Analyzing the Impact of Temporal Landcover Changes on the Runoff Component of a Catchment Using Geospatial Techniques

Abstract

Globally, the issue of urbanization has been a matter of concern over the past few decades. Unplanned urban growth alters the natural drainage pattern and the water cycle, consequently, giving rise to floods. The floods are attributed to heavy precipitation but, human activities act as a catalyst in creating an imbalance in the environmental harmony. Predominantly, urban floods in the developing nations are known to affect quite a large population and infrastructure. Nagpur, in Maharashtra, India has been facing hydro-meteorological events in the last decade along with a persistent reduction of natural land and rapid urban growth. The paper attempts to establish a relationship between temporal landcover change for years 1995, 2005, 2015 and increased surface runoff eventually causing urban floods through application of the Soil Conservation Services Curve Number method. These years marked a remarkable urban development in Nagpur hence were considered. The outcome demonstrated a prominent urban sprawl of 12.84 percent and a severe loss of 16.32 percent in natural vegetation between 1995 and 2015. This paper examines the relationship between urban expansion and runoff at the catchment level by integrating land use/cover mapping with the hydrological model. Although the potential impact is expected, this study can further confirm it and facilitate policymakers developing policies to mitigate flooding-caused damages.