Runoff Process Using By Overland Time of Concentration Model and

The integration strategy for a watershed can be carried out by various procedures. However a first step is usually a resource survey or inventory. This attempts to answer the question of the supply and demand for resources both natural and human resources. Depending upon the area involved, a survey may include socio characteristics, soil characteristics, land capacity/suitability classifications, hydrological assessment including climate characteristics, water use and other parameters as needed. Runoff is one of the important integral part of the integrated watershed management, so for this estimation of r catchment is a complex and complicated phenomenon governed by large number of known and unknown physiographic factors that vary both in space and time. Application of mathematical modeling techniques to t constituent processes involved in the physical processes of runoff generation has led to better understanding of the processes and their interaction. Conventional hydrological models for the prediction of runoff particularly over a basin require considerable hydrological and meteorological data. Collection of these data is expensive, time consuming and difficult process. ESRI software’s Arc view, Arc Info and Arc GIS 9.1 versions are helpful to compute the watershed parameters like slope map, drainage ma Remote Sensing technology and Geographical Information Systems (GIS) can augment the conventional methods to a great extent in rainfall runoff studies. In the present study a small agricultural watershed rainfall chosen. The advantage of formulating this model for the watershed is that it enables to generate the runoff. Once the model is formulated, calibrated and validated, the same can be applied to any watershed to estimate the runoff, even if the sub catchment is ungauged. Keeping these points in view, the rainfall Concentration Model has been formulated and developed. It contains three modules namely Time of Concentration, Rainfall and Soil Moisture module for the Rangareddy District, Andhra Pradesh, India has been considered for the study. It is concluded that the developed OTC model is a fairly good model and it is comparable with the standard mod viz., SCS-CN and TR-55 Model