Water is the vital natural resource essential for the survival of mankind. Rainfall is the main source of water which is unevenly distributed spatially and temporally. Unprecedented increase in population, urbanization, agricultural expansion and industrialization leads to higher levels of human activities. As water demand increases, issues on water availability and demand become critical. This makes the management of water resources, such as assessing, managing and planning of water resources for sustainable use, a complex task. Therefore, it is essential to make measurement of factors such as size, slope, soil type and land use, vegetation and flow capacity of the channel. The drainage area, length of the water courses and mainstream are the most significant variables for prediction of run–off. Geospatial Technology has been efficiently used in generating input parameters of hydrological models. In the present investigation, an attempt has been made to develop a GIS based Watershed Model for the assessment of spatial distribution of runoff for the Velchal Project in Mominpet mandal in Ranga Reddy, Telangana, India. The GIS layers namely, contours, stream network were prepared including watershed boundary. A Hydrological Model of the study area was also generated in ArcGIS using Contours and Stream layers. Subsequently Slope and Aspect maps were generated for the study area.