Delhi plans to increase sewage treatment capacity to 95% by 2022: Report

Delhi will be able to treat around 95 percent of the wastewater by the end of the year, which will help reduce the pollution load in the Yamuna River, according to Delhi Jal Board's projections.

Delhi generates around 744 million gallons of sewage a day -- 80 percent of the 930 MGD water supply.

The 34 sewage treatment plants operational at 20 locations across Delhi can treat up to 597 MGD of sewage and have been utilising around 90 per cent (514 MGD) of their capacity.

Untapped wastewater from unauthorised colonies and jhuggi-jhopri clusters, and poor quality of treated wastewater discharged from WWTPs is the main reason behind high levels of pollution in the river.

According to a report submitted to the Union Jal Shakti Ministry, the Delhi Jal Board plans to augment its sewage treatment capacity by 130 MGD by December, 2022.

The treatment capacity will be increased by 20 MGD at the Kondli STP, 40 MGD at Rithala STP, 30 MGD at Okhla STP and 40 MGD at Coronation Pillar STP.

Thus, Delhi will be able to effectively treat 707 MGD (95 percent) of wastewater by the end of this year, it said.

The treatment capacity will be further increased to 903 MGD by June, 2023 to accommodate the future increase in sewage generation with the construction of 48 new STPs and decentralised STPs in outer Delhi, new STPs at Delhi Gate (10 MGD) and Sonia Vihar (7 MGD) and capacity augmentation of existing STPs through latest technology.

The construction of 48 new STPs and DSTPs in outer Delhi will increase the treatment capacity by 92 MGD and the DJB will be able to treat 87 MGD more wastewater after capacity augmentation of the existing STPs.

The DJB is also rehabilitating its existing STPs to meet the new standards for wastewater prescribed by the Delhi Pollution Control Committee.

Delhi generates around 720 million gallons of wastewater a day. The 35 STPs located at 20 locations across Delhi can treat up to 597 MGD of sewage and have been utilizing around 90 percent of their capacity.

According to the DPCC, biological oxygen demand, total suspended solids and total nitrogen in the treated wastewater should be 10 milligrams per litre or less.

Chemical oxygen demand should be less than 50 mg per litre, and ammoniacal nitrogen and phosphate should be below 5mg per litre and 2 mg per litre, respectively.

On an average, 24 out of the 34 STPs in the national capital did not meet the prescribed standards for wastewater over the last one year, according to government data.

Of the 13 common effluent treatment plants in industrial areas across Delhi, only six comply with the DPCC standards for wastewater on an average.