According to Environment department records, there has been a marginal increase in Delhi's utilisation of installed sewage treatment capacity over the last three years – rising from 74.2% in 2022 to 79.16% in 2024, and reaching 80.9% in 2025. Seeking to tackle the single largest source of pollution entering Yamuna river, the Delhi Jal Board (DJB) on Wednesday approved sewerage and wastewater treatment projects worth around Rs 4,500 crore, including setting up of 15 decentralised sewage treatment plants (DSTPs), covering 1,000 km of sewer lines and upgrading existing treatment infrastructure. “These projects are expected to benefit around 20 lakh residents,” said Water Minister Parvesh Sahib Singh, adding that the work is set to be completed within 21 months. In a statement, the government said the new plants will cater largely to areas where sewer infrastructure remains inadequate. While the city has steadily expanded its sewage treatment capacity over the years, large volumes of wastewater still enter drains – either because many colonies remain unconnected to the sewer network or sewage has to travel a long distance before reaching treatment plants.