Chongqing downtown river reach lies in the fluctuating backwater district of Three Gorges Reservoir(TGR).After running on the 175M scheme of the TGR,it shows that the deposits increase accumulatively with the TGR running in the downtown reach,the bed sand will be finer,the river bar will be widen and higher,there will be bed evolution and the backwater area upwards.The sediment aggregation brings out important influence on harbor,navigation,the infrastructures and eco-environment along both banks of the reach.Combined with various respects of research achievements,the main engineering measurements are put forward in order to decrease the influence,such as soil conservation and building reservoirs upstream to prevent sand sedimentation,narrowing the flow to wash sand,bank regulation,harbor reconstruction and navigable channel treatment,etc.These measures have very good effect on decreasing deposition and eliminating the negative effects.