Experts and authorities have cited the STPs not functioning up to the desired standards, untapped drains discharging effluents directly into the Yamuna, the lack of focus on alternative nature-based solutions, the construction and urbanisation on its banks that have led to an overall reduction of freshwater, and the tussle between the Lieutenant Governor (L-G) and the Delhi government among the major issues.
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Environmentalist Vimlendu Jha told ThePrint that a main challenge is also the lack of political intent and urgency. The river is not clean because the Yamuna is not the priority, he added.
“So Delhi has a world-class airport but has the world’s most pathetic air and world’s most pathetic river. Is it for us to, therefore, celebrate the airport or be ashamed of public health and public ecology?” Jha said. “So that is where the main challenge of Yamuna is lack of empathy, ignorance, will and urgency.”
With Delhi set to vote on 5 February, the issue has returned to the centre of political discourse.
Over the past few months, the Bharatiya Janata Party (BJP) campaigns have accused the Aam Aadmi Party (AAP) government of failing to clean the river. While former Delhi chief minister Arvind Kejriwal has accepted that it was a promise that he wasn’t able to fulfil, last week he also blamed the BJP-led Haryana government for “poisoning” Yamuna’s water.
However, this time, all parties featured the cleaning of the Yamuna in their manifestos. “So whoever wins, the fact that Yamuna is a part of the narrative, hopefully, Yamuna will not be ignored in the next five years because they can’t get away with it now,” Jha said.
Also Read: Watch CutTheClutter: The Yamuna pollution crisis in Delhi & politicisation of river clean-up efforts
‘Quiet flows maili Yamuna’
54 km of the Yamuna flows through the National Capital Territory (NCT) of Delhi, starting from Palla village in the north and exiting from Jaitpur in the southeast. It also forms the inter-state border between Delhi and Uttar Pradesh.
Of the 54 km, the river flows a distance of approximately 22 km through urban Delhi—from Wazirabad Barrage to Okhla Barrage.
Though only 2 percent of its total length of the 1,376 km, according to the National Green Tribunal (NGT)’s Yamuna Monitoring Committee report, the stretch accounts for over 75 percent of its total pollution load. A major cause of pollution is the 22 drains in Delhi dumping sewage and industrial effluents in the river.
Efforts to clean Yamuna began decades ago. In 1994, a newspaper report, titled ‘And Quiet Flows Maili (dirty) Yamuna’, caught the Supreme Court’s attention and it took it upon itself to ensure that the river was cleaned.
Over the years, the top court passed several landmark orders to that effect. For instance, in 2004, it created a committee to oversee the bridging of the gap in waste generation and treatment.
However, in 2012, with around Rs. 4,400 crore having been spent over 18 years in efforts to clean it, the apex court was questioning why the Yamuna was still polluted.
Around the same time, litigants were gearing up to take this issue to the newly formed NGT. In January 2015, the NGT devised a plan to convert “maili” Yamuna” into a “nirmal” (clean) Yamuna, with the ‘Maili se Nirmal Yamuna Revitalisation Plan’ for 2017.
In 2017, the Supreme Court also transferred the Public Interest Litigation (PIL) pending before it to the NGT on the ground that there could not be parallel proceedings on the same issue.
However, by 2018, the NGT also expressed its dissatisfaction over the repeated failure of various authorities in carrying out its directions. That year, it constituted a monitoring committee to oversee the implementation of its orders.
From overseeing the STP operation in Delhi, Haryana and Uttar Pradesh to addressing untreated effluents being discharged into the river, the NGT has passed several directions over the years. However, it is often met with non-compliance and the court expressed its discontent with the cleaning efforts.
STPs do not meet prescribed standards
The water quality status of the river Yamuna progressively worsens as it winds its way through the national capital.
A Delhi Pollution Control Committee in December 2024 said that, at Palla, the river had a Biochemical Oxygen Demand (BOD) of 4 mg/litre, against the desired level of 3 mg/l. But by the time the river reaches the last monitoring station at Asgarpur, after crossing the confluence of the Shahdara and Tughlakabad drains, its BOD stood at 70.
BOD indicates how much oxygen is required to break down organic matter in water, one of the methods to assess the health of water bodies.
