A Semi – Distributed Water Balance Model for Amaravathi River Basin using Remote Sensing and GIS
Author(s)– Jenifa Latha.C, Saravanan.S, Palanichamy.K
Sustainable water management in a river basin requires knowledge of the water availability and water requirements of the basin in the present and future for various purposes. The complexity of the water system in the region can be understood by calculating the regional water balance in a distributed scale considering the factors that affect it. Water balance is defined as the net change in water, taking into account all the inflows to and outflows from a hydrologic system. Spatial variation due to distributed land-use, soil texture, topography, groundwater level, and hydrometeorological conditions should be accounted for in the water balance estimation. However, conventional spatially and temporally lumped estimates of water balance do not help much in the planning and development of water resources in the water shed. This is an important and current issue in the socially and economically valuable Amaravathi River Basin of Tamil Nadu. In this study, a spatially semi-distributed water balance model was developed to simulate mean monthly hydrological processes using landuse, soil texture, topography, and hydrometeorological data as input parameters in the Amaravathi River Basin, a semiarid region of Tamil Nadu in India. It is a physically based methodology for estimation of the average spatial distribution of water balance components. This model can be applicable in a public domain which can facilitate decision making. The water balance model is developed using SCS – CN (Soil Conservation Service – Curve Number) model to derive the runoff component and FAO-PM (Food and Agriculture Organization – Penman Monteith) model to derive the evapotranspiration component spatially with the help of remote sensing and GIS techniques.