Author(s): S. Van Vuren; L. E. Van Breen

Linked Author(s):

Keywords: Probabilistic modelling; Uncertainty analysis; Monte Carlo simulation; River management; River morphology; Floodplain lowering

Abstract: In the Netherlands a new flood protection policy, called Room for the Rivers, is implemented. Measures, other than dike strengthening, are considered in order to increase the flood conveyance capacity in the rivers. Examples of such measures are floodplain lowering and summer levee removal. This paper investigates to what extent these measures may lead to more bed level variability. Monte Carlo Simulation (MCS), applied to a 1D model of the River Rhine, is utilised to quantify the uncertainty in the morphological response given an uncertain river discharge. MCS involves a large number of model runs with statistically equivalent inputs. For each run a discharge hydrograph of hundred years duration has been synthesised on the basis of a probability distribution function. The morphological response statistics show that a large variation in bed level uncertainty exists: in space (due to irregularities in the river geometry) and in time (due to seasonal variation in discharge). Lowering floodplains and maintaining summer levees result in similar response as in the unchanged situation. Additional removal of the summer levees result in an increase of the bed level variability. The paper shows the need for research into uncertainties associated with modelling of river morphology.

DOI:

Year: 2003