Flood Modelling at Downstream of Punjnad Headworks Using Historical Data

Abstract

The research project is aimed at developing flood models for Punjnad Headworks downstream areas up to Guddu Barrage with special emphasis on the economically vulnerable areas. The project will develop a discharge-versus-extent relation for flood modeling using historical discharge data, digital elevation models (DEMs) and Geographic Information Systems (GIS). The suggested approach firstly extracts the flood inundation areas using the NDWI (Normalized Difference Water Index) from four Landsat 8 imageries. Then, applying different flood modelling techniques i.e HEC-RAS flood simulation, Flood inundation using Elevation-discharge relationship and the final approach used was Distance-discharge relation. In which the relation between the distance of the marked extents perpendicular to the river centerline of river and the known discharges were developed and regression analysis was carried out. Lastly, the flood extent is generated based on Distance-discharge relationships. We expect that the suggested methodology will help underdeveloped and developing countries to obtain flood maps, which have difficulties getting flood maps through traditional approaches based on computer modeling.