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Dire State of Delhi's Sewage Treatment Plants Raises Alarming Concerns

In Delhi, a pressing crisis looms beneath the surface. The national capital’s Sewage Treatment Plants (STPs), entrusted with the crucial task of purifying wastewater, have fallen into a dire state, sparking alarming concerns. A majority of the STPs in Delhi have failed to conform to prescribed standards, posing serious concerns for public health and the environment.

By The Probe team
New Update


Produced below are the abridged version of the transcripts of the video story on the dire state of Delhi's Sewage Treatment Plants (STPs)

The sewage treatment plants in Delhi have long been under scrutiny for their poor water treatment capabilities. However, the situation now is so critical that the poor conditions of these plants are directly impacting both public health and the environment.

According to the data gathered by the Delhi Pollution Control Committee (DPCC), out of the 35 operational Sewage Treatment Plants (STPs) in Delhi, 22 have not conformed to the prescribed standards. "These sewage treatment plants, which DPCC has said are not meeting the NGT mandated standards, were old assets. They were constructed and designed for certain design parameters and honourable NGT in its order of 30th April 2019 mandated stringent parameters to the STPs, and these STPs weren't designed for those. So, therefore these STPs remain non-compliant with respect to the stringent design parameters and a few of them, because of technological issues, are non-compliant. So, these STPs need to be retrofitted. These need to be upgraded in terms of technology," explains D.P. Mathuria, Executive Director (Technical) of the National Mission for Clean Ganga.

During our visits to several STPs across Delhi, such as the Coronation Pillar STP, Kondli Phase IV STP, Mehrauli STP, Molarband STP, Okhla Phase 2, Phase 3, Phase 4 STPs, and the Yamuna Vihar Phase 1, Phase 2, Phase 3 STPs, we found that most of them had not conformed to the prescribed standards. The poor technological capabilities of the STPs themselves may be one of the major challenges, but this problem runs even deeper. 

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"One of the biggest resettlement colonies in Savda Ghevra doesn't have a sewage system. So, it is based on septic tanks built under the property. A large population of Delhi, therefore, their sewage is entering the river," states Depinder Kapur, Programme Director of the Centre for Science and Environment.

Another major issue compounding the existing crisis is the fact that several drains in Delhi are discharging untreated water into the Yamuna River. "Treated water, even from the STPs, is released into Yamuna or released into nullahs. 50 per cent of Delhi's sewage is flowing in the nullahs and other neighbouring states' sewage is also coming in. Whatever you are treating, 40-50 per cent, you are putting it back in the same nullah, it doesn't help," says Kapur.

Delhi generates 792 MGD of sewage daily and has 35 Sewage Treatment Plants at 20 locations. However, these 35 STPs can only treat a combined total of 632 MGD of sewage, which means that Delhi already has a gap of 160 MGD in its sewage treatment capacity. "One of our important findings in the Centre for Science and Environment's lab report tests which we have done for STPs is that somehow there are 1 or 2 parameters which most of our STPs cannot handle," notes Kapur.

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While the Delhi Jal Board has taken steps to improve the capacity and technology of STPs, timely execution is crucial as any more delays could have severe consequences for public health and the environment. "There are about 20 odd numbers of STPs which require upgradation both in terms of technology and capacity. Delhi Jal Board took up these initiatives, and they have identified agencies for retrofitting and upgrading, and they are doing this work against some timelines. The deadline is around mid of next year," states Mathuria.

The critical state of Delhi's sewage treatment plants, the discharge of untreated water into rivers and poor urban planning all continue to pose a severe threat to public health. While urgent action is the need of the hour, the consequences of inaction are far-reaching and irreversible.

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