Conference Papers
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506
Browse
2 results
Search Results
Item Water level retrieval and water body mapping: A case study of nagarjuna sagar reservoir(Springer Science and Business Media Deutschland GmbH, 2021) Nalluri, N.; Ramesh, H.Satellite radar altimetry is exclusively designed for the oceanographic studies such as wind speed, sea surface level, tide height, and volumetric changes. In spite of the fact that the satellite radar altimetry is predominantly intended for oceanographic studies and ice sheet monitoring these days, the utilization of altimetry information is reached out to think about water dimension of inland water bodies like reservoirs, rivers and so on. This study covers the use of SENTINEL-3 Ku/C Radar Altimeter (SRAL) for the monitoring water level of Nagarjuna Sagar reservoir located in Telangana state, India. Satellite altimetry works on the principle of range measurement that is the measure of the travel time of microwave pulse from emission to receiving which is interrupted by many atmospheric conditions which cause a disturbance in travel time of microwave pulse which is to be adjusted to get corrected depth of water level. The SRAL information is handled utilizing Broadview Radar Altimetry Toolbox (BRAT) programming. The consistency of derived water level is compared using field data, and all the depths are within error range of one meter. Water body mapping is carried out utilizing cloud-free data of Landsat-8 from January 2016 to March 2019 which showed a gradual decrease in water level from November to May. © Springer Nature Singapore Pte Ltd 2021.Item Water Level Monitoring and Mapping Seasonal Changes in the Reservoir Body Using Altimetry Data: A Case Study of Shivsagar/Koyna Reservoir(Springer Science and Business Media Deutschland GmbH, 2025) Nalluri, A.; Ramesh, H.Water is essential to human existence, and current research emphasizes the need to monitor freshwater bodies. A considerable segment of India is presently struggling with a condition of water stress. Monitoring of rivers, reservoirs and lakes is always a booming question in a field of research where it comes to a question of minimal cost and time. Gauging stations are disappearing because of the high maintenance cost of Indian Reservoirs. The use of satellite data can help to aid in minimizing all these parameters with effective results. Monitoring of smaller reservoirs is highly unlikely to occur. Satellite altimetry has been successful in monitoring inland water bodies for the past three decades. The current study emphasizes using SARAL/Altika, one of India’s high-frequency satellites in the field of altimetry, to monitor water levels (WL) of Koyna Reservoir, which is located over the Koyna River in the state of Maharashtra, India. The seasonal water spread of the reservoir is mapped with the use of Landsat-8 imaging satellite, 30 m resolution, which has a particular band to monitor water. BRAT (Broad view radar altimetry toolbox) is used for processing SARAL. Bias correction is observed while calculating water level from altimetry which is mainly caused due to geography of the reservoir. The normalized differential water index (NDWI) is employed to derive the water spread area of the reservoir. A capacity survey of the reservoir is quantified, and a loss of reservoir storage over the years is calculated using a mathematical approach. SARAL/Altika and Landsat-8 data’s which are freely available and downloaded and processed from April 2013 to May 2016. SARAL/Altika derived WL has validated against the field WL. The coefficient of determination, R2 is 0.9 for all the years, and the root-mean-square error (RMSE) is found to be less than 0.3. Additionally, altimetry studies can be employed for deriving bathymetry information, monitoring river systems, reservoir operations and various other applications. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.