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Sewage Treatment Plants in Delhi in Alarming Condition

Sewage Treatment Plants (STPs) in Delhi face a pressing crisis. Entrusted with the crucial task of purifying wastewater, these plants have fallen into a dire state, sparking alarming concerns.

By The Probe team
New Update

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. 

"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. 

Sewage Treatment Plants in Alarming Condition

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