Our parched cities need to make every drop count, recycle water, Pg10

Key Highlights:

• Indian cities, including Narsinghpur, Ahmedabad, and Barmer, recorded temperatures above 40°C in early May, leading to severe water scarcity.
• India's annual per capita water availability is projected to decline from approximately 1,500 m3 to below 1,200 m3 by 2050, approaching the water scarcity threshold of 1,000 m3.
• Reusing treated wastewater for non-potable purposes could generate a market and investment opportunity exceeding Rs 3 lakh crore and create 1,00,000 additional jobs by 2047.
• The Council on Energy, Environment and Water (CEEW) analysis underscores the significant economic potential of a circular water economy.
• Key interventions proposed include city-specific reuse plans, private financing, improved Sewage Treatment Plant (STP) functionality, and a National Circular Water Mission.

Detailed Insights:

• High evaporation rates and increased domestic demand, exacerbated by heatwaves, are primary drivers of urban water stress.
• Many smaller cities now rely on private tanker water supply, while larger cities like Delhi source water from distant, upper riparian regions, increasing costs.
• Currently, less than 50% of urban areas have networked sewage treatment capacity, and less than one-third of collected sewage was treated in 2021.
• Private investments are crucial to enhance wastewater treatment and reuse infrastructure, complementing existing public funding.
• The Hybrid Annuity Model, successfully adopted by the National Mission for Clean Ganga, can effectively share financial risks between government and private developers.
• Many STPs fail to meet effluent discharge quality standards set by the Central Pollution Control Board (CPCB) due to poor maintenance and industrial effluent mixing.
• Industrial effluents containing heavy metals and toxins impair biological treatment processes in STPs by harming microorganisms.
• Despite India's Zero Liquid Discharge (ZLD) policy for industries, many small-scale units often violate norms by releasing untreated wastewater.
• A National Circular Water Mission aims to transform water management from a linear 'use-and-dispose' approach to a restorative, reuse-focused model.
• This mission necessitates technological, institutional, financial, and behavioural reforms to build water resilience.
• The Economic Survey of India 2025-26 and the study 'Water, Nature, Progress' have provided a roadmap for this circular water mission.
• Achieving a circular water economy is considered vital for India's journey towards becoming a developed nation under Viksit Bharat by 2047.

Key Concepts Involved:

• Water Scarcity Threshold: A condition where annual per capita water availability falls below 1,000 cubic meters.
• Circular Water Economy: A restorative model of water management that maximizes reuse and recycling of water resources, minimizing waste.
• Hybrid Annuity Model (HAM): A public-private partnership model where the government provides a fixed annuity payment to the private developer over the project's operational period, sharing financial risk.
• Zero Liquid Discharge (ZLD): An advanced wastewater treatment process that aims to recover and reuse all water, eliminating the discharge of liquid waste into the environment.