Morphological modelling with suspended sediment transport in river bends

Depth-averaged morphological computations using Delft3D tend to produce ‘strange’, results for river bends when the sediment transport formulas of Van Rijn are used. Even pools in inner bend regions and bars in outer bend regions can result from the model. The objective of the present thesis is to identify the cause of the problem and propose...

Reshaping of beach nourishments under high angle of wave incidence

The morphological impact on nourishments of conditions with high oblique wave incidence has been investigated in literature using either a one-line approach or quasy-2D models. These models predict downdrift nourishment migration and the generation of alongshore sand waves for persistent conditions with high oblique wave incidence. However,...

Modelling far-field dredge plume dispersion

By its very nature dredging is an environmental impact, since dredging includes the excavation and/or relocation of sediment in a river, sea or estuary. One of the environmental impacts related to dredging is increased suspended sediment concentration (SSC) levels, forming plumes of sediment. These so called dredge plumes originate from spillage...

Morphodynamics of Ameland Inlet: Medium-term Delft3D Modelling

The Dutch Wadden Sea is consisting of 7 tidal inlet systems separated by sandy barrier islands. The general morphodynamics and hydrodynamics of tidal inlets are relatively well understood, but the detailed interactions remain a prominent research interest. In this study, process-based computer models are employed as a tool to investigate the...

Modelling sediment sorting near the large scale nourishment 'The Sand Motor': Understanding cause and impact of sediment sorting processes

The sediment composition of the sea bed is of relevance for various coastal properties such as bed forms, beach slopes and marine ecology. Furthermore it may significantly influence the morphological evolution of the coast. Knowledge about the processes forcing the spatial distribution of a certain grain size is therefore of great importance....

Evolution of beach extensions: Numerical modelling of large scale nourishments using UNIBEST & Delft3D

Recently, nourishments have been carried out on a large scale to counteract the on-going erosion along the Dutch Coast. The main advantage of these large beach extensions is that large stretches of coastline are protected for a long time scale (e.g. 20 years), which decreases the frequency of nourishing significantly. This is not only cost...

Fine Sediment Infill Reduction in Offshore Dredged Approach Channel

An offshore terminal is proposed to be constructed adjacent to the entrance of an Estuary in the Niger Delta. A dredged approach channel of around 10 km long, 250 m wide and to a depth of -14 m LAT is required to allow ships to reach the terminal. From earlier research it is found that high transport rates of fine sediment, in the order of 10...

Climate change and the morphological stability of the Tu Hien inlet, Vietnam

Historically, the coastal zone has always attracted people and across the globe the benefits of inlet systems have made communities settle there. The Tu Hien inlet and the Tam Giang–Cau Hai lagoon system in Vietnam are no exception, as approximately half a million people depend on it for their livelihood. Tidal inlets are also known for their...

Short Term Morphological Impact of the Eierlandsedam

After decades of coastal erosion in the north-west area of the Island of Texel, the shore-normal `Eierlandse Dam` had been built in 1995. The dam, situated in the outer delta of the Eierlandse Gat tidal inlet, resulted in a remarkable short-term morphological development of the adjacent coast. Four years following completion of the dam, large...