Wastewater is a reliable and cost-effective source of freshwater, particularly for agricultural applications, but remains an untapped and undervalued resource in India informs this White paper titled 'Urban Wastewater scenario in India' by Indian Institute of Technology Bombay (IITB), Atal Innovation Mission (AIM) -NITI Aayog, Innovation Centre Denmark (ICDK) and Ministry of Jal Shakti and National Mission for Clean Ganga (NMCG) in August 2022.

Wastewater treatment improves the quality of used water sources and makes water reusable by reducing contaminants to safe levels. However, much of the wastewater that is currently re-used is untreated or inadequately treated while the demand for clean water is increasing. The primary challenge is promoting wastewater re-use and safety – both for humans and ecosystems and ensuring that wastewater is adequately treated prior to use.

Sewage generation in urban India  

According to Central Pollution Control Board (CPCB) figures, 72,368 Million Litres per Day (MLD) of sewage was generated in urban areas in India in 2020-21. Currently, the installed sewage treatment capacity is 31,841 MLD while the operational capacity is 26,869 MLD, which is much lower than the load generated. Of the total urban sewage generated, only 28 percent (20,236 MLD) is treated while 72 percent remains untreated and is disposed off in rivers, lakes, and aquifers leading to contamination and deterioration of water quality. 

Urbanisation has been predicted to further increase the amount of wastewater generated in cities and increase pressure on the available freshwater resources. This white paper reviews the current scenario of urban wastewater management in India, treatment and reuse solutions and how one can adapt those as per the requirements of land, natural resources, energy, cost and in the context of specific laws and regulations in the Indian context.

Current scenario of Urban Wastewater Management (UWM) in India 

There is no specific Act dedicated to management of wastewater in India, but there are provisions in the Water (Prevention and Control of Pollution) Act, 1974 which deals with wastewater as a source of pollution. The Central and State Pollution Control Boards established under this Act are responsible for the prevention and control of water pollution. There are penal provisions regarding pollution in water flowing into the streams, wells, sewer, or land. The Central Pollution Control Board (CPCB) prescribes the criteria as ‘Water Quality Standards’ and ‘Industrial Effluents Standards’ which need to be constantly updated using international standards and considering emergent pollutants. 

The municipal laws impose obligations on wastewater disposal into drinking water sources and include The Water (Prevention and Control of Pollution) Cess Act, 1977; The Environment (Protection) Act, 1986; The National Environment Policy, 2006; National Urban Sanitation Policy, 2008; India’s National Water Policy, 2012; National Faecal Sludge and Septage Management Policy, 2017; The Model Bill for Regulation of Groundwater Development 2016; The Prohibition of Employment as Manual Scavengers and their Rehabilitation Act, 2013; The Coastal Regulation Zone Notification; The National Water Mission; The National Water Quality Monitoring Programme of India; The National Guidelines on Zero Liquid Discharge developed by CPCB etc.

The National Framework on the Safe Reuse of Treated Water, 2021 recommends the need for "widespread and safe reuse of treated used water in India that reduces the pressure on scarce freshwater resources, reduces pollution of the environment and risks to public health, and achieves socio-economic benefits by adopting a sustainable circular economy approach”.

Institutional arrangements/organisational set-up

The States have the constitutional right to plan, implement, operate and maintain and cost recovery of water supply and sanitation projects and municipal corporation, municipality, municipal council, and notified area committee/authority for towns or on a state/regional basis to specialised agencies at the local levels.

The Public Health Engineering Department (PHED) is the principal agency at the State level for planning and implementing water supply and sanitation programs. In several states, statutory Water Supply and Sanitation Boards (WSSBs) have taken over the functions of the PHEDs.

Ministry of Housing and Urban Affairs (MoHUA) formulates policy guidelines concerning the urban water supply and sanitation Sector and provides technical assistance to the States and Urban Local Bodies (ULBs). Central Public Health and Environmental Engineering Organization (CPHEEO) supports MoHUA in policy formulation and also handholds States by providing technical advice. State Water Supply and Drainage Boards (SWSDBs) support ULBs in planning, designing, and implementing sewerage and wastewater treatment infrastructure. 

Ministry of Environment, Forest and Climate Change (MoEFCC) and line agencies play a role in planning, promoting, and coordinating environmental policies and programs in the country and  set environmental standards (especially the discharge standards for treated wastewater). The Central Pollution Control Board (CPCB) was constituted under the Water Act in 1974 as a line agency of MoEFCC with the responsibility to prevent, control, and diminish environmental pollution and to set the wastewater discharge standards for the entire country. At the state level, state pollution control boards (SPCBs) are responsible for the implementation of legislation related to environmental pollution.

The National River Conservation Directorate (NRCD) in the Ministry of Water Resources, River Development and Ganga Rejuvenation (MoWR , RD&GR) is implementing the Centrally Sponsored Schemes of National River Conservation Plan (NRCP) and National Plan for Conservation of Aquatic Ecosystems’ (NPCA) for conservation of rivers, lakes and wetlands in the country.

The pollution reduction works taken up under the NRCD include: interception and diversion works/ laying of sewerage systems to capture raw sewage flowing into the rivers through open drains and diverting them for treatment; setting up of STPs for treating the diverted sewage; construction of low cost sanitation toilets to prevent open defecation on river banks; construction of electric crematoria and improved wood crematoria to conserve the use of wood; river front development works, such as improvement of bathing ghats; and public participation and awareness and capacity building.

