Volumetric Vairations of Inland Water Body: A Case STDY of Manchar Lake

Abstract

Lakes are one of the primary sources of fresh water, and theirsize variations provide information critical to their sustainable management in the backdrop of seasonal and climatic changes. Satellite-based optical images and radar altimetertogether have provided significant advances in monitoring inland water bodies like lakes and reservoirs, and asses its water storage capacity. Optical imageries are usually good for identifying the extent of lakes with a certain margin of error, whereas Satellite radar altimetry is helpful in monitoring temporal variations in water surface heights.This study focuses on the method used to monitor MancharLake’s surface area along with its volume. Time series altimetry data provided by European satellite Sentinel 3and optical data of Landsat 8 (30m spatial resolution) were used to calculate area, while temporal analysis wasperformed to generate lake boundaries usingNormalized Difference Water Index (NDWI). The lake volume was estimated by using water level variation from altimetry and surface area. Further, a relationship between Rating curves and volume was developed in order to calculate water flow at different outlets of Manchar Lake.