Hindu Sustainability Summit: “Treat Wastewater as an Economic Resource”

It was the acute water shortage in Chennai in 1980 that proved to be a turning point for Chennai Petroleum Corporation Limited (CPCL)’s attitude towards used water, a shift away from reliance on Metro Water towards the principles of reduction, reuse and recycling, as stated by P. Kannan, Director (Operations), CPCL.

He was one of the leading companies and experts who made the case for treating wastewater as a valuable economic resource at the Hindu Sustainability Summit 2026 on Wednesday (23 September 2026). The discussion on “Reimagining Water Management for a Circular Future” was moderated by K. Lakshmi, Deputy Editor, The Hindu.

“We have optimized our water requirements and taken several measures to reduce consumption. For reuse, water is diverted to our processing units and wherever possible we have maximized our reuse capability. We also generate 480 tonnes of steam as part of our recycling efforts,” Mr Kannan said.

Replacing fresh water with treated water

Indian Oil Corporation Limited is another oil company that is changing the way it does business. “We operate nine refineries. Geographically, there are certain things you cannot avoid. Refineries that are inland face challenges in reducing their water footprint. We recycle almost 90% to 91% of our wastewater, but we don’t stop there,” said IOCL Managing Director Mukesh Mohan.

“We are looking at replacing the fresh water used in our process units with treated water from sewage treatment plants (STP) in the city. In major cities like Vadodara and Guwahati and refineries in Mathura and Panipat, we have clear, concrete plans to partially replace our fresh water supply with STP treated water,” Mr. Mohan added. He noted that this requires the support of the municipality and the WWTP must be designed to treat wastewater from nearby households and industrial units.

The desalination myth

Rajiv Mittal, Chairman and CEO of VA TECH WABAG Limited, said fresh water is not the answer to everything. “We have a huge coastline in Chennai. Why don’t we use seawater? You don’t want to drink recycled sewage, but why not use seawater?” he asked. “There is a myth that seawater desalination is expensive. I believe that water management is more important. And we should have a responsibility to conserve water,” he added.

Mr. Mittal said untreated water should not be released. “The only way to make this possible is to treat wastewater as an economic resource. If you label wastewater as an economic resource, people will treat it differently. You’re not throwing your money on the streets, so you’re not throwing wastewater on the streets or in landfills. You’re going to collect it, treat it, and create wealth from it.” he explained.

Groundwater monitoring

Rajesh Nair, a professor in the Department of Ocean Engineering at the Indian Institute of Technology, Madras, highlighted how they get geothermal energy from the Earth’s subsurface. “We are on India’s first project to extract geothermal energy from unused oil and gas wells… those that have been depleted,” he said.

Mr. Nair added that the quality of ground water needs to be assessed and different grades fixed. He stressed the need to monitor how groundwater conditions change over time, adding that more attention needs to be paid to protecting wetlands.

“We need data integration and digital data analysis. Only when we have data, we can manage things effectively. We should use Internet of Things (IoT) and AI-based solutions and integrate them under a common platform or one body that can provide clear guidelines on what water should be used for what purpose, how much water needs to be recharged in the groundwater system and so on. This way we can manage our water resources much more efficiently,” said Nair.

The Summit is supported by Chennai Petroleum Corporation Limited (CPCL) as Presenting Partner, with NLC India Limited, Larsen & Toubro (L&T), Navin’s, WABAG, Tamil Nadu Newsprint and Papers Limited, Indian Bank, Urbando and State Bank of India as Associate Partners.

The summit’s sustainability partnerships include Thermax as Sustainable Cooling Partner, Treeni as Intelligence Sustainability Partner, Chennai Port Authority as Blue Economy Partner and Tamil Nadu Green Climate Company as Climate Action Partner.

Mangaldeep is the Perfume Partner, Puthiya Thalaimurai the TV Partner, Federal the Digital TV Partner and Communitree the NGO Partner.

Published – 23 Sep 2026 23:02 IST