Chapter 11 - GIS Application in floods mapping in the Ganges–Padma River basins in Bangladesh

Abstract

The physical characteristics of geographic location, river’s morphology, and the monsoon climate render Bangladesh highly vulnerable to natural disasters, primarily, floods, and cyclones. The GBM river carries 2.4 billion tons of sediments annually, and these sediments are settled on the bed of the major rivers channel and remaining portion carried into the Bay of Bengal. The newly emerged land in the river channel is called char or diara. Purba Khas Bandarkhola mouza is a unique char, and a revenue village is located in the Padma River basin. The excess water during the monsoon causes widespread flooding that damages char-land settlements, agricultural crops, infrastructures, communication networks, and livelihood. The dwellers are displaced from the char and again come back to the native char when the new land emerges in the river channel. The objective of this study is to develop a comprehensive plan for char-land sustainable settlement, people sustainability, and livelihood in the Padma River channel. The cyclic dislodgment range is 90km2, and pull and push factors are the root cause of displacement. Therefore, an integrated management plan is necessary for the char-land livelihood, migration, and settlement sustainability.