Tidal River Management TRM of Selected Coastal Area of Bangladesh For Mitigation of Drainage Congestion

The drainage congestion and sedimentation has been major issues over the years in Kobadak river basin Bangladesh. Kobadak River has been experiencing huge siltation over a long reach that reduces the drainage capacity of river and causing prolonged drainage congestion. It affects every sphere of life including cultivable lands employments culture fish production grazing land bio-diversity and live-stocks. Human interventions such as construction of polders bridges and encroachment into the river for cultivation deteriorated the condition of Kobadak River. The decrease of flushing flow from upstream and substantial reduction of tidal flooding area along the river by constructing polders caused severe siltation over a long stretch of the river. Sedimentation mainly occurs during dry season since tidal flow is restricted over the flood plain by constructing polders and there is no fresh water flow into Kobadak River from the Ganges River to flush the sediment during low tide. This study focuses on prevailing problems and solutions of long standing drainage congestion by applying TRM in Kobadak River basin area under Satkhira district in Jalalpur beel area.In this study to solve the drainage congestion problem for a long period of time by TRM process two options are suggested each with two different scenarios. Each option is assessed with cross dam without cross dam scenarios using MIKE-11 hydrodynamic modeling system.