Geospatial approach for assessment of vulnerability to flood in local self governments

S Deepak,Gopika Rajan,P G Jairaj

doi:10.1186/s40677-020-00172-w

Abstract

Recent years have shown a significant increase in the occurrence of floods globally, with an impact on habitation and different sectors of the economy. This, in turn, necessitates the use of different flood mitigation strategies, wherein flood vulnerability assessment plays a significant role. The proposed work presents a methodology that combines vulnerability under physical-environmental and socio-economic domains to assess the overall flood vulnerability at the local self-government level. The methodology was illustrated to the case of Aluva municipality, located on the banks of River Periyar, in Kerala state, India. The spatial variation of hazard inducing factors and population statistics were analysed using Geographic Information System (GIS) tools. The machine learning algorithm, Random Forest, which uses hazard inducing factors as input was implemented for the evaluation of physical-environmental vulnerability. The social vulnerability of the region was analysed using the GIS Multi-criteria decision analysis approach (MCDA), with criteria weights to incorporate the interests of different stakeholders. The critical combinations of the two domains of vulnerability in the assessment of the vulnerability to flood, to have efficient flood management in local self-government was demonstrated in this study and can be made use of for any flood event.

Highlights

In the present century, floods are one of the most devastating and costly hazards worldwide, its contribution can be attributed to factors like climate change impacts on the hydrologic cycle, land-use changes and increased density of habitation activities in flood-prone areas
In the socio-economic vulnerability assessment of the population in the municipality, an approximately equal percentage of low vulnerable area and high vulnerable area are seen in the study
Fifteen exhibited very high vulnerability with respect to these objectives, which must be probably due to the presence of thatched houses along with houses having dilapidated living conditions in the ward

Summary

Introduction

Floods are one of the most devastating and costly hazards worldwide, its contribution can be attributed to factors like climate change impacts on the hydrologic cycle, land-use changes and increased density of habitation activities in flood-prone areas. To mitigate the adverse impacts of flood, the design and implementation of risk management strategies are necessary. Flood vulnerability is used as a multi-dimensional measure of the potential damage the human settlement inhabiting in the local self-government may encounter during a flood event, which is a totality of socio-economic conditions of the people and physical-environmental condition of the area. The physical and environmental component represents the changes in milieu due to human or natural activities, topography, meteorological factors, and hydrologic parameters, which influence the vulnerability of the region to flood (Balica and Wright 2010)

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Results

Conclusion