Surface Runoff Estimation using RS and GIS - A Case Study of Swarnamukhi River, India

For proper utilization and management of water, as in planning and design of water storage structures, channel improvement, estimation of surface runoff is essential. Geographic Information System (GIS) is specifically designed to merge maps with database and is well suited to work with all stages of hydrological modeling. Present study aims to quantify the hydrological response of the watershed, Konakaluva, a sub watershed of Sawarnamukhi River flowing across Rangampet, Srikalahasthi and drains into Bay of Bengal for different rainfall conditions. Remote sensing and GIS are used to overcome the inconveniences faced while using conventional methods for estimating runoff. In this project, Natural Resources Conservation System - Curve Number model is used for rainfall-runoff estimation using slope, vegetation cover and drainage density of the basin. Runoff depths are computed for average rainfall values. For an average infiltration condition, estimated surface runoff is 24.6 mm with correlation coefficient between the observed and predicted (modelled) runoffs being 0.78. This indicates the method is reliable in predicting the surface runoff of the catchment.