Delhi announced on Monday that a proposal to reuse highly treated wastewater to increase its water supply has been approved after two years of discussions by the Upper Yamuna River Board (UYRB), reports The Times of India.
“It took us a lot of effort to convince UYRB about the significance of the project. [The state of] Haryana still has objections, but it is our internal project,” said a Delhi Jal Board official to the media. The Delhi Jal Board is responsible for meeting the needs of potable water in the National Capital Territory of Delhi.
Delhi chief minister Arvind Kejriwal, who was the Delhi Jal Board chairman in 2018 had announced in July of that year a project in line with Singapore’s NEWater to use treated wastewater to revive the Yamuna river. According to the chief minister, 150 MGD (Million gallons per day) of treated water would be used to increase the 900 MGD capacity of Delhi.
In 2018, a Times of India report had found that this project to use treated water would increase the city’s water supply by 15-20%.
Although the UYRB has approved the measure, it has toughened the norms for treated water. The entity stated that “Instead of biological oxygen demand to total suspended solids ratio of 10:10, the treated water from Coronation Pillar plant will be further purified with the use of advanced technology of microfiltration to 3:3 levels, which is Class C level for clean inland surface water level.”
For ecological purposes, the Upper Yamuna River Board (UYRB) has also ordered the Delhi Jal Board to take a maximum of 80 per cent of the treated wastewater released into river Yamuna at Palla.
The Delhi Jal Board is currently constructing Asia’s biggest sewage treatment plant to produce high quality treated water with BOD and TSS levels of 10 and 10. “The national norm for treated effluent dumped in rivers is 20:20. We will now further improve the water quality 3:3 level,” added the DJB official.
According to the Delhi Jal Board, the project could take up to two years to set up.