INTEGRATED WATERSHED MODELING AND CHARACTERIZATION USING FEM, GIS & REMOTE SENSING TECHNIQUES

Abstract

ABSTRACT The digital revolution in the last few decades made possible the modeling of watershed by integration of different hydrologic processes occurring on the watershed. The recent advances in watershed modeling are the integrated use of numerical methods, remote sensing and GIS technologies. Numerical methods are used in the solution of the governing equations for the rainfall runoff simulation. Remote sensing technology solved the problem of data needs of watershed modeling. GIS made its usefulness in the processing of large quantities of data, which is essential in watershed modeling. In the present paper, characterization of watershed for the key parameters such as drainage, slope, Land Use (LU)/Land Cover (LC) by using Geographical information systems (GIS) and remotely sensed data has been discussed. Runoff estimation by Finite Element Method (FEM) based model by using inputs derived from the watershed characteristic maps has been presented. GIS has been used to prepare the finite element grid map and input files such as Manning's roughness and slope used in the model for the watershed. LU/LC of the watershed has been derived from remotely sensed data. FEM has been used to solve the diffusion wave equations for one dimensional surface runoff model which is coupled with Philip infiltration model. Watershed characterization and runoff estimation has been done for few rainfall events in Banha watershed, India. The methodology can be used in various watershed development schemes.