THE DISASTROUS FLOODS which struck Bangladesh in 1987 and 1988 killed more than 3,000 people. They destroyed millions of homes, devastated crops on several million hectares of land, killed over 200,000 farm animals and did enormous damage to the country's economic infrastructure. Direct capital losses were estimated at $1.8 billion. Indirect economic losses may have been even higher.
Not quantified was the enormous human distress. The 1988 flood submerged about two-thirds of the country, directly affecting some 45 million people, urban as well as rural. Many lived for weeks under appalling conditions, with inadequate shelter, food, water, sanitation and health care, without employment, and dependent on government and voluntary relief.
These successive disasters stimulated the international aid community to support the Government of Bangladesh in seeking a lasting solution to the country's chronic flood problem. Following a diverse range of preliminary studies, a Flood Action Plan (FAP) was prepared in 1989 and launched in 1990.
The FAP comprises 26 components. It is supported by 15 donors and is coordinated by the World Bank, at the request of the Government of Bangladesh. The cost of the first phase (1990-95) is about US$150 million. Local coordination is through the Flood Plan Coordination Organization (FPCO) set up under the Ministry of Irrigation, Water Development and Flood Control. FPCO is supported by international and local specialists, the so-called Panel of Experts.
The aims of the first five-year phase are:
Contrary to assumptions made by some of its critics, the FAP is not a construction plan. It mainly comprises studies and pilot projects which aim to identify the most appropriate flood mitigation measures, non-structural as well as structural, for different parts of the country. The objective is to identify projects for donor funding. Non-structural activities include the strengthening of existing flood warning, disaster management and hydrological modelling systems. Reviews have been made of the past performance of flood protection projects and of land acquisition procedures, how people responded to the 1988 floods, and means to flood-proof settlements, infrastructure and services.
A number of special environmental studies have been made, and a comprehensive study of floodplain fisheries is in progress. Guidelines on project economic assessment, environmental impact assessment and public participation have been prepared for FAP consultants. Projects have been assisted in obtaining topographical surveys, aerial photography and satellite imagery, and a Geographical Information System has been set up.
Structure-linked activities include feasibility and design studies for the rehabilitation of two major embankments. These are the Brahmaputra right embankment, frequently breached by river erosion, and the south-eastern section of the coastal embankment which had fallen into disrepair (and was subsequently virtually destroyed by the 1991 tropical cyclone before rehabilitation had started). Feasibility studies have also been carried out for works to protect Dhaka city against floods and several regional towns (including Chandpur) mainly against river erosion.
To date, three out of five regional planning studies have been completed. These have led to feasibility studies being made in three identified flood control project areas which are expected to proceed to detailed design in 1993. Ultimately, it is envisaged that the regional flood management plans will be integrated into the National Water Plan.
The FAP does not specifically address possible impacts of global warming. However, the Meghna Estuary subregional study, due to start in 1993, will examine the implications of a rising sea-level in that vulnerable area. Since all climate models forecast increased monsoon rainfall for the Bangladesh region as global warming develops, floods may become even more frequent and severe than at present in future decades. This will need to be taken into account in future FAP planning and modelling.
Except for urban areas, the FAP does not advocate total flood protection. For rural areas, the policy is that of `controlled flooding'. River embankments will be provided with regulators to allow the continuation of the `normal' flooding to which farmers are accustomed and which provides benefits to fisheries, soil fertility and navigation. The regulators would be closed to keep out unwanted high or untimely floods which cause damage. Secondary embankments behind main embankments would divide the protected area into compartments, enabling water flow across the land to be controlled. The objective is to give farmers a more secure environment for investment in crop production in the monsoon season.
The concept of controlled flooding is being tested on the compartmentalization pilot project (FAP20). It involves detailed hydrological modelling and intensive public consultation. The latter aims to ascertain people's needs, identify potential conflicts of interest between different groups (for example, farmers and fishermen who might want water on or off the land at different times) and develop institutional arrangements for local project management to the extent possible.
A major reason why some critics oppose the FAP is the poor record of performance of flood control projects implemented in the past.
