Determination of Effective Impervious Area for an Urban Indian Catchment

Abstract

AbstractDetermination of imperviousness, which is defined by total impervious area (TIA) and effective impervious area (EIA), is mandatory for hydrological modeling of water quantity and quality in urban areas. The determination of TIA is relatively easy and preferred to determination of EIA, even though the latter is considered to be more appropriate for hydrological studies. Accurate and representative determination of EIA requires knowledge of drainage network connectivity with the impervious surface, which cannot be ascertained from remote sensing data alone. A more realistic semiautomated direct method is suggested in this study to determine EIA by integrating the remote sensing data, the digital format of the drainage network, and a digital elevation model (DEM) of the study area. Based on the results obtained from the proposed method, a power relationship [EIA=0.0035×(TIA)2.17] relating easily measurable TIA and hydraulically relevant EIA was determined for an ungauged urban catchment in northeast ...