By 2021, Delhi may make waste water drinkable

DELHI PRODUCES AROUND 916 MILLION GALLONS PER DAY OF WATER, OF WHICH ONLY AROUND 80 MGD COMES FROM GROUNDWATER

NEW DELHI: The national capital may soon get its own version of Singapore’s NEWater, essentially sewage treated to make it potable and if all goes well, it could soon augment its existing water supply by a fifth.

“We will reuse water. Water from a sewage treatment plant will be released into the Yamuna, right where the river enters the city. Downstream, we will lift the river water and send it to a water treatment plant for further treatment. This treated water will be supplied to Delhiites,” said Dinesh Mohaniya, vice chairman of Delhi Jal Board.

A Jal Board officer said on condition of anonymity that releasing water into the river would help increase the volume of the river and maintain its ecological flow. “It will also help us overcome the mental block that we are drinking sewage,” he added.

Last week, government thinktank NITI Aayog released a report warning that 21 cities, including Delhi, will run out of groundwater by 2020, affecting 100 million people.

Currently, Delhi produces around 916 MGD (million gallons per day) of water, roughly 3.5 billion litres, out of which only around 80 MGD comes from groundwater. The rest, which comes from the Yamuna and the Ganga, is treated and supplied to consumers. The water utility now plans to increase its production capacity by around 200 MGD by the year 2021. The city needs around 1,100 MGD.

Experts welcome the proposal but said that the entire effort of treating water at sewage treat- ment plants would go to waste if it is released back into the river.

“While on one hand you are treating water at a sewage plant, on the other, you are releasing it into the Yamuna, which has almost become like a drain over the years,” said SK Singh, head of the environmental engineering department at Delhi Technical University, and a specialist in waste water treatment designs.

“The entire effort goes to waste as the treated water when it mixes with polluted river water would become polluted again. Instead they could directly send the water from the sewage treatment plant to the water treatment plant ,” said Singh said.

Releasing water from a sewage plant into the river is a bad idea, said an activist.

Manoj Misra of Yamuna Jiye Abhiyan said: “The Jal Board should first ensure that all its sewage treatment plants s are functioning at their optimum capacity. They must use that treated water for meeting the non-drinking water needs of the city. The National Green Tribunal permitted DJB to release not more than 3% of treated sewage water into the river. For rejuvenation the river will need its own environmental flow and not water from a sewage treatment plant.”