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close this bookNatural Disasters in South East Asia and Bangladesh - Vulnerability Risks and Consequences (Centre for Research on the Epidemiology of Disasters - International Center for Training Exchanges in the Geosciences, 1998, 83 p.)
close this folder1. Criteria used to identify territories prone to risks
View the document(introduction...)
View the document1.1. Hazards
View the document1.2. Different population types and consequences as concerns vulnerability


Both the criteria concerning the types of dangers and those of the population types are considered. These data, together, enable the identification of the different types of territories prone to risks.

1.1. Hazards

Other than volcanism (the Philippines) and the effects due to earthquakes (the Philippines, Bangladesh, Myanmar and Vietnam) there are 8 hazards (see key for the maps of the territories prone to risks). As mentioned above, floods and cyclones are the most dominant. Floods are subdivided into river floods, which have an annual frequency because of the effects of the monsoon winds, and flash floods of the mountain rivers

Cyclones affect preferably coasts, deltas, coastal plains but also the mountains exposed to winds such as the Annamitic mountain chain in Vietnam, the Arakan Yoma mountains in Bangladesh and Myanmar which will be called coastal mountains.

Floods related to great rivers affect deltas and inland basins. The latter often protected from high intensity cyclones by coastal mountains are not sheltered from droughts because they are practically exposed to wind (Mekong Laotian plains, Menam Chao Phraya and Irraouadi middle basins). The same is true for inland mountains which are preferentially affected by mud slides, landslides and flash floods.

Storm surges and high tides may increase the effects of the annual floods or the floods associated with cyclones in coastal plains and deltas to which one can add the subsidence of deltas. For example the meteorological department in Thailand reported that in 1996 "continuing floods due to high tides remained in several locations of the lower central" (terminal part of the Chao Phraya delta) "especially along the Chao Phraya River banks until November" (13).

13 In: Damage caused by floods, drought, tropical cyclones and other severe weather events in Asia and the Pacific during 1996. Water Res. Journ., June 1997, p. 3

In drawing up an assessment (cf. key to maps of territories prone to risks) it has been possible to identify five national sub-types areas associating, though unequally, the different types of dangers. It is also possible to regroup deltas and coastal plains on one side, and both inland and coastal mountains on the other, the inland basins being notably different from the two preceding groups.

The interest of this approach lies in the fact that the national sub-types groupings correspond to human groups that are also differentiated, and therefore enables the identification of the different types of territories prone to risks.

1.2. Different population types and consequences as concerns vulnerability

Two types of central areas (centres) and three types of peripheral areas (margins) can be distinguished. This depends on the establishment of national territories and their present development.

* Central areas

The two types of centres concern the inland basins and the deltas. The countries have been constituted either around inland fluvial basins or from the head of a delta. This has been revealed by the downstream historical displacement tendencies of the capitals. This is the case for Burma (Mandalay and Rangoon), Thailand (Ayutthaya-Bangkok), and Laos (Louang Phrabang-Vientiane). The capitals are in the inland and associated to the principal rivers; Dhaka is situated 200 km from the Bay of Bengal on the Burhiganga river, which name evokes a sacred river; Bangkok lies along the Menam Chao Phraya which means "mother water" (DE KONINCK, 1994, p. 231); Hanoi is 100 km away from the sea, but indirectly associated to the Red River and its delta. At last, the Royal palace of Phnom Penh "lies at the exact confluence of the Mekong and Tonle Sap rivers where, twice a year, the latter reverses its course" as a result of the Mekong floods (DE KONINCK, 1994, p. 266).

Historically, the roots of this part of Indochina underline the great significance of the attachment to land and fluvial waters. The successive migrations that constituted the populations in question, apart from the Philippines, came principally from South China. They got to Indochina by simply going down the valleys of the major rivers. The centres today are therefore composed of one or several inland fluvial basins and their deltas associated to their agrarian cities. The populations involved in foreign trade, particularly the Chinese, unequally transformed these cities. Apart from Laos and the Philippines, the current capitals are found in the deltas which are characterised by a concentration of international investments. Inland basins and deltas are particularly populated by the dominant ethnic group in power.

The consequences of all that has been mentioned above, for these two types of central territories, tend to increase the vulnerability to the various risks for two reasons:

- On one hand, the physical dangers, particularly in the deltas, often have a high frequency and intensity yet there is an obvious increase in the activities and infrastructures in the different capitals despite the strong disparities from one country to another. The international openings, logically, promote the urban growth (PIGEON, 1994) but they also favour the vulnerability for a number of reasons.

