Delhi’s ambitious plan to improve water quality in the Yamuna River has gained significant momentum with the Delhi Jal Board (DJB) commencing work on 12 new sewage treatment plants (STPs) aimed at reducing the untreated sewage being discharged from the Najafgarh Drain.
This move comes as part of the ongoing efforts to clean the Yamuna and revitalise the river’s health, which has long been a major environmental concern for the national capital. With pollution levels in the Yamuna at alarming rates, experts and officials alike view this project as a crucial step in addressing the long-standing issue. The Najafgarh Drain, which contributes a large portion of untreated sewage flowing into the Yamuna, has been a major source of pollution in the river. The DJB has initiated the construction of a 49.5 million litres per day (MLD) wastewater treatment plant in Chhawla, southwest Delhi, as a key part of this project. In addition, the plans also include the development of smaller de-centralised sewage treatment plants (DSTPs) that will be strategically located across the areas that contribute significantly to the sewage flow.
The implementation of these treatment plants is in line with the Delhi government’s broader strategy to clean the Yamuna, starting with the Najafgarh Drain. The objective is clear: to improve water quality, reduce pollution levels, and bring the river closer to achieving the government’s target of “Zero Pollution.” The new DSTPs are designed to treat wastewater at the point of generation, preventing it from being discharged untreated into the drain and, ultimately, the river. The DJB’s efforts are being framed within the broader context of the “Sahibi Mission,” a dedicated initiative aimed at cleaning the Najafgarh Basin and improving water quality in the region. The Najafgarh Drain, often referred to as the erstwhile Sahibi River, is an extensive network of wastewater channels that serve as a major outlet for untreated sewage from various parts of Delhi. The drain is so large that it cannot be completely diverted or tapped; hence, the approach to cleaning it involves a combination of decentralised treatment plants and strategic water management. Officials from the DJB have pointed out that the sheer scale of the Najafgarh Drain – which is often likened to a small river due to its size – requires a distributed solution. By deploying multiple smaller treatment plants at key points, the goal is to treat sewage at the source, thereby mitigating pollution in the Yamuna and preventing untreated water from entering the river.
The DSTPs will be located in several critical locations across southwest Delhi, including areas like Jaffarpur, Galibpur, Khera Dabar, Hasanpur, Kazipur, Shikarpur, Sarangpur, Kair, Kakrola, Kangaheri, and Dichon Kalan. These plants will play a key role in addressing the pollution problem at its roots and will support the overall water quality management framework being laid out by the DJB. As part of the project’s conditions, the treated water from the DSTPs will meet stringent water quality standards. Specifically, the biochemical oxygen demand (BOD) and total suspended solids (TSS) levels in the treated water will be reduced to less than 10 milligrams per litre (mg/L). This is a significant improvement over the current BOD and TSS levels, which are estimated to be between 250-400 mg/L and 300-500 mg/L, respectively. BOD measures the oxygen consumed by microorganisms to break down organic matter, while TSS represents the solid particles suspended in water. Both are critical parameters that determine the quality of water and its impact on aquatic ecosystems.
In addition to the improvements in water quality, the treated water from the DSTPs will have several practical applications. The water can be used for non-potable purposes such as irrigation, rejuvenating water bodies, and supporting horticulture. This will not only aid in conserving freshwater resources but also help in managing urban water demands more sustainably. The project’s timeline is ambitious but feasible. The construction of these treatment plants is expected to take approximately 15 months, with an additional month allocated for commissioning the facilities. Another two months will be required for trial runs, ensuring that the systems operate efficiently and meet the prescribed environmental standards. The DJB has already initiated the bidding process, with the first phase of the project expected to be awarded within the next month.
As part of the government’s long-term plan to improve sewage treatment capacity across the city, the DJB is aiming to develop a total of 40 decentralised treatment plants (DSTPs) in various regions of Delhi. Fourteen of these will be located within the Najafgarh zone, and the first phase of work on 11 DSTPs has already commenced. In addition to this, a major development in the area is the construction of a 49.5 MLD centralised treatment plant in Chhawla, which will also form a critical part of the overall sewage management strategy. The financial and operational aspects of these projects are equally important. The government has approved an expenditure of Rs. 3,140 crore for setting up 27 DSTPs and associated infrastructure. The contract terms for these projects include a ten-year period for operation and maintenance, ensuring that the plants remain functional and efficient over the long term. By decentralising the sewage treatment process, Delhi is taking a proactive approach to wastewater management, moving away from the reliance on a few large, centralised treatment plants.
The initiative aligns with Delhi’s commitment to improving its environmental footprint and tackling pollution in a methodical and sustainable manner. The government’s focus on decentralised treatment facilities also resonates with the growing demand for localised solutions that can better address urban challenges like water management and waste disposal. Experts believe that these efforts could provide the much-needed solution to the mounting pollution levels in the Yamuna and improve the overall quality of life in Delhi. By reducing untreated sewage discharge, the government is not only working towards cleaner water but also ensuring a more sustainable urban ecosystem. As Delhi moves forward with these plans, the success of these initiatives will depend on strict monitoring, effective execution, and long-term commitment to water quality management.
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