PREDICTION OF FORMATION OF DYNAMICALLY STABLE EBB TIDAL DELTA AND MEASURES FOR PREVENTING OFFSHORE SAND LOSS

Takaaki Uda, Masumi Serizawa, Toshiro San-nami, Toshinori Ishikawa

Abstract


We developed a model for predicting the evolution of an ebb tidal delta based on the BG model, which was proposed by the present authors using the Bagnold concept of the equilibrium slope. Bathymetric changes around the inlet of Imagire-guchi between 1978 and 2005 were quantitatively analyzed to investigate the evolution of the ebb tidal delta and sand deposition offshore of the inlet. The model was applied to this inlet. The predicted bathymetric changes were in good agreement with the measured changes. Some measures for preventing the offshore sand loss were also considered by applying the model. The most effective measure was predicted to be cross-shore sand bypassing.

Keywords


ebb tidal delta; predictive model; beach changes; BG model; cross-shore sand bypassing

References


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