Significant delay in several major Yamuna cleaning projects in Delhi: Govt report

New Delhi: Several major projects aimed at cleaning the Yamuna river in Delhi are reported to be running behind schedule, according to a recent Delhi Pollution Control Committee (DPCC) report.

The report, submitted to the National Green Tribunal (NGT), highlights significant delays in projects undertaken by the Delhi Jal Board (DJB) and the Delhi Development Authority (DDA) to reduce pollution in the river.

The projects include the construction of new sewage treatment plants (STPs), rehabilitation of existing ones, trapping of drains, laying sewer lines in unauthorised colonies, desilting of trunk sewers and utilisation of treated wastewater. These initiatives are part of an NGT panel's "Action Plan to Rejuvenate Yamuna".

According to the DPCC report, the work by the DDA to restore the Yamuna floodplains, divided into several sections, has been delayed by six to 12 months.

The report reveals that the construction of a new 124 million gallons per day (MGD) STP in Okhla has been delayed by nine months and it is now expected to be completed by March next year. Similarly, the construction of a 7 MGD STP in Sonia Vihar has been delayed by four months, with a new completion target set for the end of 2023.

The 22-kilometre stretch of the Yamuna between Wazirabad and Okhla, which represents less than two per cent of the river's total length, accounts for approximately 75 per cent of its pollution load.

High levels of pollution in the river are attributed to untreated wastewater from unauthorised colonies and jhuggi-jhopri clusters, as well as the poor quality of treated wastewater discharged from STPs and common effluent treatment plants.

The Delhi government has made a commitment to clean the Yamuna to bathing standards by February 2025. To meet these standards, the biochemical oxygen demand (BOD) should be less than three milligrams per litre and dissolved oxygen (DO) should be greater than five milligrams per litre.

Currently, Delhi generates 792 MGD of sewage and 35 STPs across the city can treat up to 667 MGD of sewage, utilising around 70 per cent of their capacity (550 MGD). Around 242 MGD of sewage directly enters the river.

Government data indicates that only 10 out of the 35 operational STPs in the capital meet the prescribed standards for wastewater (BOD and Total Suspended Solids less than 10 milligrams per litre), with the capacity to treat 150 million gallons of wastewater per day.

The DJB is in the process of upgrading and rehabilitating existing STPs to meet the prescribed norms and reduce the pollution load in the Yamuna.

While the DJB initially pledged to increase the sewage treatment capacity to 814 MGD by December this year, the deadline has been extended to June 2024, the DPCC report submitted to the NGT showed.

Similarly, the deadline for achieving a sewage treatment capacity of 964 MGD by June 2024 has been changed to December 2024.

The report indicates that the rehabilitation and upgrading of the existing STPs at Rithala, Kondli and Yamuna Vihar have been delayed by three to nine months.

The efforts to trap some major drains and sub-drains are running six months behind schedule. Similarly, the desilting of the sewer trunk and the laying of the sewer network in unauthorised colonies have surpassed the deadline.