Sten Esbjørn Kristensen

LONG TERM MODELING OF SHORELINE RESPONSE TO COASTAL STRUCTURES

A new model concept for shoreline evolution is applied to the case of an offshore breakwater. The model is verified against bathymetrical surveys performed 4 years after the breakwater construction, and used to predict the consequences of an alternative design. The model concept is based on the combination of a one-line type of schematization of the nearshore morphology with a 2DH area modeling approach for waves, currents and sediment transport. This concept makes a model capable of taking into account: 1) variation in the offshore bathymetry and 2) the effect of coastal structures on waves and currents, and hence on sediment transport and shoreline response. The model results show very good quantitative and qualitative agreement with the observed morphology in the case of the original breakwater layout, and the results from the alternative breakwater layout demonstrate the model’s potential as a tool for shoreline assessment studies.