India and Denmark together launched a whitepaper recently on ‘Urban Wastewater Scenario in India’ at World Water Congress and Exhibition 2022 in Copenhagen. Data for 2020-21 indicates a sewage generation of 72,368 MLD in urban centres across the country, the installed sewage treatment capacity was only 31,841 MLD.
India and Denmark together launched a whitepaper recently on ‘Urban Wastewater Scenario in India’ at World Water Congress and Exhibition 2022 in Copenhagen. An interdisciplinary team was formed with partners from Government Knowledge agencies such as Atal Innovation Mission (AIM), NITI Aayog, Ministry of Jal Shakti and National Mission for Clean Ganga (NMCG), international agency Innovation Centre Denmark (ICDK) and Indian Institute of Technology Bombay (IITB) to develop the whitepaper. The whitepaper presents the current status of wastewater generation in India, future capacity, need for wastewater treatment, scope for improvement and augmentation in existing infrastructure and technologies, methods for public participatory approach, financing, and co-financing options among other things.
Rapid urbanization is adding pressure on freshwater sources
With the rapidly growing population in urban areas, water scarcity is a consequence in most areas because of the expansion at an unprecedented pace. There is added pressure on freshwater sources to meet the ever-growing demand for water in urban areas. To keep up with the rising demand, it is necessary that alternate water resources are identified. One such unconventional water resource is wastewater. The increased consumption of water and improved coverage in domestic water supply and sewage due to the expansion of urban population gives rise to increased quantities of wastewater, treatment, and utilization of which has an enormous potential for meeting the supply-demand gaps in these areas.
India generates the largest volumes of wastewater in South Asia
As per the ‘Urban Wastewater Scenario in India’, Asia generated the largest volumes of wastewater, about 42% (159 billion cubic metres) of the wastewater globally which is expected to increase to 44% by 2030. At the global level, only about 63% of the wastewater generated annually is collected, and only 52% treated. Only 11% of the total wastewater generated is reused annually and 22% of the treated water is reused directly. About 40% of the wastewater generated is discharged directly to the environment. Across regions, it was observed that wastewater collection and treatment was the highest in Western Europe and lowest in Southern Asia. India stands on the top in highest wastewater generation among the South Asian countries.
10 states account for 73% of the total sewage generated in 2020-21
As per the assessment by Central Pollution Control Board (CPCB), the sewage generation in the urban centres of India was 72,368 Million Litres per Day (MLD) for the year 2020-21. Maharashtra generated the highest quantity of sewage across states, with 9,107 MLD followed by Uttar Pradesh with 8,263 MLD. Tamil Nadu generated 6.421 MLD followed by West Bengal and Gujarat with more than 5000 MLD each. These five states together accounted for more than 47% of the sewage generated every day. Along with Karnataka, Kerala, Madhya Pradesh, Delhi, and Rajasthan, the 10 states together contributed to more than 73% of the total sewage generated at the national level. On the other side, the sewage generated in the Northeastern states of Tripura, Manipur, Nagaland, Meghalaya, and Mizoram was less than 200 MLD each while that by Sikkim and Arunachal Pradesh was less than 100 MLD each.
Only about 28% of the sewage is treated while the remaining is disposed of directly into water bodies
While the 2020-21 data indicates a sewage generation of 72,368 MLD in urban centres across the country, the installed sewage treatment capacity was only 31,841 MLD, which is about 43.9% of the sewage generated. Of this installed capacity, developed and operationalized capacity was only about 84%, which is 26,869 MLD. The actual utilized capacity was even lower. It accounted for 75% (20,235 MLD) of the total operationalized capacity. In simpler terms, only about 20,235 MLD of the total 72,368 MLD or 28% of the total sewage generated in urban centres is actually treated. The remaining 72% remains untreated and is disposed of into water bodies. Even if the proposed capacity of 4,827 MLD for sewage treatment is installed, there would still be a gap of 49% between the wastewater generated and the capacity available for treatment. This distribution is skewed across states.
