Estimation of sediment in vaigai reservoir using remote sensing technique and swat modelling

Abstract

The overall growth of any nation depends upon the development of natural resources and it is the need of the hour to preserve the resources for future generation. In this context, the role of water resources plays an important element in the development of a country. Nowadays, most of the reservoirs formed on natural water courses are losing their capacity due to sedimentation, which causes many ecological and environmental problems. Many of world s hydro electric power and irrigation reservoirs have been receiving continuous threats due to heavy sedimentation. Estimation of sediment yield in the reservoir can facilitate the determination of probable life span of the reservoir and take appropriate mitigation measures to limit reservoir sedimentation. In this perspective, this research is carried out to estimate the sediment in Vaigai reservoir, Tamil Nadu, India and also to adopt newlineproper conservation measures to reduce the sedimentation .Estimation of sediment in Vaigai reservoir has been carried out by making use of Remote Sensing Technique with satellite imageries of different over pass dates. For this purpose, ASTER satellite imageries of nine different over pass dates (from year 2000 to 2014) were collected. The water spread area of the reservoir on the satellite over pass dates was calculated using Geographical Information System (GIS) and the corresponding water levels or elevations were obtained from the authorities concerned. SWAT Model was used to predict the sedimentation in Vaigai reservoir. Land use, soil, slope, weather and discharge data were given as input parameters for simulation and discharge and sediment yield for various years were obtained as output. Change in land use classes in the catchment area for different years were analysed and the impact of land use changes on sedimentation in the reservoir was studied. Physico chemical characteristics of the soil in the reservoir was found and the presence of nutrients were analysed. Moreover, the suitability of the soil in the catchment area for various uses was also explored. newline newline