First of all it is because of the growing pre-eminence of the "commercial" districts over the "agrarian" ones (CLEMENT-CHARPENTIER, 1995). This signifies an increase in the population density in areas close to water bodies where, historically, the minority trader communities are found, among which the Chinese communities. Then the same evolution as observed in Bangkok takes place. Historically, the Thai people are known to have used canals (khlongs) as a means of transport but people from the Western countries who lived in the South closer to the sea supposedly had the first street built in 1861. This street was rapidly occupied by the Chinese "compartments" (14) (CLEMENT-CHARPENTIER, 1995, p. 115).

14 Buildings used for both commercial and dwelling purposes.

This development leads to and favours the filling of the canals, which plays a role in the floodings that affect the Thailand capital.

Moreover, the river dikes are weakened by the heavy construction of buildings close to the rivers. This was observed in 1995 at Hanoi by DRAKAKIS-SMITH & DIXON (1997) who stated: "recently, in Hanoi, uncontrolled buildings within the restricted limits adjacent to one of the city's main dykes was blamed for serious cracks appearing in this major flood control measure. Typically, instead of total demolition, only construction within 5 metres of the dyke was demolished, leaving some houses without any fronts, and even this was bitterly contested by private investors".

At last the spreading of urbanization in the delta tends to destroy the community relationships, does not encourage traditional agricultural activities, and partly explains the degradation of dykes, canals, which also play a major role in flood management.

On the other hand, the cultural heritages tend to aggravate this vulnerability by minimizing the damages related notably to floods. In these societies, except in the Philippines, farmers dominate. Therefore they have been led to manage water, (maybe because of physical constraints since the inland basins are principally sheltered from the monsoon winds) and have obviously a particular, ambiguous, approach of the effects of floods on which agriculture depends fundamentally.

In Bangladesh local populations refuse flood disappearance: "the majority of the practising farmers were against the idea of preventing flooding entirely, perhaps because of the way they adjusted their agricultural practices to normal flood regimes" (RASIN & MALLIK, 1995). Even more, "these authors indirectly state that the farmers were not totally surprised by the exceptional floods of 1987. On one hand they were able to empirically predict the occurrence of a more intense flood ("As heavy monsoon rainfall coincided with such rapidly rising river levels, many farmers could predict the impending high-magnitude flood"). On the other hand, they developed at least 19 different techniques in order to minimize crop damages which makes the exceptional aspect of the flood relative, as it was experienced by the local populations and despite the importance of both human and material damages. In Thailand, awakening to the environment-related problems is not so much linked than to floods as to possible droughts like the one that occurred in 1994 (RIGG, 1995): 'Perhaps, it is this ancient link between water, happiness and prosperity which accounts for the fervent discussion which has accompanied Thailand's most recent water crisis". Finally, the Khmers adapted their way of life to seasonal floods of the Tonle Sap thanks to pile-dwelling, or even floating houses.

This therefore underlines the relativity of perception of risks, if not disasters, by the local populations despite the significance of the damages in case of floods with intensities above the mean values. This fact should be taken into account in order to interpret the relatively few statistics concerning the countries like Laos and Cambodia. It reveals the limits of a purely technical response to the risks of flooding in a country like Bangladesh, as mentioned by THOMPSON and SULTANA (1996).

* The outlying areas

Mountainous and coastal peripheral areas are in complete contrast to centre areas and fluvial basins.

It is in the mountains that one can find the minority ethnic groups, called the tribal groups, who generally practice agriculture considered as less intensive, are of different religions and speak differently. In Laos, the Lao majority represents only 55% of the population but is concentrated in the Mekong plains. These Lao Lum (low Laos), Buddhists, differ from the Laos Soung (Laos of the summits) who arrived last from China and are animists.

The contrasts are often strong between the summit populations where shifting agriculture is practised and the populations living in the valleys, where it is possible to find a more intensive agriculture. For example this is the case in the north of Thailand.

