Vol. 9, Issue 1, Part L (2025)

The present study was undertaken with the objective of monitoring historical changes in suspended sediments of Shivsagar Reservoir, Satara located in Maharashtra using Google Earth Engine (GEE) cloud computing. The study was conducted based on remotely sensed satellite data. Normalized Difference Suspended Sediment Index (NDSSI) values were computed using satellite imagery over the study area. Suspended sediment concentration over the area was also estimated using regression equation based on NDSSI. In the due process NDSSI and SSC were mapped in Shivsagar reservoir for the year 2000 and 2020 using Landsat 7 top of the atmosphere (TOA) and Landsat 8 TOA satellite imagery, respectively. Outcomes of study indicated that, mean monthly NDSSI values showed decreasing trend from January to May month and gradual increasing trend from June to December month over the study period. Mean NDSSI values for winter and Post Monsoon season were observed to be 0.4352 and 0.4187, respectively. Similarly, mean NDSSI values for Pre-Monsoon and Monsoon seasons were 0.2496 and 0.2474, respectively. It was therefore inferred that; turbid water having higher suspended sediment concentrations is present during pre-monsoon and monsoon seasons and clear water with lower suspended sediment concentration was present during winter and post monsoon season. Also, higher values of NDSSI values were seen in the year 2000 than year 2020. Estimated Suspended Sediment Concentration (SSC) values over most of the areas in Shivasagar Lake in the year 2000 were in the range of 86.83-773.52 mg/litre whereas, for year 2020 SSC values were in the range of 94.74- 2815.35 mg/litre. It is concluded that, GEE cloud computing can be effectively used for monitoring changes in the SSC of reservoirs.