Impact-Based Forecasting for Pluvial Floods

authored by

V. Rözer, A. Peche, S. Berkhahn, Y. Feng, L. Fuchs, T. Graf, U. Haberlandt, H. Kreibich, R. Sämann, M. Sester, B. Shehu, J. Wahl, I. Neuweiler

Abstract

Pluvial floods in urban areas are caused by local, fast storm events with very high rainfall rates, which lead to inundation of streets and buildings before the storm water reaches a watercourse. An increase in frequency and intensity of heavy rainfall events and an ongoing urbanization may further increase the risk of pluvial flooding in many urban areas. Currently, warnings for pluvial floods are mostly limited to information on rainfall intensities and durations over larger areas, which is often not detailed enough to effectively protect people and goods. We present a proof-of-concept for an impact-based forecasting system for pluvial floods. Using a model chain consisting of a rainfall forecast, an inundation, a contaminant transport and a damage model, we are able to provide predictions for the expected rainfall, the inundated areas, spreading of potential contamination and the expected damage to residential buildings. We use a neural network-based inundation model, which significantly reduces the computation time of the model chain. To demonstrate the feasibility, we perform a hindcast of a recent pluvial flood event in an urban area in Germany. The required spatio-temporal accuracy of rainfall forecasts is still a major challenge, but our results show that reliable impact-based warnings can be forecasts are available up to 5 min before the peak of an extreme rainfall event. Based on our results, we discuss how the outputs of the impact-based forecast could be used to disseminate impact-based early warnings.

Organisation(s)

Institute of Fluid Mechanics and Environmental Physics in Civil Engineering
Institute of Cartography and Geoinformatics
Institute of Hydrology and Water Resources Management
Leibniz Research Centre FZ:GEO

External Organisation(s)

London School of Economics and Political Science
Helmholtz Centre Potsdam - German Research Centre for Geosciences (GFZ)
Institute for Technical and Scientific Hydrology (itwh) GmbH

Type

Article

Journal

Earth's future

Volume

9

ISSN

2328-4277

Publication date

23.02.2021

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

General Environmental Science, Earth and Planetary Sciences (miscellaneous)

Sustainable Development Goals

SDG 11 - Sustainable Cities and Communities

Electronic version(s)

https://doi.org/10.1029/2020EF001851 (Access: Open)