There is a need to undertake the cleaning of individual watersheds of the river basin on a decentralised basis, providing local solutions to local problems/origins of pollution. Tapping pollution at the local level will not only help in curbing it at the source but will also make the system sustainable
With March 22 being celebrated as World Water Day each year, it is pertinent to take stock of India’s efforts to clean the most revered river of the country, the Ganga. Namami Gange the flagship programme which aims to clean Ganga on a mission mode, gets considerable attention from the Central Government in terms of funds and priority. Namami Gange lays much emphasis on pollution abatement through the improvement of sewage infrastructure. However, despite the concerted efforts being made towards cleaning the river, the results have not been very promising. The data from the Central Pollution Control Board (CPCB) indicate that there was no change in the water quality of the river between 2014-2018 in terms of bacteriological parameters. The CPCB has also been monitoring the organic load in the priority drains entering the river. In 2018, the pre-monsoon data showed that the drains discharged water of biochemical oxygen demand (BOD) varying from 2.48 tonnes per day (TPD) to as high as 241.17 TPD. Further, the CPCB has also installed real-time water quality monitoring of the Ganga near the ghats and the drains entering the river, which highlights the areas with BOD higher than three mg/L. Further, the data from CPCB indicates that most of the river water from the stretch between Uttar Pradesh to West Bengal is unfit for drinking and at some places for bathing as well.
Another major cause of concern is the non-point source of pollution. The Government’s effort, in this case, has only been restricted to provide toilets in the villages at the bank of the river but there has been no strategy for other non-point sources of pollution such as farm and cattle waste runoff. Regulatory authorities do not monitor these pollution sources and the focus is only on monitoring sewage-related contaminants.
There clearly exists a gap in the effective implementation of this mission mode programme. The main objective of this flagship programme was to stop direct dumping of waste into the river by having effluent treatment plants and sewage infrastructure in all major riverine cities. Under this objective, the target was to create sewage treatment capacity for 3,700 million litres per day (MLD). However, by February 2019, the Government could only create a capacity of 480 MLD.
Some of the reasons for ineffective implementation can be sourced from the report of the Comptroller and Auditor General in 2017, which highlighted unused funds, lack of staff and the absence of long-term planning. Because of this mismanagement a large amount of solid and liquid waste still finds its way into the river unchecked. The extended deadline of 2020 has promised that most of the drains would stop discharging filth into the river but this seems difficult to achieve unless the focus changes from centralised solutions to a decentralised ones.
One of the main interventions by the Government was setting up effluent/sewage treatment plants at a city level i.e. the centralised systems. This was because a greater population could be served and also to maximise the environmental and social gains. Such systems have been able to improve the quality of the river to some extent and also reduce further deterioration. But at many places, these treatment plants were designed according to the future needs and hence involved huge costs, while running under capacity. The Government’s plan to clean the river on mission mode might not lead to the desired results unless there is a shift towards the decentralised systems which is further strengthened through active stakeholders’ participation. These systems should be supported by the bye-laws of city management rules. It helps to treat the wastewater generated in small localities. The treated wastewater could be reused in replenishing the local water bodies. Further, such systems have several advantages such as lower costs, the potential to gradually increase the capacity, environmental benefits and also increased opportunities for reuse of the effluents.
Decentralised systems that can be undertaken for wastewater management include septic tanks, waste stabilisation ponds, constructed wetlands, membrane bioreactors (MBR) and land treatment. A constructed wetland in Pompia, Greece is one example where it was used for treating the wastewater generated by the local community. Due to the wetland, the treated effluent was equivalent in terms of quality to the tertiary treated municipal wastewater. There were high removal rates for Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Total Kjeldahl Nitrogen (TKN), phosphorus, Total Coliform (TC) and Fecal Coliform (FC). Hence, it has a potential to be reused in several areas, especially irrigation. Given that the world is facing the exacerbating effects of climate change, the availability of treated water for non-potable purposes can reduce its deleterious impact on dwindling water resources. Decentralised systems in such scenarios can be dependable and cost-effective solutions and the treated effluent can either be reused in some application or for replenishing the drains/channels which feed into the rivers.
India has also been able to build the technologies of constructed (floating) wetlands such as the Phytorid Wastewater Treatment, which has been designed especially to treat industrial, municipal and agricultural wastewater. Siddheshwar Lake in Pachpakhadi, Dawala Lake in Ovala as well as Dativali Lake in Diva are a few examples in Thane, where this decentralised system has been used and was successful in reducing BOD and COD in the wastewater.
Such systems can be replicated at most of the places, especially the 100 riverine cities at the bank of the river Ganga. These systems can help India in solving two major problems of the sector — wastewater pollution and a declining availability of the resource by treating the wastewater and putting it to use for irrigation, landscaping and so on, which will reduce the burden on freshwater resources. It is also a way of adapting to the mounting stress of climate change.
The emphasis should be on breaking down the puzzle of river cleaning into smaller problems and the provision of sewerage infrastructure cannot be a one-size-fits-all solution. Each smaller problem should have a customised solution addressing it locally. Local bodies play a crucial role in this and they should be empowered to participate in the process of decision-making, implementation and facilitation to reuse treated wastewater.
There is a need to undertake the cleaning of individual watersheds of the basin on a decentralised basis, providing local solutions to local problems/origins of pollution. Tapping pollution at the local level will not only help in curbing it at the source but will also make the system sustainable.
(Grover is Fellow and Seth is Research Associate, Water Resources, TERI)