61-Continuous Simulation Model for Hydrologic Forecasting Based on Modified SCS-CN Concept.

Abstract

A new lumped conceptual model based on the modified Soil Conservation Service Curve Number (SCS-CN) concept has been proposed in this paper for long-term hydrologic simulation and it has been tested using the data of three catchments from different climatic and geographic settings of India. The proposed model based on modified SCS-CN concept has been compared with a lumped conceptual model based on Variable Source Area (VSA) theory (Mishra et at., 2005). The comparison revealed the proposed model to perform better in all applications. Both the models however exhibited a better match between the simulated and observed runoff in high runoff producing watersheds than did in low runoff producing catchments. The performance was evaluated in terms of the catchment response and the streamflow generation by producing satisfactory results through model efficiency and relative error. Using the results of the proposed model, dominant/dormant processes involved in watershed's runoff generating mechanism were also identified.