Exploring the potential of multivariate depth‐damage and rainfall‐damage models

Abstract

In Europe, floods are among the natural catastrophes that cause the largest economic damage. This article explores the potential of two distinct types of multivariate flood damage models: ‘depth‐damage’ models and ‘rainfall‐damage’ models. We use survey data of 346 Flemish households that were victim of pluvial floods complemented with rainfall data from both rain gauges and weather radars. In the econometrical analysis, a Tobit estimation technique is used to deal with the issue of zero damage observations. The results show that in the ‘depth‐damage’ models flood depth has a significant impact on the damage. In the ‘rainfall‐damage’ models there is a significant impact of rainfall accumulation on the damage when using the gauge rainfall data as predictor, but not when using the radar rainfall data. Finally, non‐hazard indicators are found to be important for explaining pluvial flood damage in both ‘depth‐damage’ and ‘rainfall‐damage’ models.

Weather radar rainfall data in urban hydrology

“…Ntegeka et al (2015) have shown how probabilistic urban inundation risk maps can be obtained by combining STEPSbased rainfall nowcasts with a nested 1-D-2-D sewer hydraulic and surface inundation model, and a model to assess the damages and social consequences of the urban inundations (Van Ootegem et al, 2017). Such a system, however, only becomes useful for operational management when the uncertainties in the inundation risks can be communicated in a compact and clear way, and when these are informative and manageable by decision makers or the wider public.…”

The impact of intense rainfall on insurance losses in two Swedish cities

“…Our results are a contribution in the field of "rainfalldamage" approaches as discussed by Van Ootegem et al (2018). In future, the estimation of flood damage from rainfall intensity could be a first step in the assessment of pluvial flood risk in regions, where hydraulic models are not available or suitable.…”

“…After checking a number of intense rainfall events in Sundsvall in 2001, Orust in 2002, Hagfors in 2004 and Gothenburg in 2011 reported in the Swedish Natural Hazard Information System (MSB, ), and with respect to the findings of Van Ootegem et al () and Grahn and Nyberg () addressing radar data in flood damage studies, we made the decision to use rain gauge data instead of radar data in this study. Comparisons between gauge data and radar data showed remarkable differences in rainfall amounts, in one particular case as much as 100 mm (Sundsvall August 27, 2001, 133 mm/24 hr rain gauge, 33 mm/24 hr radar).…”

“…Van Ootegem et al () studied the potential of “depth‐damage models” versus “rainfall‐damage models” in the context of pluvial flooding. The authors found that the rainfall amount from rain gauges has a significant impact on the monetary damage, and explained between 9 and 19% of the variance of the damages.…”

“…They found rainfall as an important driver for flood damage and the relation between rainfall intensity and flood damage as being non-linear. Van Ootegem et al (2018) studied the potential of "depth-damage models" versus "rainfall-damage models" in the context of pluvial flooding. The authors found that the rainfall amount from rain gauges has a significant impact on the monetary damage, and explained between 9 and 19% of the variance of the damages.…”