During the rainy months of the year the river is in full spate and people still enjoy many pursuits but such activities can be dangerous as the pollution in the river once the flow reduces contains harmful pathogens as well as high levels of heavy metals caused chiefly by idol immersion and industrial effluent.

Control of river coliform is essential as the Yamuna is used by thousands of people for fishing and bathing. Coliforms are disease-causing pathogens/bacteria present in sewage. Coliform pollution refers to pathogens and bacteria which are dangerous being potential sources of water borne diseases like hepatitis-A, cholera, typhoid, ring/hook worm etc. 

As against the CPCB standard of 5000 MPN/100 ml for class C River, coliforms in Yamuna in Delhi are at an astronomically high level of 31.8 million. Such pollutants are more harmful than organic (BOD) called Biological Oxygen Demand. Awareness about coliform is very poor.

Courtesy: Sreedeep Bhattacharya