Influence of geomorphic and anthropogenic activities on channel morphology of River Jhelum in Kashmir Valley, NW Himalayas

Abstract

The Srinagar reach of the River Jhelum in Kashmir Valley, India exhibits complex meandering and variable width (47–180m) and depth (0.76–6.09m). The reach is characterised by sharp bends in the river course, channel sinuosity, linearity of meander bends, linear truncation of braid-bars, and concavities and convexities in the river channel reflecting varied river geomorphic processes. During the extreme hydrological event of September 2014, a large number of river breaches occurred along the river Jhelum, particularly in the Srinagar stretch of the river, due to the floodwaters overflowing the banks and the consequent bank erosion. The flooding situation was aggravated over the years by anthropogenic influences like the extensive urbanization of the Jhelum floodplains, encroachment of river banks and siltation of water courses due to the deforestation in the catchment and the shrinkage of wetlands which usually act as sponge during the flooding events. To establish a relationship between the geomorphic processes and anthropogenic activities on river morphology, we used various geomorphic parameters and techniques like river profiling, bathymetric profiling, lateral entrenchment ratio, water velocity, sinuosity index, supported by GPS and other field measurements. The impact of the geomorphic and human induced changes on the channel morphology was corroborated with the data from the river breaches that occurred during the 2014 flooding, a few of which occurred at the locations where geological structures (lineaments/faults) cut across the river banks. Based on the investigations from this study, it is suggested that varied geomorphic processes and the unchecked anthropogenic activities in the vicinity and catchment have significantly impacted the channel morphology of the river Jhelum in Kashmir Valley increasing the vulnerability of the Srinagar city to flooding.