Water quality in the lower stretches of the River Ganga is in an alarming state, says the team of scientists from the Integrative Taxonomy and Microbial Ecology Research Group (ITMERG), IISER Kolkata, who have developed the baseline of water quality index (WQI) of the place. The team has reported a continuous deterioration of water quality, between 14-52, irrespective of the season of sampling. The scientists have also identified the point source along with type of pollutants, in particular forms of nitrogen with effect on biota along the 50 km stretch that required immediate intervention for effective river basin management.
The ITMERG team led by Professor Punyasloke Bhadury monitored nine sites encompassing 59 stations along 50 kms stretch of the lower stretches of the River Ganga over two years to understand the dynamics of key environmental variables, including forms of dissolved nitrogen along with biological proxies. Rapid human pressure and anthropogenic activities have led to untreated municipal and industrial sewages along with other pollutants in the lower stretches, especially close to the megapolis Kolkata, due to intense population pressure on both sides of the riverbanks. The state is disturbing with consequences for many unique and biodiversity ecosystems such as Sundarbans mangrove and endangered species like Gangetic dolphin.
Department of Science and Technology (DST)-Water Technology Initiative has supported the group to undertake this key study which has been published in the journal Environment Research Communications recently.
Box plots showing seasonal variation of key environmental parameters in the lower stretch of the River Ganga that are also known to influence WQI