Skip to main content
Infrastructure Resilience Conference 2018

Full Program »

A Surrogate Model for Worst Case Flood Impact Analysis in Complex River Systems

In comparison to local scale flood risk analysis, modelling flood losses and risks at river basin scale is challenging. Especially in mountainous watersheds, extreme precipitation can be distributed spatially and temporally with remarkable variability. Depending on the topography of the river basin and the topological characteristics of the river network, some rainfall patterns can lead to the synchronization of the flood peaks between tributaries and the main river. Thus, these complex interactions can lead to a high variability in the flood impacts. In addition, flood inundation modelling at river basin scale is computationally resource-intensive and the simulation of multiple scenarios is not always feasible. Here, we present a novel approach for reducing complexity in flood impact and flood loss modelling by decomposing the river system into a number of subsystems. A relationship between peak discharge and flood impacts is computed for every floodplain (subsystem) in the river basin by means of a flood inundation and flood impact model. The behavior of the system at river basin scale results from the behavior of the subsystems and is described by a surrogate model. This surrogate model allows to compute a high number of flood scenarios and their impacts to infrastructure for the whole river system without losing the accuracy of local scale flood modelling. It can be coupled with a hydrologic model. This offers new possibilities for stress test analyses and Monte-Carlo simulations to analyze the system behavior under different system loads (spatiotemporal patterns of rainfall). The method helps to identify the most sensitive and critical features of infrastructure in a river basin and thus it supports fostering resilience of infrastructure in case of extreme floods.

Andreas Paul Zischg
University of Bern
Switzerland

Veronika Röthlisberger
University of Bern
Switzerland

Guido Felder
University of Bern
Switzerland

Rolf Weingartner
University of Bern
Switzerland

 

Powered by OpenConf®
Copyright ©2002-2016 Zakon Group LLC