Furthermore, its faecal coliform levels stood at 1,200 MPN (most probable number)/100 ml against the desired level of 500 MPN/100ml and maximum permissible level of 2,500 MPN/100ml.
At Asgarpur, the faecal levels, an indication of untreated sewage and high-level pollution, were also at an all-time high—a whopping 84,00,000 MPN (most probable number)/100 ml. This was 16,800 times the desired level and 3,360 times the maximum permissible level.
The STPs are supposed to take care of this untreated sewage. However, there is ample evidence in official records that shows STPs in Delhi are not providing the desired results.
Under parameters set by the Central Pollution Control Board (CPCB), STPs should have BOD and Total Suspended Solid (TSS) values below 10mg/l post-treatment. TSS are solid particles present in water that are large enough to be trapped by a filter. High levels of TSS indicate poor quality, which affects aquatic life.
However, old STPs were made on the parameters that required the BOD to be below 30 mg/l.
While the CPCB requires the faecal coliform rate to be 230 MPN/100 m/l or less, the levels were found to be much higher than this limit even post-treatment at at least 20 STPs in October 2024. The number reached over 10 times the prescribed limit—2,500 units—at Yamuna Pillar STP.
Similarly, the report said that the BOD and TSS levels were 2-3 times the permissible limits.
The DPCC’s October 2024 report also said that 20 of Delhi’s 37 STPs did not meet the standards prescribed by CPCB. “Letters are issued regularly to the Delhi Jal Board (DJB) for taking rectification measures to meet the prescribed standards.”
Additionally, October 2024 data shows that, on average, Delhi generates around 800 MGD of waste, roughly 360 crore liters per day. But the STPs currently have the capacity to only treat around 712 MGD of wastewater.
A DPCC report from May 2023 said that, by June 2024, the STPs in Delhi would be able to treat 964.5 MGD at the upgraded parameters of 10 BOD and 10 TSS (10:10). On paper, this would cover the treatment of all the waste generated in the Capital.
However, in an affidavit filed by the DJB before the NGT in October 2024, only 392 MGD was being treated with the upgraded parameters of 10:10. The rest of the plants, it said, would be upgraded to the parameters only by December 2025.
‘Work or face contempt’
In addition to the NGT and the Supreme Court, the Delhi High Court has also been monitoring the STP issue since April 2024.
Noting that STPs were releasing untreated sewage in the Yamuna river in November last year, the court said tamper-proof meters must be installed to record the operational timings and electricity consumption of STPs. This data must be loaded in real-time on the website of CPCB, DJB and the chief secretary’s office, it said.
It also said that all STPs must install sensors at the point of discharge—the point where the STP drains release the treated water into the Yamuna river—to record the quality and quantity of treated, water, including details of BOD, Chemical Oxygen Demand (COD), TSS, faecal coliform and dissolved phosphate.
However, during the latest hearing in the case on 28 January, DJB chief engineer Bhupesh Kumar told the court that, of the 37 STPs in Delhi, flow meters had been installed only at the effluent outlets of 22 STPs. Kumar said flow meters would be installed, after the tender process, in another 4 STPs by March 2025 and in the remaining 11 STPs by June 2025.
However, on more digging, the court found that in the 22 STPs that Kumar referred to, flow meters had been installed 4 to 5 years ago as a part of the construction project. This meant that no flow meters had been installed after the court’s directions in November 2024.
Calling this position “completely non-acceptable”, the bench observed, “This clearly gives an impression to the Court that the DJB has not taken the orders of this Court seriously and till date only estimates being prepared is the answer that Mr. Bhupesh Kumar has given to the Court.”
It even said that in case of further inaction, it would not hesitate in initiating contempt proceedings against the concerned officials.
A DJB official believes that fixing STPs is the key to cleaning the Yamuna. “All units, their electrical and mechanical parts should run properly and should be 100 percent functional, and there should be stringent monitoring of electrical and mechanical parts,” he told ThePrint. “I can guarantee that 70 to 80 percent of the pollution load on Yamuna will be reduced.”
He also suggested that there should be stringent monitoring of the electrical and mechanical equipment through IOT (Internet of Things).
Tapping the drains
This also links to the issue of the tapping—connecting to an STP—of drains. According to the DPCC monthly progress report for October 2024, 22 major drains fall into the river Yamuna in Delhi. Of these, only 9 drains had been fully tapped and 2 drains had been partially tapped.