In terms of installed capacity, Maharashtra’s installed capacity was 76% of the sewage generated. The state had the highest installed capacity with 6,890 MLD, followed by Gujarat, Uttar Pradesh, Delhi, and Karnataka with more than 2000 MLD each. The five states accounted for more than 60% of the installed capacity at the national level. Haryana, Madhya Pradesh, Tamil Nadu, Punjab, and Rajasthan had installed capacity of more than 1000 MLD each. The ten states accounted for 86% of the total installed capacity.
Many northeastern states do not have sewage treatment plants
As percentage of sewage generated, the installed capacity was more than 100% (more capacity than sewage generation) in Chandigarh, Himachal Pradesh, and Haryana. Punjab’s installed capacity was 94% followed by Delhi with 87% and Maharashtra with 76%. Despite being among the top five sewage generating states, Tamil Nadu’s installed capacity was only about 23% and West Bengal’s was 16% of the sewage generated. Assam, Manipur, Nagaland, Meghalaya, and Arunachal Pradesh did not have any sewage treatment plants. Despite generating 2,276 MLD sewage, the installed capacity was only 10 MLD in Bihar.
The actual quantity of sewage treated was also the highest in Maharashtra with more than 4000 MLD (47% of sewage generated in the state). Along with Gujarat, Uttar Pradesh, Delhi, Karnataka, Punjab, and Haryana, the 7 states alone were responsible for more than 80% of the actual sewage treated in the country though these states accounted for about 47% of the sewage generated.
Chandigarh had treated more sewage than it generated while Bihar, Assam & Kerala treated almost nothing
Chandigarh treated 125% of the waste generated. This could be because the actual utilized capacity is more than the sewage generation figures of the city which indicates that possibility of sewage coming from the adjoining cities or mixing of industrial wastewater into sewage. Delhi, Punjab, and Haryana treated more than 70% of the generated sewage while Gujarat treated 54% and Maharashtra treated 47%. Arunachal Pradesh, Bihar, Assam, Chhattisgarh, Jharkhand, Kerala, Manipur, Meghalaya, Mizoram, Nagaland, and Tripura treated only 0 to 1% of sewage generated while West Bengal and Odisha treated about 4% each.
There is no specific policy at the state or national level to deal with wastewater treatment
The data is a clear indication that sewage or wastewater treatment is not being given enough & uniform attention across the country. Urban Local Bodies (ULBs) are responsible for domestic wastewater treatment through provision and maintenance of wastewater treatment facilities in their administrative area. However, past audits by CAG have revealed that these facilities lack manpower, financial management, and monitoring and execution. The whitepaper highlighted the absence of specific policy at both the Central or State level that deals with prevention of pollution, treatment of polluted water and ecological restoration of polluted water bodies.
Moreover, the cost of violating the provisions of Water (Prevention and Control of Pollution) Act’ is much less than the cost of compliance. Apart from this, there are lacunae in the water quality monitoring system in the country with different standards set for different uses.
Further, there is a huge gap between generated sewage and treatment capacity as observed earlier. This gap is more in cities with lesser population since capital expenditure to set STPs is high. The high cost and limited budgets hinder the adoption of latest technology to handle wastewater. Encouraging people to use recycled water for daily purposes is another challenge. There is also hesitance on the side of people to use recycled water owing to health concerns.
Whitepaper calls for formulation of coordinating agency at different levels
The ‘Urban Wastewater Scenario in India’ whitepaper suggests utilization of decentralized wastewater treatment systems to make wastewater recycling more accessible. The paper also advocates for treating the wastewater near the site reducing the risks associated transportation. Some other innovative, cost-effective, and sustainable solutions suggested in the white paper include nature-based solutions such as floating treatment wetlands, green roofs and living walls, waste stabilization ponds, vermifiltration, etc. It also calls for public-private partnerships, community participation & performance evaluation of treatment plants, public awareness, trainings, and knowledge transfers, improved institutional and international collaboration, and collaboration with NGOs. The paper also suggests the formation of a coordinating agency for managing the efforts at the municipal/state/national level.
Featured Image: Urban Wastewater in India