Data collection and analysis
For all three regions of different flow regimes, time series of river
discharge, water level, and suspended sediment concentration (SSC) at
representative locations were collected (Figure 1). Available data were
collected from governmental agencies such as Bangladesh Water
Development Board (BWDB), Water Resources Planning Organization (WARPO)
and non-governmental research institutes such as Institute of Water
Modelling (IWM), Center for Environmental and Geographic Information
Services (CEGIS), as well as reports and papers. Hourly water level data
were available for all representative locations., but continuous
measurements of discharge and SSC were available only for short periods
of time, or at irregular time intervals. The average monthly discharge
of the Gorai River at the bifurcation from the Ganges River and average
monthly rainfall are presented in Figure 3. The annual hydrographs for
the different flow regimes at the selected locations are shown in Figure
2. From these data, mean tidal range and average SSC during three
seasons for three flow regimes were calculated.