Impact of urbanization on effective impervious area of Ahmedabad city in India

Abstract

ABSTRACT With increasing urbanization and population pressure, the barren ground is altered from undisturbed soils to disturbed soils, which multiplies fast growth of impervious areas in cities. An impervious area is a modified surface that prevents water from infiltrating into the soil. Hydraulically connected impervious areas are denoted as effective impervious area (EIA) and hydraulically disconnected are denoted as non-effective impervious area (NEIA). The summation of above two impervious covers amounts to the total impervious area (TIA). Impervious surface data is important for urban planning and environmental and resources management. Therefore, remote sensing of impervious surfaces in the urban areas has recently attracted unprecedented attention. The estimation of TIA is comparatively simple as compared to the estimation of EIA, despite the fact that later is viewed as more proper for hydrologic studies. In this paper, emphasis was given on the estimation of impervious area (TIA) for the year 2000 and 2014 to scrutinize urbanization growth of Ahmedabad city in India using medium resolution satellite imageries by using geospatial techniques under the ArcGIS 10.1 platform. The more hydraulically relevant EIA is estimated using two indirect methods, i.e. empirical equations derived from the whole basin or sub-basin parameters from the estimated TIA and using an annual hydrograph methodology. A graphical demonstration of the estimated EIA and TIA for different years is illustrated to analyze the rate of urban expansion.