A staggering 72 per cent of India’s urban wastewater remains untreated, presenting both a challenge and an opportunity for addressing the nation’s growing water crisis.
The reuse of treated wastewater could significantly ease water shortages in urban areas, according to the report Waste to Worth: Managing India’s Urban Water Crisis through Wastewater Reuse, released jointly by the Centre for Science and Environment (CSE) and the National Mission for Clean Ganga (NMCG).
The report, unveiled at a national workshop co-organised by CSE and NMCG under the Union Ministry of Jal Shakti (water resources), highlights the potential of wastewater reuse to mitigate water scarcity caused by rapid urbanisation, industrial expansion and climate change. Speaking at the event, Sunita Narain, director-general of CSE, stressed the critical need to adopt wastewater reuse as a sustainable strategy.
“India faces significant water scarcity challenges due to rapid urbanisation, industrial growth, population expansion — and most importantly — climate change. Wastewater reuse can be a key part of the strategy to address these concerns and promote water circularity and sustainability,” Narain said. She described the report’s focus on turning “wastewater into water again” as essential for achieving water security.
India currently treats only 28 per cent of the 72,000 million litres of wastewater generated daily. The remaining untreated water pollutes rivers, lakes and soil. CSE’s report underscored the potential of treated wastewater as a resource for irrigation, industry, and urban greening.
The Ministry of Jal Shakti mandates that cities recycle at least 20 per cent of the water they consume, but achieving this target will require significant scaling up of treatment infrastructure.
Rajiv Kumar Mital, director-general of NMCG, emphasised the importance of maximising treated wastewater's potential. “Using and disposing treated water, without harnessing its potential, means we are losing out on utilising an important resource. The challenge is to scale up and ensure that the work we do in this sector is impactful,” he said.
Regional disparities in wastewater treatment and reuse make the process challenging. Uttar Pradesh leads in untreated wastewater volumes, followed by Maharashtra, Karnataka, Rajasthan, Tamil Nadu, Delhi and Haryana. However, several states have implemented progressive policies.
Maharashtra requires industries in urban areas to use treated wastewater, while Gujarat targets 100 per cent reuse in agriculture and industry. Tamil Nadu has prioritised industrial and urban greening applications.
Cities such as Nagpur, Bengaluru and Chennai offer successful examples of wastewater reuse. Nagpur supplies treated wastewater to power plants, reducing freshwater consumption.
Bengaluru uses it for agriculture, lake rejuvenation and groundwater recharge. Chennai incorporates treated wastewater into industrial processes, urban landscaping and groundwater replenishment.
“Aligning policies with urban planning and industrial needs can enhance adoption,” said Subrata Chakraborty, senior programme manager of CSE’s water programme. He also emphasised the need for decentralised and cost-effective treatment technologies to overcome infrastructure gaps.
While the benefits of wastewater reuse are clear, several obstacles remain. Public resistance, driven by cultural beliefs and safety concerns, poses a challenge. Infrastructure deficits, quality assurance and high operational costs further complicate efforts to scale up wastewater reuse.
“Upscaling wastewater reuse faces challenges, including infrastructure gaps in sewage treatment and distribution, quality assurance to meet reuse standards, public resistance due to cultural beliefs, and the high operational costs of treatment facilities,” explained Sumita Singhal, programme manager for water at CSE. She added that effective public-private partnerships and capacity-building initiatives could address these issues and promote widespread adoption.
The report also stressed the importance of fostering a circular economy to manage freshwater demand sustainably. By integrating wastewater reuse into programmes like the Jal Jeevan Mission, Atal Bhujal Yojana and AMRUT, India can build a more climate-resilient water management framework.
Based on a detailed analysis of 35 case studies across 16 cities in seven states, the report serves as a blueprint for policymakers and practitioners. It advocates for prioritising wastewater reuse as a public good, while ensuring equity for underserved communities.
“The urgency of water scarcity demands a fresh perspective on how we prioritize and utilise treated wastewater as a new and vital water resource,” said Chakraborty.
The report underscored the need to view treated wastewater not as a waste product but as a valuable resource critical to India’s water security.
Achieving sustainable water management will require innovative policies, community engagement and robust infrastructure investment, the report highlighted.