Pollution levels down by 30 per cent
Rising in the Himalayas and emptying into the Bay of Bengal, the Ganges has been subjected to heavy pollution over recent decades.
However, following the Covid-19 lockdown there are signs the holy river is being rejuvenated with increased signs of biodiversity.
Professor BD Tripathi, chairman of the Mahamana Malaviya Research Centre for Ganga, River Development and Water Resource Management recently tested the biochemical oxygen demand (BOD) and dissolved oxygen (DO) level in the Ganga.
He said water pollution has decreased by as much as 25-30 per cent during the lockdown.
He told the Hindustan Times: “We found that the concentration of dissolved oxygen increased by 20 per cent to 30 per cent in Ganga water and the concentration of biochemical oxygen decreased from 35 per cent to 40 per cent.”
As well as the Ganges, there are signs of cleaner and clearer skies and wildlife flourishing in the Venice canals following lockdowns across the world.
Sustaining the improvements
Himanshu Thakkar coordinator at South Asia Network on Dams, Rivers & People (SANDRP) said the state of Ganga has significantly improved in the lockdown period at most locations along the main stem and several tributaries.
He told Aquatech Online: “A number of factors are responsible, the major ones being stopping industrial effluents, a huge reduction in socio-cultural load and some increased flow due to above average pre-monsoon rains.”
This included the higher contribution of snowmelt following significantly high snowfall in winter in the Himalayan catchments.
Thakkar reported that at some locations there is “clear improvement in riverine biodiversity” and even CPCB (Central Pollution Control Board) and state PCBs (Pollution Control Boards) are certifying the improvement.
“To sustain this improvement, the government needs to ensure that no untreated or even semi treated industrial effluents enter the river.”
“To sustain this improvement, the government needs to change the functioning of SPCBs (State Pollution Control Boards) and CPCB to ensure that no untreated or even semi treated industrial effluents enter the river,” he added.
“The changes needed are in terms of improving transparency, participatory management and accountability of these bodies as also of the urban municipal bodies. In addition, a lot of work is required to reduce the demand for water so that there are greater freshwater flows in the rivers."
External agencies such as foundation Ark2030 has earmarked south-east Asia – and the Ganges in particular – as one of five critical global landscapes that need rescuing.
In an interview with Aquatech Online, Stephen Fern, chairman of Ark2030, asked: “Has anyone looked at the Ganges from its multiple points to when it enters the ocean and what can be done to clean it up?”
He said: “There has never been a single strategic programme. We believe that if we can learn lessons from the Ganges - which is one of the 10 top rivers accounting for 95 per cent of the pollutants in the oceans - we can solve the problem at the root. By stopping the plastic from getting into the ocean in the first place, it means we can then stop trawling around the oceans collecting waste.”
Fern explained that the Foundation intends to invest in a one-year programme that involves “identifying strategically” the core elements of the materials that end up in the Ganga’s water at the mouth of the estuary.
“Once those things are identified, you look holistically at what can be done; whether it’s legislation or government action on enforcement with legislation. Look at how the Thames has been cleaned up in the UK. You need water authorities and legislation to bring water to life again.”