New Delhi, May 25 -- The Delhi Jal Board (DJB) has awarded work for 12 new decentralised sewage treatment plants (DSTPs) in the Najafgarh area as part of efforts to improve sewage management and clean the Yamuna, officials said. The project, with a combined treatment capacity of 46.5 million gallons per day (mgd), is estimated to cost around Rs.860 crore and is being funded under Atal Mission for Rejuvenation and Urban Transformation scheme - a central government initiative. DSTP is the system that treats wastewater at the source. The Najafgarh drain is the largest source of pollution in the Yamuna, accounting for 60% to 70% of the total wastewater and pollution entering the river. As per officials, DSTPs will help reduce untreated sewage flowing into the Najafgarh drain and improve water quality in Yamuna, a key project of the BJP-led Delhi government. Delhi water minister Parvesh Verma said that a large number of colonies and villages in Najafgarh still discharge untreated sewage directly into the drain, which ultimately flows into Yamuna. "Our focus is on creating long-term infrastructure that improves sewage treatment capacity, prevents untreated wastewater from entering drains and ensures better basic services for residents in outer Delhi areas," Verma said. He said the cost includes not only the construction of the plants but also their operation and maintenance for the next 15 years, for which the executing firm will be fully responsible. Among the DSTPs awarded is the Mitraon DSTP with a capacity of 17 mgd, expected to benefit 81 unauthorised colonies and around 0.36 million people. Another package includes four DSTPs at Kair, Kanganheri, Kakrola and Dichaon Kalan, which are expected to benefit 29 colonies, five villages, and 0.22 million people. Three additional DSTPs at Galibpur, Sarangpur and Shikarpur are also part of the plan and will benefit 11 villages and around 42,000 residents. A fourth package includes plants at Hasanpur, Jaffarpur, Kazipur and Khera Dabar, covering 16 villages, nine unauthorised colonies and 62,000 people....