A pre-feasibility study of navigation channel regulation works in North Channel, Yangtze estuary

In this study, the feasibility of navigation channel regulation works in North Channelis explored in order to achieve the design water depth in North Channel.A phased Improvement Project of Deep-draft Channel in North Passage has beencarried out from 1998 to 2009. Until 2005, the second phase project achieved a 10meter deep-draft navigation channel in North Passage. A 12.5 meter deep channel willbe achieved in 2009.With the rapid development of water borne cargo transport associated with theincreasing of the density of large-scale vessels in the North Passage, it is necessary tohave another deep navigation channel in Yangtze Estuary. The North Channel will bean ideal potential navigation channel for distributing the increasing vessels.The objectives of the study are to increase the understanding of complexhydrodynamics conditions and morphological processes in Yangtze Estuary especiallyin North Channel, to simulate the complex patterns of cohesive sedimentstransportation, deposition and re-suspension due to river runoff and tide, salt mixing,etc. The optimal configuration of the North Channel is the ultimate goal.Firstly, a Delft-3D hydrodynamic flow model with domain decomposition technologyis set up and used to simulate the current and tide behaviour of different alternatives.The model is calibrated and validated using the measured data.Secondly, 2D and 3D morphological model are applied. Salt intrusion, sedimenttransportation, sedimentation and erosion and morphological processes are simulated.The suspended sediment concentration distribution and the morphological changes arealso calibrated with measured data. The morphological evolution of North Channelafter the implementation of regulation works is studied and it shows reasonabletendency.The relationship between the tidal prism and the river cross-section are alsodemonstrated. The results are consisted with previous study.The study obtains an optimal configuration of the regulation works in the NorthChannel. Further requirements of the study are also recommended