Effect of idol immersion on water quality of Yamuna River in Delhi and its potential influence on ground water quality

Present study consists of observing changes in physical (temperature and TDS) and chemical changes in water quality (pH, hardness and heavy metal content) due to immersion of idols before, during and after the idol immersion ceremonies in Yamuna River, Delhi during the year 2014. Special emphasis was given on Durga puja festival for which water collected from designated immersion points (Shyam Ghat, ITO, ISBT and Kalindi Kunj) was analyzed for hardness (magnesium, calcium) and heavy metals (lead, iron, cadmium, nickel, manganese, and chromate). There was significant change in physico-chemical parameters during the time of immersion at each of the immersion site of the Yamuna River. Subsequently, their content decreases due to release of additional fresh water upstream as a part of government's adaptive measures. Deterioration of ground water quality cannot be stopped and ground water continues to pollute with subsurface sediments. Surface water and groundwater quality are adversely affected by the existing idol immersion practices.