Assessment of Surface Runoff for a Watershed using GIS and SCS Curve Number Techniques

Abstract

Water is essential to life and plays a vital role for the survival of the human being on earth. Surface by flow over the land surface and it is the major source runoff refers to the loss of water from an area for all surface water bodies such as the tanks and Reservoirs. It occurs when rain falls with intensity greater than the infiltration capacity of the soil. The accurate estimation of depth and rate of runoff are the key parameters for watershed management. In the present study, Soil conservation curve number method was used to determine run off depth and runoff volume on different rainfall conditions with the aid of GIS technology. The land cover pattern and soil type map provides spatial information on land cover, soils as input to SCS model. The study area Kamatchipuram watershed is located in the Northwestern part of the Kodaganar river basin, Dindigul district. Geographical information system arises as an efficient tool for the preparation of most of the input data required by the SCS curve number model and it is the most suitable for analysis of the runoff distribution of any watershed area.