pollution level of Ganga in 2014
Answers
The dissolved oxygen level has improved at 27 locations while biochemical oxygen demand (BOD) and faecal coliform (FC) has improved at 42 and 21 locations, respectively, the information provided by the ministry to Kochi-based Right to Information applicant, K Govindan Nampoothiry, stated.
The ministry has provided an annual average of Ganga water quality on these three parameters, thereby discounting the season variations.
These parameters help in understanding the water quality of an aquatic system. Higher dissolved oxygen (national standard is 5 milligram per litre or more) shows whether water can sustain aquatic life. Lower BOD (national standard is 3 milligram per litre or less) shows there is less amount of bacteria and other microorganisms in water. Faecal coliform (national standard less is than 2,500 coliform in 100 ml of water) indicates the amount of sewage in water.
recent report by the Central Pollution Control Board (CPCB), which the government has put under wrap for several months, shows that the Ganga became more polluted along its stretch in Uttarakhand between 2014 and 2018, while in the remaining stretch in Uttar Pradesh, Bihar and West Bengal it remained as polluted in 2018 as it was in 2014.
The CPCB scientists classified the Ganga’s water quality into five categories — clean, slight, moderate, heavy and severe — in the increasing order of pollution. They conducted pollution monitoring at 36 locations along the stretch of the Ganga in two seasons — before and after monsoon — in 2017-18. They then compared the water quality at 23 of these locations for which data were also available for 2014-15.