Expert: Bengaluru will never be thirsty if it stops saying ‘disgusting’ about treated wastewater

BENGALURU: Back in 2016, the Center for Ecological Sciences (CES) at the Indian Institute of Science, Bengaluru, found a way to keep water surplus in its IT centre. The CES technical report states that the average household requires 20.05 TMC (thousand cubic feet) of water per year. The report states that about 16.04 TMC, or about 80%, of this amount can be satisfied by just treating sewage. Apart from this, Bengaluru receives about 14.80 TMC of rainfall annually and can easily meet its water needs, the report said.

Cut to 2023. Little did they know, it would take them nearly six months to convince others.

They didn’t agree until the company installing the wastewater treatment equipment made it clear in the agreement that it would purchase all the treated water. Many people strongly disagree with using a drop of treated water within the complex. Don’t forget to drink water, said Gopidas, an Amazon software engineer who lives in Emanuel Heights. They don’t even need treated water to water their plants because they have Tulsi plants.

S Vishwanath, Bengaluru-based water expert and director of Biome Environmental Solutions, is a long-time advocate of treating wastewater for drinking. According to him, it’s all in the mind now because science has shown that drinking treated wastewater is perfectly fine.

People find it difficult to accept what they consider sewage. Most of the arguments against it stem from ignorance. Vishwanath told PTI that science has advanced enough for us to drink treated wastewater without causing any health issues.

A little more than 10 days ago, investment wizard Nithin Kamath (founder and CEO of Zerodha and Rainmatter Foundation) backed Boson White Water, a Bengaluru-based company that converts wastewater into drinking water, and said wastewater could be part of Bengaluru’s solution, though some People agree with him, but most are repelled by the idea of ​​drinking water that was once sewage.

People began replying to Camas saying, without any scientific basis, that the treated water contained heavy metals or hormones and was therefore unfit for drinking. This concern also stems from the perception that wastewater treatment plants are being run in a very poor manner.

Vikas Brahmavar, co-founder of the startup Boson White Water, said they received a large number of calls after the promotional video forwarded by Camas went viral on the Internet.

In one day, we received over 300 calls. “We’ve been doing this for two years and we get up to a dozen calls a day,” Brahmavar said. PTI.

But Brahmavar said much of it was an attempt to reiterate that wastewater, whether treated or not, is smelly and dirty.

We have come a long way in the past two years. But we haven’t convinced people to drink wastewater yet. It will take some time to break through this psychological barrier. What people don’t understand is that the moment we start relying on water tankers for water, we’re past the dirty water curve. Who knows where they got the water from, Brahmawal said.

People also don’t realize that treated wastewater is being consumed indirectly, Vishwanath said.

He pointed out that the Lakshmi Sagara Lake in Kolar is the first of the 82 lakes in Kolar and Chikkaballapur districts to be filled up with STP treated effluent and is the first of its kind in Kolar. -Part of the Chalaghatta (KC) Valley Project, under which the government plans to fill up 134 lakes at a cost of Rs 1,342 crore.

Viswanath said the scheme is one of the first in India to formally use such large amounts of secondary treated wastewater to fill water tanks and river ecosystems and provide water for agriculture.

He said a June 2021 study by his organization, the Biome Environment Trust, on the impact of the scheme among local people, mainly farmers, found that treated water-filled lakes and tanks could increase boreholes. output.

In Lakshmi Sagara, for example, water levels rose in open wells within three months of the lake filling with treated wastewater, and in drilled wells within six months. He said farmers here now farm year-round.

In the Biome report, farmers interviewed by the researchers confirmed that, contrary to negative assumptions that had previously delayed the program, they found that the work rejuvenated depleted groundwater, and that most found it at depths of 300 to 400 feet. Earlier it was difficult to find water even at a height of 1,200 feet, they said, adding that they often dug two to four wells as the previous wells failed to produce water.

In India, one estimate suggests that treated wastewater can irrigate approximately 1 to 1.5 million hectares of land annually. I believe proper hydrogeological and aquifer mapping studies are needed to better determine the impacts on recharge.

“But this is the only way we can reduce our dependence on rainwater. I also think that if people start adapting to non-potable uses, drinking water will follow. It’s just a matter of time,” Viswanath said.