Water-stressed India: Channel treated wastewater from cities to irrigation and industry

Treating wastewater and utilising it in agriculture and industry can protect freshwater and groundwater resources from overexploitation and pollution. (Representative image)

Bengaluru, one of India's largest and fastest-growing cities, has been facing a severe water crisis for many years. The city’s rapid urbanisation, coupled with inadequate planning and infrastructure, has led to a severe shortage of drinking water. As a result, the city is heavily dependent on groundwater, which is rapidly depleting due to over-extraction.

Meanwhile, Bengaluru generates around 1,440 million litres of wastewater every day, but only a small fraction of it is reused. Most of the wastewater is discharged into lakes and rivers, polluting them and further exacerbating the water crisis. The situation in Bengaluru mirrors what could be the situation in many other Indian cities, and highlights the urgent need to adopt sustainable water management practices across the country.

The Wastewater Problem

India is ranked the 13^th most water stressed country globally. Most of India’s population (18 percent of world population) live in water-stressed areas and depend on the monsoon to meet its water demand. In 2020, the Central Groundwater Board of India reported in the National Compilation on Dynamic Groundwater Resources of India that 16 percent of assessment units (blocks/ mandals/ firkas/ taluks) were overexploited, while 4 percent of them were critical and 15 percent at semi-critical stage.

In terms of wastewater generation, India tops the chart amongst the South Asian countries. According to a recent assessment by the Central Pollution Control Board (CPCB) in 2020-21, about 72,368 million litres per day (MLD) of sewage is generated, out of which only 20,236 MLD (28%) is effectively treated. The rest 72 percent of wastewater finds its way to lakes, rivers, open drains and groundwater that leads to contamination of resources.

Utilising Wastewater 

There is a growing demand for alternative sources of water which is being driven by factors like depletion of freshwater resources and the need to conserve them. With the goal of promoting treated water reuse as a sustainable solution to water scarcity, the National Framework for Safe Reuse of Treated Water (SRTW) was launched by the Ministry of Jal Shakti (MoJS) in 2020, and an updated version came out in 2022.

Treated water is called “Apna Jal – Our Water” and the framework provides guidance and recommendations for its reuse in sectors such as agriculture, industry, construction, aquifer recharge and municipal uses. Treated water has the potential to be reused for various non-potable purposes and has several benefits.

A September 2022 whitepaper by NITI Aayog and Atal Innovation Mission noted that the use of treated water in agriculture can increase crop yield by supplying essential nutrients and reduce fertilizer dependency by 40 percent. A study by the International Water Management Institute reports that collection and adequate treatment of 80 percent of urban wastewater could satisfy 75 percent of the industrial water demand.

Nudging Local Governments

Countries such as Israel have made it mandatory to supply treated water for irrigation in farmlands. However, many developing countries like India, are still at a nascent stage to accept and adopt nationwide reuse of treated water. The state governments of Chhattisgarh, Haryana, Jharkhand, Madhya Pradesh, Punjab, West Bengal, Karnataka and Gujarat, and the Union Territory of Jammu and Kashmir have launched policies for reuse of treated wastewater. Policies are in the draft stage in Maharashtra, Tamil Nadu and Uttar Pradesh.

The states, through their policies, have set mandatory targets for reuse of treated water. The most ambitious target has been set by Gujarat of achieving 100 percent reuse by 2030. Many state governments/urban local bodies (ULBs) in India are now investing in wastewater treatment plants with financial and technical support from central government to develop and improve their wastewater treatment facilities.

Despite the benefits, adoption of treated water reuse in India has been relatively slow. Lack of infrastructure, inadequate treatment facilities, lack of awareness about the benefits and inadequate synchronisation between institutions and regulatory structures are to blame.

Role For ULBs, Pvt Sector

To overcome the challenges of synchronisation, the National Framework on SRTW has identified and specified the role and responsibilities of different agencies at national and State level. The national level agencies would be responsible for ensuring regulatory standards, providing technical guidance, overseeing performance targets, application of incentives and sanctions, awareness raising and capacity building. While the State -level agencies would support the regulatory framework, ULBs and Panchayati Raj Institutions will lead the on-ground implementation.

A multi-stakeholder approach involving government agencies, industry, academia, and local communities to promote the adoption of treated water reuse is essential. Advanced wastewater treatment technologies can improve the quality of treated water and at the same time reduce capital and operational cost of the wastewater treatment, making the use of treated water more sustainable and affordable.

There is a need for a dedicated policy for reuse of treated water with clear targets, regulations, and guidelines at national level. Lucrative business models to promote treated water reuse projects and inclusion of financial and non-financial incentives for use of treated water can fast track India’s journey towards water security.

Nimisha Singh is Research Associate, and Khalil Ullah Khan is Associate Fellow at The Energy and Resources Institute, New Delhi. Views are personal and do not represent the stand of this publication.