An SOS From Dhaka
Every year, uncontrolled flooding in the Brahmaputra and Ganges river basins results in loss of life, damage to crops, dwellings and other properties, contamination of water supplies, the spreading of waterborne disease and disruption of orderly social and economic progress. Despite the building of barriers, dikes and levees to protect against flooding, major floods continue to cause extensive damage and prevent full utilisation of the land. Attempts to clear and maintain river channels, to assure the passage of water without obstruction, and to protect river banks and embankments with "river training works" have proven expensive and only marginally effective.
The future trend is likely to be one of increased flooding. Changes in the catchments beyond Bangladesh's northern and eastern borders — caused by deforestation and more intensive land use — are increasing the sediments carried by rivers and leading to bigger and bigger floods. Concurrently with the floods, the south-west monsoon winds raise the mean tide levels in the Bay of Bengal, reducing the slope and, hence, the rivers' discharge. Other factors which contribute to flooding are heavy rainfall, flat topography of the land, siltation of riverbeds and development of the flood plains.