Sedimentation and flow patterns induced by regular and modified groynes on the River Elbe, Germany

Abstract

ABSTRACTGroynes help to protect river banks and support water levels for navigation. Since recently, groyne fields are considered as surrogate habitat for various species and may, in terms of ecology, partially replace flood plains that were lost in the course of river training in the last centuries. In order to maintain and improve the hydraulic function and ecological value of groyne fields, the German Federal Institutes of Hydrology and the Waterways Engineering and Research studied innovative groyne types and regular groynes on the River Elbe, Germany. In a 10‐year field campaign, groyne field hydraulics and morphology were monitored using acoustic Doppler current profiler and echo‐sounding techniques. The data is used to assess groyne field heterogeneity and morphodynamics over the 10‐year period as well as flow patterns at different flow stages. The results indicate a high morphological activity in the groyne fields associated with flood discharges. Significant sedimentation in the bank regions was observed, whereas sedimentation in deeper areas of the groyne fields was less pronounced. The sedimentation patterns and rates in the groyne fields are, to some extent, found to be influenced by different groyne types and associated flow patterns. Copyright © 2013 John Wiley & Sons, Ltd.