The coasts have been, historically, considered as areas of little interest which is manifested in the population aspects and distribution. The city of Rangoon in Burma is an ancient Mort that was partially transformed into a garrison by the Burmese, and developed by the British, so much so, that the present Burmese in Rangoon "have never seen the sea" (LUBEIGT, 1997, p. 27). The Bengal coast proves to be associated to real pioneer fronts, such is the case with the Thailand "Eastern Seaboard Development Programme". In Vietnam, despite the anteriority of the Khmer presence, the Saigon area (Ho Chi Minh-city), though associated to the Mekong delta, "provided but a base for a wharf and a fort" at the time when the Vietnamese took over the city in the 17 century (DE KONINCK, 1994). However, at 200 km north-west, the significance is known of the angkorian vestiges around the Mekong and Tonle Sap valleys just upstream of the apex to the delta and in a territory that continually attracted the greed of the Vietnamese.

As a matter of fact, the opposition between the centres and the outlying areas favours a definite trend in political instability, be it in the framework of both civil or international wars. Tensions divide the dominant ethnic groups from the "tribal" ones, but also the dominant groups amongst themselves. The international powers have not hesitated to capitalize on these structural weaknesses within the framework of colonial policies or the rivalry between the United States of America, ex-USSR and China. The historical heritages are heavy, the suspicious attitude of these peoples in front of their neighbours persists. At last, everybody knows how much the badly controlled borders promoted all kind of illicit trading, in particular, in the famous gold triangle.

There again, the consequences of this tends to increase the vulnerability in view of risks.

Risk management is obviously influenced by this partition of the population types. The vulnerability of the major populations and that of the marginal ones does not have the same significance in that the Governments will be even less inclined to intervene in order to handle the risks concerning the populations often considered inferior and badly assimilated. But these populations are one of the poorest in the country and show, from estimations, high illiteracy rates; they are, yet, established in the mountains or associated to the coasts in the areas where the hazards generally have higher intensities and frequencies. It is clear that cyclones and earthquake induced effects (tsunamis for example) hit the coastal areas and the Arakan Yoma mountains open to the Bay of Bengal more than the centre of Bangladesh or that of Burma. These areas are, yet, very difficult to get to by road and the Ngapali station, on the Arakan coast, is served by aeroplane on a daily basis only in the dry season (LUBEIGT, 1997, p. 37). These are also areas which are not under the central governmental control at the time when the effects induced by deforestation are being denounced with lots of ulterior geopolitical motives. The Lao News (April-June 1997) reported that "planning the eradication of slash-and-burn practices: in the Lao P.D.R, shifting cultivation is causing an alarming amount of forest destruction. According to the government's plan for the stabilization of slash-and-burn cultivation, it will try to resettle about 100,000 swidden families by the year 2000".

But at the same time, an increased political will has been observed as regards opening-up to international trade, which induces to develop infrastructures and to increase the human presence in these marginal areas. The international opening-up is wished not only by the Chinese diaspora and the former colonial powers but also by central governments. It therefore seems to be following the development desired by Thailand and particularly China since the Open-door policy of 1979. It is worth recalling that Vietnam changed its attitude in relation to international investments by the so-called "doi moi" policies in 1986 (DRAKAKIS-SMITH & DIXON, 1997), and joined the ASEAN in 1995. In November 1996, Laos, Cambodia and Burma were accepted into the ASEAN, this admission being effective from July 1997 (Lao News, July 1997). The year 1996 was declared by Burma as the year of tourism. Some international development projects appear such as the gold quadrilateral "intended to increase trade within the highlands adjacent to Laos, Chinese Yunnan, Thailand and Burma" (DE KONINCK, 1994).

The consequences as far as vulnerability is concerned are numerous. These plans show a renewed interest for the mountainous valleys of the principal rivers which may regain their privileged main-live function of trade with China, their historical function (TAILLARD, 1989). This gave rise to the railway projects in Laos. In February 1997, the Laotian government authorized a joint-venture agreement with a company called "Pacific Transport Company" whose aim was to make a train pass over the Friendship Bridge and extend the section to Louang Phrabang then to China. The April 1997 bulletin of the Lao News adds: "in addition to the construction of railways, the agreement talks about other projects, including developing industrial zones". The increased international opening-up also shows a renewed interest for the coasts, on which shrimp breeding for export and also touristic infrastructures are found very unequally distributed depending on the country (Bangladesh, Burma). Within such physical frameworks, the increase in land value means, inevitably, an increase in the vulnerability and suggests an interest to associate preventive measures against certain physical hazards to economic development.

The above considerations allow the identification and justification of five territories prone to risks.