features, is susceptible to earthquakes, landslides, droughts and floods. It has a long history of earthquake. In 1935, the Quetta earthquake killed 35,000 people. Since 1947, the country has faced eight major droughts and six major floods. The major flood years were 1972, 1976, 1985, 1986, 1988 and 1992.
For the implementation of relief and rehabilitation programmes a National Disaster Plan was prepared in 1974. An institutional arrangement at the provincial, divisional, district and sub-district level exists for emergency management. A flood warning system has been established by the Water and Power Development Authority (WAPDA) with 41 telemetric gadgets at key river locations for collecting river discharge data. The data collected by WAPDA through the radar at Sialkot, and the information furnished by the Indian authorities, are used to prepare computerised rainfall run-off and also for flood forecasting.
Sri Lanka, the another country in the south Asian region usually suffers a lot from various types of disaster such as flood, landslides, drought, cyclone etc. As per the available records, flood is the most common natural disaster which has occurred in each and every year since 1981 to 1996 along with another disaster i.e. landslides. Droughts are almost very frequent cyclones occurred in 1993, 94, 95 and in 1996 which affected a number of families. The western part of the country is prone to floods. Droughts affect the northern and the eastern parts. The country is also prone to cyclones and coastal erosion. More than 600 kms of the coastal region is affected by sea erosion. There is increasing incidence of landslides in the central hilly region and the south-western region.
A study conducted by Telecommunication Regulatory Commission of Sri Lanka in association with International Telecommunication Union, United Nations Office for the Coordination of Humanitarian Affairs, Working Group on Emergency Telecommunications and ICO Global Communications represents a milestone in comprehensively and responsibly addressing the use of telecommunication resources in mitigating human sufferings due to disaster. Cooperation and co-ordination among the Administration, the Aid Organisation, the Technical Community, the Service Provider and the general publics is indispensable in deploying telecommunication resources for the prevention and mitigation of disaster. Telecommunication can link between the disaster stricken area and the rest of the world including the authorities, the relief organisation, scientific community and media.
The post disaster activities of the Department of Social Services, as mentioned by N. J. Pathirana (1998) shows that there is a chain of command in disaster relief activities in respect of natural disasters. The key information comes from the target groups or victims to Grama Niladaries, from Grama Niladaries to Divisional Secretariat and from Divisional Secretariat to District Secretariat. These information are then sent to the Central Government through the Department of Social Services and Ministry of Social Services.
The directives and funds are provided to Divisional Secretariat and District Secretariat through the Department of Social Services which receives the same from the Central Government through the Ministry of Social Services. Some International Organisations provide funds for disaster relief activities, it is received by the Department of Social Services. In this well-equipped network some information centres also work side by side which send key information to the Department of Social Services and receives directives, funds and assistance in lieu.
Disaster telecommunication which might be very much helpful for disaster management has to face some problems. Some of the problems are institutional such as different awareness, problem of inter-agency cooperation –coordination etc. Some regulatory problems like lack of legislation, lack of clear custom clearance, delay in approval process, heavy custom duties etc. are also there. On the other hand, some technical and financial problems also hinder the proper functioning of the telecommunication network in Sri Lanka.
Mapping for Disaster Management
Risk assessment in Nepal has not been undertaken on a systematic basis although there is some degree of general risk awareness among the people and the planners. The Remote Sensing Project as a part of Risk Assessment through hazard mapping in Nepal has mapped natural resources such as forests, water and land resources. Detailed land resources mapping has been carried out by the Land Resource Mapping Project. Aerial photography and satellite imageries have been employed for mapping purpose, but those maps do not incorporate mapping of natural hazards.
The Department of Mines and Geology has produced maps showing the geographical distribution of past earthquakes, but microseismic maps do not exist. The department has given priority to the study of landslide activities with the assistance of the Federal Institute of Geo-science.
The Natural Calamity Relief Act (1982) established the Central Disaster Relief Committee (CDRC) as the highest body responsible for disaster administration. It is mainly responsible for relief and disaster preparedness. Disaster-related studies are also undertaken by institutions like the International Centre for Integrated Mountain Development (ICIMOD) in Kathmandu. ICIMOD has studied glacial lake outbursts, landslides and risk engineering in the Himalayas. Organisations like the Royal Nepal Academy for Science and Technology (RONAST) and the King Mahendra Trust for Nature Conservation (KMTNC) are also working in the field, focussing on environmental protection and conservation.
Nicholas Russell, Madhu Rahman Acharya and Shree Ram Pant proposed future actions required in the field of disaster management such as, preparation of hazard maps identifying hazard areas, zoning of risk areas, establishment of a single disaster management organisation, creating a permanent training institute for training of trainers and disaster managers, formulating standard codes of engineering practice and building codes, applying structural mitigation to major projects and infrastructure, undertaking by a Kathmandu Valley Earthquake Study encompassing vulnerability of infrastructure, developing communication (physical) network throughout the country, developing mechanism for establishing a regional database, sharing and using satellite and image processing facilities through the regional space laboratory, setting up the procedures and guidelines for disaster mitigation management.
- Brammer, Hugh and Khan, Hamidur Rahman (1991), Bangladesh Country Study, Disaster Mitigation in Asia and Pacific, Asian Development Bank, Philippines.
- Jain, N. K. Floods in South Asian Context – A Critical Review.
- Islam, Md. Shamsul (1999), Disaster Management System in Bangladesh, Lecture notes, the 24th Disaster Management Course of Asian Disaster Preparedness Centre (ADPC), Bangkok.
- Natural Disaster Reduction, South Asian Regional Report, presented to the World Conference on IDNDR, Yokohama, Japan, May 23-27, 1994.
- Ratnayake, Jagat, Interim Report of the Pilot Study on the Use of Telecommunications in Disasters and Emergency Situations in Sri Lanka.
- Russel, N., Acharya, M. R. and Pant, S. R. (1991), Nepal Country Study, Disaster Mitigation in Asia and the Pacific, Asian Development Bank, Philippines.
- Westen, C.J.V., Remote Sensing and Geographic Information Systems for Geologic Hazard Mitigation, ITC Journal 1993-’94.