In the case of the Najafgarh and Shahdara drains, two of the largest drains, the report said that it was “technically not feasible” to tap the entire drain. So, it said, the drains were brought under the ‘interceptor sewer project’ to tap sub-drains and divert them to STPs for treatment.
According to reports, the Najafgarh drain is responsible for nearly 70 percent of wastewater discharge into the Yamuna. Around 110 MGD of wastewater falling into Yamuna originates in Haryana—leading to Delhi often blaming its neighbour for the pollution in Yamuna.
Pankaj Kumar said correcting the quality of water in the drains was key to cleaning the Yamuna.
“Until we correct the water quality standards of the drains, we cannot clean the Yamuna. And the water quality standards of the drains won’t improve until their STPs work properly,” he told ThePrint. “The drains are the mediators, the water from the drains go into the Yamuna, and STPs water go into the drains.”
Other experts also suggest different treatment mechanisms to improve the water in the drains.
“I am fully convinced that we will have to enter the drains, keep them clean, and remediate the water by some nature based solutions,” a former government official associated with the Centre’s Namami Gange Programme or the National Mission for Clean (NMCG) told ThePrint, emphasising on in situ treatments mechanisms for the drains.
Professor C.R. Babu highlighted the importance of a drainage map—separating storm drains from the sewer system. “Identify primary, secondary and tertiary drains. Use in situ bioremediation, that would reduce the load of the STPs,” he said.
Babu chaired an expert committee formed by the Ministry of Environment and Forests in 2013. He was behind the biodiversity parks in Delhi, including the Yamuna Biodiversity Park.
Despite the fact that the schematic diagram shows the drains emptying their water into the river starting from Wazirabad, between Palla and Wazirabad, the fecal coliform levels doubled. The increase from from 1,200 MPN/100 ml at Palla to 3,300 MPN/100 ml at Wazirabad indicates that untracked effluents are being released in the Yamuna.
Additionally, a number of Delhi’s 1,799 unauthorised colonies still lack a sewer line.
“1,210 colonies have sewer lines, but others are under progress. But this waste from these sewer lines is also going to some drain and then into the river. So despite putting in so much money into laying of sewer lines, there isn’t an end-to-end connectivity linking these sewer lines to STPs,” the former NMCG official quoted above told ThePrint.
Politics over the funds
With so many parties and governments involved in the process, it is also not clear how much has been spent so far on the efforts to clean the river with some funds under contest.
The response to an Right to Information (RTI) query filed by Delhi-based environment activist Amit Gupta said that the DJB received over Rs 1,078 crore between 2015 and 2023 and Rs 205 crore between 2018 and 2023 under the NMCG mission for the Yamuna Action Plan III. A total of 11 projects, at a cost of Rs 2,009.12 crore, have been sanctioned by the Centre under the NMCG as of 31 January 2024.
The official documents, seen by ThePrint, show that the projects include the construction of a 124 MGD Waste Water Treatment Plant (WWTP) at Okhla, the upgradation of WWTPs at Kondli and Rithala, and the construction of a 70 MGD WWTP at Coronation Pillar in Delhi.
However, the former NMCG official pointed to a delay in completion of these projects. “Between the process of tendering and award, it took more than 2 to 3 years because of slow decision-making,” he told ThePrint.
For instance, the Okhla construction was supposed to be completed by December 2022 but missed several deadlines because of delays in payments to contractors, sources in DJB and the NMCG told ThePrint. It is under execution only now.
DJB funds have also been a part of the tussle between the Delhi government and the Union government.
The AAP government approached the Supreme Court early last year, seeking release of funds for the board. It alleged that a part of the funds had not been released, despite the assembly passing the budget with the amount for maintaining and improving water supply to Delhi residents.
Representing the Delhi government, senior advocate A.M. Singhvi had told the court that the funds would lapse if they weren’t released before 31 March 2024. However, in response, the bench told Singhvi that even if it hears this petition after 31 March, the funds could be released if the court order is in the Delhi government’s favour.
While the Supreme Court website shows that this petition is still pending, an order passed on 1 April 2024 said that the DJB received a total of Rs 4,578.15 crore for the financial year of 2023-2024. This included an amount of Rs 760 crore which was received on 31 March 2024—the last day of the financial year.
