Impact of groyne fields on the littoral drift: A hybrid morphological modelling study

The model results indicate a strong dependency of the reduction in littoral drift on the initial geometric bypass ratio (Qgeo*), which is defined from the groyne length and the littoral transport on the undisturbed coastline; Qgeo* is the transport occurring outside the tip of the groynes divided by the total transport. It is found that the sensitivity of the littoral drift to variations in groyne spacing and the angle, of the approaching waves, is inversely proportional to Qgeo*.