The two main objectives of TRM are uniform rising of land
inside a beel and maintaining of proper drainage capacity of
river. But due to the lack of technical and social limitations in
TRM operation, sedimentation inside the beel was found to be
non-uniform. Therefore in this study three socially acceptable
sediment management options for the two tidal basins were
identified through discussions and consultations with the focus
group of the local stakeholders. And the technical feasibility
of these options was assessed by a cohesive sediment transport
model using MIKE 21 Flow Model FM modeling system.
Besides, economic analysis had also been carried out to select
the most suitable option. Comparing all the options through
technical, social and economic aspects, finally opting-2 is
clearly found to be the preferred option for the TRM
application. In this option, embankments were considered
along both banks of the main channels through the beel and
thereby allow sedimentation by gradually cutting the
embankment part by part from upstream to downstream.
The models were simulated for a period of four years in this
study. However further simulation for a longer period may be
carried out to determine the actual required life time of a tidal
basin. In addition, water level, discharge and sediment data at
several locations can be collected to get better performance of
the numerical model for future studies. Furthermore
sedimentation volume can be calculated from direct field
measurements and can be compared with the simulated result
which will also help to clarify the sediment distribution over
the entire basin area.