A Comparative Assessment of Water Quality of the Koyna and Ujjani Reservoirs of Maharashtra, India: A Geospatial Approach

The present study evaluates the water quality of the Koyna and Ujjani reservoirs using Remote Sensing (RS) approach. For socio-economic development and as a part of the environmental indicator; water quality has a significant role in understanding the dynamics. This analysis is helpful to assess the water quality by RS-based index Normalized Difference Chlorophyll Index (NDCI), and Normalized Difference Turbidity Index (NDTI) for Koyna and Ujjani reservoirs. The study was conducted using secondary data from the Water Body Information System (WBIS) portal provided by the National Remote Sensing Centre. The analysis spanned a temporal duration of one year, specifically from 13 February 2022 to 10 March 2023. The water quality indicator such as NDCI, and NDTI having average values for the given period is studied from the environmental pollution perspective. Based on the available data, the average value for NDCI and NDTI for the Koyna reservoir was found to be −0.15 and −0.17, respectively. The average value for NDCI and NDTI for the Ujjani reservoir was found to be −0.10 and −0.17, respectively. The result has the potential to showcase the impact of anthropogenic activities on the water bodies and changes in the NDCI and NDVI at different temporal scales. The Earth Observation technology and its significance in analysis of water bodies and the demographic effects can be easily identified from this study.