Characterization of the 2014 Indus River Flood Using Hydraulic Simulations and Satellite Images

Aqil Tariq,Nguyen Thi Thuy Linh,Saima Siddiqui,Alban Kuriqi,Quoc Bao Pham,Linlin Lu,Alexandre S Gagnon,Hong Shu

doi:10.3390/rs13112053

Abstract

Rivers play an essential role to humans and ecosystems, but they also burst their banks during floods, often causing extensive damage to crop, 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 estimated 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 show that a supervised classification of the Landsat images was able to identify the LULC types of the study region with a high degree of accuracy, and that the most affected LULC was crop/agricultural land, of which 50% was affected by the 2014 flood. Finally, the hydraulic simulation of extent of the 2014 flood was found to visually compare very well with the MODIS image, and the surface area of floods of different return periods was calculated. This paper provides further evidence of the benefit of using a hydrological model and satellite images for flood mapping and for flood damage assessment to inform the development of risk mitigation strategies.

Highlights

Flooding is one of the most common environmental hazards, affecting many countries worldwide [1]
This study proposed a modelling approach using geographic information system (GIS) and remote sensing (RS) to depict the spatial extent of the 2014 flood of the Indus River in Pakistan, comparing the model output with
Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery, and determining the extent of floods of different return periods for the basin, in addition to assessing the damage caused by the flood

Summary

Introduction

Flooding is one of the most common environmental hazards, affecting many countries worldwide [1]. The Indus River is the longest river [2] and the most crucial water source in Pakistan, providing water to irrigate the land that produces 90% of the agricultural outputs of the country [3]. To better cope with the two extremes of the hydrological cycle, barrages and dams were built along the Indus River to store water during dry periods and to protect against the risk of flooding, respectively [5,6]. One such barrage is Taunsa Barrage, whose flood attenuation capability has decreased over the years due to severe sedimentation [7]

Methods

Results

Discussion

Conclusion