Assessment of Vulnerability to Urban Floods in Greater Mumbai, India Using Geospatial Techniques

Abstract

Abstract Urban flooding as well as its socio-economic repercussions is dramatically escalating globally in several coastal cities due to changes in rainfall patterns triggered by climate change. The principal aim of the study is to evaluate the flood vulnerable locations in Mumbai by using a multi-criteria evaluation (MCE) approach. The weights of flood-vulnerable impacting parameters like rainfall, slope, land use/cover (LULC), vicinity to sewers and storm water drainage, vicinity to natural drainage, vegetation, and soil are evaluated using the Analytical Hierarchy Process (AHP). The weights for said parameters are determined by using AHP, and they are as follows: rainfall (29.42%), slope (20.96%), LULC (17.52%), vicinity to sewers and storm water drainage (13.99%), vicinity to natural drainage (8.97%), vegetation (5.58%), and soil (3.56%). In the study area, it is estimated that 46.72% of the area is classified as being severe vulnerable, 18.74% of the area as high to very high and just 34.54% of the area as slight to moderate. Researchers were able to validate the modelling conclusion by examination of all 234 water-logged locations in the study area. Most of the water-logged spots i.e. 85.46% were found in areas that fall under the category of severe to very high vulnerability and only 14% of locations fall in other three categories as per the data of the flooding sites that are collected from MCGM authorities. These model-based flood vulnerable scenario maps are crucial for planning flood conservation and control measures to prioritize the area based on the degree of vulnerability.