In Maharashtra, Ganesh Chaturthi is one of the major festivals celebrated, and many idols are immersed throughout the festival. Traditionally, idols were made of biodegradable materials like clay, but in recent times, various other harmful materials like POP (Plaster of Paris), oils and paints are used which tend to bioaccumulate in organisms. The present study analysed various physicochemical parameters of water which included temperature, turbidity, total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), conductivity, density, salinity, dissolved oxygen (DO), pH, hardness, nitrates, and phosphates, conducted before and after idol immersion at three sites in Mumbai: Juhu Beach, Marve Beach, and Dingeshwar Lake. The research observed changes in these parameters before and after the immersion of the idols which signified an increase in the level of pollution which may negatively affect the aquatic organisms’ health and lifestyle. The number of idols immersed in water bodies has increased over the years, and hence there is an urgent need to control water pollution. By adopting more sustainable measures for idol immersion, we can minimize the detrimental impacts on aquatic ecosystems.