Capturing Flood Risk Perception via Sketch Maps

Abstract

The fact that an increasing number of people and local authorities are affected by natural hazards, especially floods, highlights the necessity of adequate mitigation and preparedness within disaster management. Many governments, though, have only insufficient monetary or technological capacities. One possible approach to tackle these issues is the acquisition of information by sketch maps complemented by questionnaires, which allows to digitally capture flood risk perception. We investigate which factors influence information collected by sketch maps and questionnaires in case studies in an area prone to pluvial flooding in Santiago de Chile. Our aim is to gain more information about the methods applied. Hereby, we focus on the spatial acquisition scale of sketch maps and personal characteristics of the participants, for example, whether they live at this very location of the survey (residents) or are pedestrians passing by. Our results show that the choice of the acquisition scale of the base map influences the amount and level of detail of information captured via sketch maps. Thus, detail base maps lead to more precise results when compared to reference data, especially in the case of residents. The results also reveal that the place of living of the respondents has an effect on the resulting information because on the neighborhood level the risk perception of residents is more detailed than the one of pedestrians. The study suggests that the integration of citizens via sketch maps can provide information about flood risk perception, and thus can influence the flood mitigation in the area.

Benford’s law and geographical information – the example of OpenStreetMap

“…As there exist many alternative ways of assessing data quality, as is suggested by data quality ontologies (Wand and Wang 1996, Frank 2007, Goodchild and Li 2012, Mocnik et al 2018, it seems logical to explore the additional benefits of using Benford's law in combination with other approaches. For instance, parts of the data that turn out not to follow Benford's law might be compared to local knowledge (Poiani et al 2016, Klonner et al 2018. Future research might discuss how such different methods can be tightly integrated to improve the quality of the actual assessment as well as corresponding actions to improve the data.…”

Studying the Spatial Distribution of Volunteered Geographic Data Through a Non-parametric Approach

“…Given that the spatial data collected through the map-based approach are a subjective truth, the context in which they are gathered matter. For example, Klonner et al [ 11 ] in their work on flood risk perceptions well exemplify this issue by underling that while a participant may be motivated to identify a certain site because his/her property has been heavily affected, another neighbor might not have the same incentive, despite the original problem being the same. Similarly, in our research, the information reported is based on everyday living experience and so the participant’s context should be accounted.…”

An Open Data Approach to Mapping Urban Drainage Infrastructure in Developing Communities

“…Crowdsourcing mapping methods are especially effective under conditions where there is limited historical data, such as urban flooding, and community perceptions can be used as a means to fill gaps in traditional datasets. For example, Klonner et al [29,30] applied this concept in combining quantitative OSM and qualitative community spatial data in Santiago, Chile. The generated maps highlighted sensitive areas of interest for flood management.…”