River Bed Form Evolution Modelling for Flood Management Purposes

Type

PhD-research


Persons involved

S. Naqshband (PhD student)

O.J.M. van Duin (PhD student)

Prof. Dr Suzanne J.M.H. Hulscher (promoter)

dr. ir. C.M. Dohmen-Janssen

dr.ir. J.S. Ribberink

dr.ir. F.M. Sterlini-van der Meer

dr.ir A.J. Paarlberg (HKV)


Funding

STW / Braunschweig University of Technology / University of Twente / Rijkswaterstaat / Deltares


Duration

2010 – 2014


Summary:

During floods, bedforms develop on the river bed. Dunes are the most common bedforms in lowland river channels consisting of sand and gravel. They have heights of 10-30% of the water depth and lengths around 10 times their height. River bedforms influence water levels significantly, because they impose roughness on the flow. In general, increasing dimensions lead to increasing water levels. Knowledge about bedform evolution and associated roughness remains limited. The current project will generate knowledge about and improve a forecasting model that describes river bedform evolution developed by Paarlberg et al. [2006; 2007] will be improved. The prediction of evolution of river dunes will be improved and the transition to upper-stage plane beds will be implemented. Subsequently, the results will be translated into roughness predictors that will be implemented in the FEWS-NL flood early warning system. Therefore the project will lead to improved water level forecasts with reduced uncertainties and thus to more reliable flood warnings; the number of unexpected floods (a flood, but no warning) and the number of unnecessary flood warnings (a warning, but no flood) will be reduced.