About 6,000km of flood embankments already existed pre-FAP. Both sides of the Ganges and Teesta rivers are fully embanked. Most of the Brahmaputra right bank and about half of the left bank are also embanked, as well as substantial sections of the Padma (the combined Brahmaputra and Ganges) and Meghna rivers. So are many eastern rivers which are subject to flash floods from adjoining hill areas. In addition, several thousand kilometres of embankments exist around polders in the coastal zone. A number of inland areas have been also been empoldered, some of them provided with pump drainage.
While there have been some successes, such as the Chandpur Irrigation Project, there have been many partial or total project failures. The FAP12/13 studies found that, amongst many contributory factors, the main reasons for poor performance were:
The consequence has often been public cutting of embankments during floods, with substantial loss of benefits and even additional damage.
Attempts are being made under the FAP to strengthen consultation and public participation. This is not an easy task in a strongly hierarchical society, and it would be unrealistic to expect overnight success.
Also, the Government of Bangladesh has made environmental impact assessments (EIAs) mandatory for all new projects. But again, carrying out EIAs is not an easy task in a country where there is a dearth of factual ecological information and which has already been strongly impacted upon by dense human settlement and intensive land use.
One of the principles of environmental management adopted is that any people who might suffer adverse effects as a result of a project intervention should be adequately compensated.
An example being studied is that of people living on unstable alluvial islands (chars) in the main rivers. There is concern that such people might suffer from increased flood levels and channel instability if new embankments confine the main channel. It is impossible to resettle such people elsewhere. There is nowhere for them to go. (Ideally, they should not have been allowed to occupy such hazardous land in the first place.) One form of `compensation' being considered is flood proofing: for example, raising the level of homestead mounds, providing flood refuges, and strengthening community services. It is hoped that an NGO-led pilot project will get under way in 1993.
The single most expensive item (about US$40 million) in the FAP programme is the river training pilot project (FAP21/22). This aims to test methods of river training and bank defence on selected reaches of the Brahmaputra river. The active channel of this river is 10-15km wide. It is strongly braided, constantly creating new chars and washing other land away.
Historically, the Brahmaputra has shown a preferred tendency to erode its right bank, advancing westward at an average rate of about 100m a year. This erosion has destroyed about half of the 220km length of the Brahmaputra right embankment built in the 1960s, necessitating recurrent rebuilding of threatened or eroded sections. Encroaching onto long-settled farmland, this erosion causes great distress to established families who are rendered landless. Understandably, there is strong public pressure to halt this erosion.
This is not an easy task. The Brahmaputra is a formidable river. So are the Ganges, Meghna and other rivers which also suffer bank erosion. Mean peak flows of the Brahmaputra and Ganges rivers are 65,500 and 51,500 cubic metres per second respectively; peak flows in 1987/88 were 50 per cent higher than these levels. The rivers run through soft alluvial sediments, and can scour channels 30-50m deep. There is no suitable rock for making structures. The cost of building groynes and revetments is, therefore, very high.
One approach to be tested is that of selective intervention (such as closing off or dredging channels) to `steer' the river away from critical bank sections. The Chinese appear to have had some success with this technique on the Hwang Ho River.
Will the FAP succeed? It is too early yet to be certain, one way or the other. However, whether additional embankments are eventually built or not, considerable benefits should accrue from the greater technical knowledge acquired from the multidisciplinary studies and from new approaches in public participation, environmental impact assessment, flood proofing, and so on.
One has to ask, what is the alternative to flood protection in Bangladesh? The population, now over 110 million, is expected to double by around 2030. That population lives predominantly on the country's floodplains which occupy 80 per cent of the total area. Agriculture is the mainstay of the economy and seems likely to remain so.
Whilst significant increases in crop production have been achieved in recent decades through the expansion of dry-season irrigation, the potential for further expansion could be exhausted by the end of the century. Thereafter, further increments in food production to support the country's burgeoning population must come from production in the monsoon season. For that, protection from the risk of recurrent floods will be essential with or without global warming.
The FAP has a vital role to play in establishing sound technical, institutional and environmental procedures for flood mitigation and management for the long-term benefit of all the country's people. That is the rationale for the strong international donor support for the FAP.
Hugh Brammer, 37 Kingsway Court, Hove, E Sussex BN3 2LP, United Kingdom.
Published Issue 8, April 1993