A Grid-based Approach for Spatial Vulnerability Assessment to Floods: a Case Study on the Coastal Area of Bangladesh

Vulnerability assessment is a significant component of effective disaster management. Following the Hyogo Framework for Action 2005-2015, countries need to identify appropriate vulnerability indicators and to assess the impact of disasters. Vulnerability assessment is a prerequisite for disaster risk reduction and capacity building of communities. It can play an important role especially for developing countries to achieve the Millennium Development Goals (MDGs). At present, no standard method of vulnerability assessment exists. Different scientific communities follow different approaches. In this paper, the authors present a grid-based approach for spatial vulnerability assessment to floods with special reference to Bangladesh. Some advantages of a raster (or ‘grid’)based approach are demonstrated particularly to overcome the problems of data availability and to increase the transferability and applicability of a spatial vulnerability assessment. At first, a GIS-based approach is developed to transform census-based population data to 100x100 m population grids. Different vulnerability domains and indicators are selected in consultation with disaster experts, stakeholders, and the community people. As vulnerability is multidimensional, a comprehensive approach is followed, which reflects various physical, social, economic and environmental factors. Relative weights are assigned to the selected vulnerability domains and indicators on the basis of expert opinions using the Analytic Hierarchy Process (AHP) and pairwise comparisons. Then spatial vulnerabilities are assessed using the GIS weighted overlay techniques. Finally, the authors present some key findings and discuss the transferability of the approach to other areas. * Corresponding author.