Wave attenuation by vegetation applied on dike design

Abstract

Wave attenuation by vegetation on the foreland can reduce hydraulic loads on dikes. Literature study showed the reliability issues within several methods. The currently most popular method is based largely on an empirical constant, called the bulk drag coefficient. Several datasets were analyzed to find a relation for this coefficient. With the use of this data a quantitative method and tool was developed for computations of this effect. The impact of the vegetation on the design crest height and dike cover was significant. However, current methods for the computation of this effect are still to unreliable for application in practice.