Ganga's water quality improved since 2014
New Delhi: Ganga's water quality has significantly improved since 2014 with the entire length of the river having more dissolved oxygen than the prescribed minimum level, and 68 out of 97 monitoring locations compliant with bathing standards in terms of biochemical oxygen demand, a senior official said.
In an interview to PTI, National Mission for Clean Ganga Director General Rajiv Ranjan Mishra said 32 out of 53 locations monitoring biochemical oxygen demand (BOD) were compliant with the primary water quality criteria for bathing in 2014, whereas in 2021 the total monitoring stations increased to 97, out of which 68 monitoring locations were found compliant with BOD criteria for bathing.
BOD represents the amount of oxygen consumed by bacteria and other microorganisms. The greater the BOD, the more rapidly oxygen is depleted in the stream, which means less oxygen is available to higher forms of aquatic life. Mishra said the dissolved oxygen level of the Ganga has also improved.
"At present, the entire length of Ganga has more dissolved oxygen (DO) than the prescribed minimum level of 5 mg/l. The river water quality has shown improvement between 2014 and 2021," he said. The water quality of Ganga is assessed as per primary water quality standard for outdoor bathing in terms of dissolved oxygen (=5mg/L), BOD (=3mg/L) and faecal coliform (FC) (=2500 MPN/100ml) and (pH) (6.5-8.5).
Mishra said the steps taken to improve the water quality include abatement and control of source pollution by establishment or upgradation of wastewater treatment plants for the towns located on Ganga main stem and its tributaries, construction of crematoria, surface cleaning activities, solid waste management on the riverbanks and floodplains and refraining trash from drains falling into river Ganga by installation of trash racks at the mouth of drains.
"The outcome of these projects has started showing significant results and the water quality of river Ganga will further improve as more and more projects are operationalised," he said. Mishra said in Uttarakhand up to Haridwar, the river is meeting class A criteria, which is the highest level i.e., it meets DO, BOD and FC criteria.
"The NMCG's efforts towards cleaning of the river have been targeted towards meeting bathing quality criteria for river water. Out of the 351 polluted river stretches identified by the Central Pollution Control Board (CPCB) in India, no stretch of river Ganga falls in the top three priority categories," he said.