The Central Government acts as an intermediary in mobilising external assistance in the water supply and sanitation sector and routes the aid via the State plans. It also provides direct grant assistance to some extent to water supply and sanitation projects in urban areas under the various programs of the Government of India.

Initiatives of the Government of India

• Water (Prevention and Control of Pollution) Act of 1974 (amended 1988 
• Environment (Protection) Act of 1986
• Ganga Action Plan (GAP-I 1985, GAP-II 1993) and National River Conservation Plan 
• National Plan for Conservation of Aquatic Ecosystems’ (NPCA) (2015)
• National Urban Sanitation Policy (2008)
• Other essential flagship national programs launched by the Government of India: Namami Gange program launched in 2015. Under Namami Gange Programme, Government has sanctioned 161 sewage management projects at 245.81 billion INR for creation and rehabilitation of 5501 MLD sewage treatment capacity and laying 5,134 km of sewerage network.

Current technologies and practices in UWM

In India, UWM is performed through on-site systems and off-site systems. An onsite system retains wastewater in the vicinity of the toilet in a pit or tank, and the produced sludge is removed periodically to the faecal sludge/septage treatment system. The off-site system removes wastewater from the vicinity of the toilet for disposal elsewhere through  a sewerage network to transport sewage to a sewage treatment plant (STP).

Challenges in domestic wastewater treatment in India

Institutional challenges

• The Urban Local Bodies (ULBs) in India are responsible for the provision and maintenance of wastewater treatment facilities in their administrative area. However, in many cases, they lack the capacity to plan and implement such projects.
• The existing institutional, policy and legal mechanisms to enforce the management of wastewater are riddled with staff shortages in scientific, technical, and administrative domains that limits the capacity of SPCBs to monitor water quality and disseminate results. 
• Labs are not well equipped due to a shortage of manpower and procurement delays in instruments, equipment, and consumables which leads to delay in water quality testing.  
• Lack of an adequate number of monitoring stations and their geographical spread  limits the real picture related to the extent of water pollution in the country.  Lack of data on water bodies, contaminants or human activities that affect the water quality, lack of health risk assessment studies further limit the monitoring and enforcement capacities of SPCBs. 

Regulatory challenges:

Challenges in relation to regulation occur in standards, monitoring, and jurisdiction. The Pollution Control Boards (PCB) and an active judiciary including the National Green Tribunal (NGT) look after the pollution control.

The major challenges with the standard setting for water pollution include the diversity of pollutants, multiple uses of treated as well as untreated water, the amount of dilution that may happen when the pollution load is released to a neighbouring water body. The existing challenges in the set standards include the differences in the standard setting for different uses. Better defined water quality standards need to be met with rigorous monitoring in order to detect pollution levels, trace them back to the source and estimate their impacts.

Economic challenges

Smaller cities and towns face difficulty in finding necessary resources for setting up STPs due to  high capital expenditure and operation and maintenance costs, which also discourages the entry of private players.  

In contrast with Decentralised Wastewater Treatment (DWWT), centralised systems have higher capital and O&M expenses due to more complex systems, need for technical expertise, and energy requirements. Finding appropriate land for Centralised Wastewater Treatment (CWWT) is difficult considering the higher land values in urban areas. In addition, the phased investment considering the population growth and land-use pattern is difficult in centralised STP systems.

Technological challenges 

An over-dependence on older technologies for handling wastewater due to limited funds and higher expenditures pushes the government to choose technologies with lower capital costs despite their poor performance parameters. The knowledge gap along with the ignorance regarding newer technologies further leads to the perpetuation of outdated and inefficient technologies.

Social challenges 

The citizens are usually not well informed about the issues related to water scarcity and the positive outcomes of water reuse and recycling. In many cases, people are reluctant to use reclaimed water for both potable and non-potable purposes. Recycled water is very less likely to be accepted for drinking purposes compared to its non-potable purposes like irrigation of parks. People often have negative emotions of fear and disgust when it comes to the usage of recycled wastewater

Global innovative, cost-effective and sustainable solutions for UWM 

• Decentralised approach for UWM
• Nature-based Solutions
• Innovative applications for wastewater treatment and reuse
• Reuse of treated wastewater
• Approaches for promotion and adoption of sustainable UWM solutions
• Public private partnerships
• Community participation
• Performance evaluation of treatment plants

Capacity building and raising awareness for UWM 

Capacity building is an essential aspect of Urban Wastewater Management (UWM) and should focus on raising awareness and building capacity for policymakers and planners who deal not only at the city level but also towards local, regional, and national level in managing wastewater. Capacity-building can also help in attracting stakeholder involvement in managing wastewater.

Way forward

The White paper argues that although positive examples of wastewater management exist in the country, these efforts are isolated examples that need to be adapted to suit other contexts.

• Future attempts at bridging the gap between wastewater generation and treatment should focus on sustainable solutions based on  innovations in science and technology and should take into consideration centralised or decentralised infrastructure and devise conventional, advanced or nature-based solutions based on context and keeping in mind a holistic picture of water-land-people and ecosystems.
• Holistic urban wastewater management requires data from all key stakeholders under different  environmental conditions. Regular monitoring of data is the key while utilising wastewater as a resource. Development of affordable data monitoring tools and regular and effective monitoring can greatly help to sensitize stakeholders on extent of wastewater generated, processed and reused.
• There is a need to setup Apex bodies (with participation from Government agencies, academia, industry and public organisations) to manage wastewater treatment systems through extensive collaborations. Updating and applying best management practices for urban wastewater scenarios, with active participation from global communities to avoid technology duplications is crucial in the process. 

The complete report can be accessed here