Application of Geo-Spatial Technique for Flood Inundation Mapping of Low Lying Areas

Abstract

Flooding is one of the severe disaster causes mass demolition of properties and affected human lives. In hazardous flood of year 2006, 90–95 % of Surat city, India, was under water and so that local planner as well as decision makers need accurate information on the spatial distribution, magnitude, depth of flooding and land use affected by such floods. Surat city is majorly partitioned into seven different zones named north zone, east zone, central zone, south zone, southeast zone, south-west zone, and west zone. Purpose of this study is to determine inundation of water in low laying areas of west zone. By procedure of Georeference along with Ground Control Point (GCP) and GPS points, 0.5 m interval contour map for west zone is introduced. Digitization of contour through GIS software and Digital Elevation Model (DEM) of West Zone through ArcGIS software is carried out. Probable submergence area for rescue work is also scrutinized. Graph of submergence area of West Zone according Town Planning Scheme (TPS) versus water level and flood Inundation map are generated which specify that West Zone and its TPS are low lying areas in Surat whose 20–25 km2 area will be submerge when water level exceeds 12 m height (MSL). The accuracy and validation of DEM is calculated by comparison with actual observed data at the time of flooding.