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

Context : Several Indian cities are facing increasing water stress due to heatwaves, high evaporation and rising demand. The article advocates the reuse of treated wastewater (domestic sewage), especially for non-potable purposes.

Prelims : 

• India’s annual per capita water availability is projected to decline from about 1,500 m³ to below 1,200 m³ by 2050.
• A per capita availability below 1,000 m³ is considered water scarcity.
• Non-potable uses include: Irrigation of horticultural crops, Landscaping, Construction, Public conveniences, Textile manufacturing, Lake rejuvenation
• According to CEEW, a circular water economy could unlock an investment opportunity worth over ₹3 lakh crore and generate about 1,00,000 additional jobs by 2047.
• Around 14 Indian States have water reuse policies. Uttarakhand, Uttar Pradesh and Odisha are among the latest States to notify reuse policies.
• Less than 50% of India’s sewage treatment capacity is utilised, and less than one-third of treated wastewater was reused in 2021.
• Reuse remains a small proportion of the total treated wastewater volume. India has adopted a Zero Liquid Discharge (ZLD) policy for industries.
• Cities in Gujarat provide financial assistance to industries for setting up ZLD systems. The Central Pollution Control Board (CPCB) prescribes effluent discharge quality standards.

Mains :  

1. Urban Water Stress

• Rising temperatures and declining per capita water availability are intensifying urban water shortages.
• Indian cities need alternative water sources to bridge demand-supply gaps.

2. Wastewater Reuse

• The article identifies treated wastewater reuse as a major untapped resource.
• Reuse can reduce freshwater demand for non-potable applications.

3. Institutional and Infrastructure Gaps

• Limited treatment infrastructure and operational constraints hinder reuse.
• Greater public and private investment is needed in reuse infrastructure.

4. Policy and Governance Reforms

• Cities require dedicated reuse plans suited to local conditions.
• Institutional, financial and behavioural reforms are necessary to promote a circular water economy.

5. Industrial Water Management

• Stronger enforcement of ZLD norms can improve industrial water reuse.
• Incentives can encourage industries to adopt reuse technologies.