Characterizing the 2014 Indus River flooding using hydraulic simulations and satellite images

Rivers play an essential role to humans and ecosystems, but they also burst their banks during floods, often causing extensive damage to crops, property, and loss of lives. This paper characterizes the 2014 flood of the Indus River in Pakistan using the US Army Corps of Engineers Hydrologic Engineering Centre River Analysis System (HEC-RAS) model, integrated into a Geographic Information System (GIS), and satellite images from Landsat-8. The model is used to estimate the spatial extent of the flood and assess the damage that it caused by examining changes to the different Land Use/Land Cover (LULC) types of the river basin. Extreme flows for different return periods were esti-mated using a flood frequency analysis using a log-Pearson III distribution, which the Kolmogorov-Smirnov (KS) test identified as the best distribution to characterize the flow regime of the Indus river at Taunsa Barrage. The output of the flood frequency analysis was then incorporated into the HEC-RAS model to determine the spatial extent of the 2014 flood, with the accuracy of this modelling approach assessed using images from the Moderate Resolution Imaging Spectroradiometer (MODIS). The results reveal good agreement between simulated and obtained flood from the MODIS images, with an overall classification accuracy of more than 85%. The results also revealed that the most affected LULC in the watershed was crop/agricultural land, of which 50% was affected by the flood. This paper provides further evidence of the benefit of using a hydrological model and satellite images for flood monitoring and for flood damage assessment to inform the development of risk mitigation strategies