However, while the Delhi government claimed that an amount of Rs 1,927 crores was still pending, the L-G V.K. Saxena’s lawyer told the court that he had “nothing to do” with the non-release of the balance amount.
On the next date of hearing on 5 April, the Supreme Court directed the Delhi government’s finance department to verify the amounts pending to the DJB and settle the dues.
Politics over credit
In January 2023, the NGT appointed a high-level committee, headed by the L-G, to oversee the cleaning of the river.
This committee was meant to look at a plan to use treated water for agriculture, horticulture or industrial purposes, prevent the dumping of any waste in the river, the protection of flood plain zones, and desilting and dredging of drains and the river.
However, in May that year, the AAP government approached the Supreme Court, challenging the appointment of L-G as the chair of this committee. The AAP’s petition asserted that the NGT order sidelined the elected government.
This NGT-appointed panel also included the Delhi chief secretary, the secretaries of the irrigation, forest and environment, agriculture, and the finance department of the Delhi government, the DJB CEO, the Delhi Development Authority (DDA) vice-chairman, and representatives from the ministries of agriculture and Jal Shakti or environment, the NMCG director-general, and the CPCB chairman, among others.
In July last year, the Supreme Court stayed the NGT order only to the extent that it directed the L-G to be a member of the Committee and to chair it.
The court said that the rest of the committee shall continue to function. However, it started a political row.
In a series of posts on ‘X’, Saxena, in November 2023, said, “Year after year. One promise after another. Froth, sewer, effluents remain unchecked. The floodplains get turned into dump yards and open toilets. COD/BOD, Coliform, E Coli… all markers damn the river.”
“Things just began to change in terms of cleaner flood plains, enhanced sewage treatment, land for new STPs & resultant slight improvements in water quality, the Govt convolutedly gets Hon’ble SC to modify NGT’s order,” he wrote. “And.. the Yamuna flows festering..!!”
The floodplain ecosystem
In addition to the focus on STPs and drains, experts, such as Professor C.R. Babu, have also advocated for “nature-based solutions” to rejuvenate the river.
He also recommended creating biodiversity parks alongside all major rivers in India. “Biodiversity parks conserve the river ecosystems, and sustain their ecological integrity.”
Babu placed special emphasis on maintaining the river’s floodplain ecosystems. “Our architects have simply copied the concept of Riverfront development from the West, particularly Europe, to promote tourism. But our rivers are entirely different. In the West, the rainfall is uniform, but our rivers are monsoon rivers,” he explained.
By carrying out development on the river ecosystem, “not only are you increasing the risk of flood, but also not allowing the floodwater to be stored in the floodplain wetlands,” he said. “So we’re losing out on the quantity of freshwater that can be available to the city by destroying the floodplains.”
When these floodplains have forests, they also regulate the temperature of the water. This leads to the water of the river being cleaner.
Highlighting that, in parts of the urban stretch of the river in Delhi—which is the most polluted—the floodplain has almost been reduced to zero, he said, “Until and unless you restore these different ecosystems, you cannot rejuvenate rivers.”
He also recommended that the water treated at STPs be given secondary and tertiary treatment before being discharged in the Yamuna. “This water should pass through treatment wetlands, and it will further reduce the pollutants. Wetlands have plants and microbes…Coliform density would also be reduced,” he told ThePrint.
Jha called the government the “largest violator and encroacher” of the floodplains.
“Urbanisation has also meant encroachment of the floodplains in terms of the construction that is happening…There has been a lot of construction that has happened in Delhi on the floodplains and wetlands—be it Pragati Maidan, or Delhi Secretariat, or Commonwealth Games, or Okhla,” he explained.
“All of this takes away the recharge capacity of the river.”
The thick layers of foam that obscure the view of the water are a visual representation of the high levels of pollution in the Yamuna. But it has done little to raise sensitivity of the issue, according to Pankaj.
“The biggest problem is that we are not sensitive towards this…We are not considering waste management as skilled work, so we have to hire people who are skilled in managing solid and liquid waste,” he said.
Meanwhile, Jha advocated for a more scientific approach. The final solution “cannot be a band aid solution”.
(Edited by Sanya Mathur)
Also Read: 3 reasons Kejriwal gave to justify his allegation of Yamuna water being ‘poisoned’, EC not convinced
