Estimation of Distribution of Suspended Sediment...
The three-dimensional Shallow Water Equation Model（SWEM3D）was used to estimate the sediment concentration around the storage pools or pumping stations.
The governing equation is，
In which，S is salinity，C is sediment concentration，K V is vertical diffusion parameter.And，ρ＝ρ0＋0.78S＋0.62C.
The calculating mesh was shown as below.
Fig.4 mesh of sediment transportation numerical model
Given the tidal range was 4.2 m，the initial sediment concentration is 5 kg／m3 in the storage pool area，and suppose that all the sediment is suspended sediment and the bed load is neglected in this calculation.
The distributions of suspended sediment concentration during spring tide and ebb tide in the North Passage of Yangtze Estuary were shown as below.
Fig.5 distribution of SSC during spring tide
From the figures above，dumping dredged soil can cause the suspended sediment concentration surge significantly in the North Passage.This will increase the sediment supplying source and then increase the siltation in the navigation channel，considering that the loss ratio of dumped sediment is 72%.
Fig.6 distribution of SSC during ebb tide