India’s water resources are under severe stress, largely as a result of over-exploitation and pollution. It is estimated for example that only 30% of sewage from major cities and 60% of industrial wastewater, mostly from large-scale industries, receives treatment.

“Discharge of untreated wastewater has resulted in contamination of 75% of all surface water bodies in India,” explains PAVITRA GANGA project coordinator Paul Campling from the Flemish Institute for Technological Research (VITO) in Belgium. “At the same time that water quality is deteriorating, demand for water resources in a rapidly growing population and transitioning economy is projected to increase dramatically.”

This is an enormous challenge, says Campling, and will require a move away from today’s linear ‘take-use-waste’ approach to resources, and towards more circular water management.

"One of the measures to reduce pressures on freshwater resources is to use partially treated or untreated waste water for irrigation, but we have to make sure that water reuse is safe and sustainable,” he adds.

Improving wastewater treatment

To this end, the Indian government has started an ambitious programme of works to improve wastewater treatment, called Namami Gange. The PAVITRA GANGA project links directly to this programme and builds on existing cooperation between the EU and India.

“PAVITRA GANGA is focused in particular on finding cost-effective and energy-efficient solutions for the treatment of unregulated drains, and improving existing wastewater treatment installations,” explains Campling.

Central to this has been the establishment of pilot sites, installed with local stakeholders and industrial partners. These include the trial of a new approach to anaerobic digestion by combining concentrated sewage with other organic waste streams and also a low-cost, low-energy alternative to aerobic membrane reactors at the Jajmau Urban Wastewater Treatment Plant in Kanpur. Another pilot site is assessing the impact of using photoactivated sludge systems to deal with unregulated sewage in the open drains of Delhi.

“These trials help us to evaluate the performance of innovative wastewater treatments, and resource recovery technologies in typical Indian conditions,” says Campling.

“The main purpose is to validate these technologies and approaches in India. But we are also assessing the policy and governance structures that have an impact on wastewater treatment and reuse practices.”

The project is evaluating smart water management tools such as mobile sensors to identify and map out pollution hotspots. Such monitoring technologies can be used to analyse the potential impact and efficacy of new wastewater treatment and resource recovery technologies. Citizen-based, participatory monitoring of basic water quality parameters at three villages close to Kanpur was carried out in March 2022.

This particular exercise taps into another key objective of the project – to fully involve local stakeholders in identifying both water-related challenges and solutions. “In Kanpur, we are engaging with farmers using partially treated wastewater for irrigation,” explains Campling.

“It is clear for them that wastewater safety aspects are particularly pertinent, especially the impact on their personal health and also on the soil and agricultural productivity. This shows that downstream impacts of wastewater reuse need to be addressed in an integrated manner.”

Circular economy approach

Results have shown that the technologies and monitoring services piloted by the project are performing to expected levels, helping to improve wastewater treatment and achieve resource efficiencies.

Campling firmly believes that Indian science institution and technology partners are crucial to fully maximising the relevance of this work, while the involvement of local stakeholders helps to better understand the current situation, adjust approaches accordingly and ultimately ensure acceptance on the ground.

An important next step will be to complete the full performance evaluation of the treatment technologies and smart water management approaches and then bring these to the market. As part of this process, Indian water professionals will be trained, to facilitate the adoption of these technologies.

The project will also establish an EU-India business platform, to ensure future market uptake and business development of the demonstrated technologies and services.

“We hope that given the benefits of adopting a circular economy approach to wastewater treatment, water reuse and resources recovery, this becomes the modus operandi for decision makers in India,” adds Campling.

“At the same time, it is clear that achieving the objectives of the Namami Gange programme is likely to take decades rather than years. In that sense, the tools, technologies and approaches demonstrated in PAVITRA GANGA should be an inspiration for water practitioners to adopt and develop further.”