Untreated sewage, lack of effluent plants behind Yamuna’s pollution: Centre in Parl

Despite the Delhi Jal Board spending Rs 5,536 crore on cleaning the Yamuna in the past three years, the river continues to carry high pollution levels inside. A written reply in the Rajya Sabha on Monday explains the factors that keep the river polluted.

According to the Ministry of Jal Shakti, the river enters Delhi at Palla village with water quality within the prescribed limits. Data from the Central Pollution Control Board and the Delhi Pollution Control Committee shows that between January and September 2025, biochemical oxygen demand (BOD) levels ranged between 2.5 and 4 mg/l and dissolved oxygen (DO) levels between 6 and 9.5 mg/l, which meet the standards for a healthy river. However, the river’s condition deteriorates sharply as it flows through the city.

The ministry states that the discharge of untreated and partially treated sewage remains the biggest contributor to pollution. In August 2025, the gap in sewage treatment stood at 414 megaliters per day (MLD), meaning a significant portion of the city’s wastewater enters the river without adequate treatment.

Industrial pollution also continues to add to the load. Several approved industrial zones in Delhi still do not have common effluent treatment plants (CETPs). Wastewater from these areas flows into drains that eventually meet the Yamuna.

Delays in sewage infrastructure further slowdown the clean-up process. Work on new sewage treatment plants, along with the rehabilitation and upgrade of older facilities, remains incomplete, the ministry says. Until these projects are finished, untreated sewage continues to reach the river.

Solid waste is another pressure point. Delhi generates 11,862 tonnes of waste per day, but the treatment capacity is only 7,641 tonnes, leaving a shortfall of 4,221 tonnes. A portion of this unmanaged waste ends up in drains and on the riverbanks.

The government informed the Parliament that the National Mission for Clean Ganga has sanctioned 35 projects for Yamuna rejuvenation under the Namami Gange programme. These projects aim to add 2,243 MLD of sewage treatment capacity at an estimated cost of Rs 6,534 crore. So far, 21 projects have been completed, while others remain under construction.

The reply indicates that though funds are being spent, key systems required to clean the Yamuna such as sewage treatment, industrial effluent management and solid waste processing are still not fully in place. As a result, the river continues to carry a high pollution load through the Capital.

'No study on health risks from polluted rivers'

• The Union Government is not conducting any recent study on health risks from polluted rivers.
• States, Union Territories and local bodies are responsible for preventing untreated sewage and industrial effluents.
• India has 4,493 grossly polluting industries, with 3,633 operational.
• CPCB’s latest assessment of 623 rivers found 296 polluted stretches across 32 states and UTs.
• Industries are required to install treatment plants under environmental laws.