Even Waste Water Shouldn't Be Wasted

On March 22, we will celebrate the 24th World Water Day. The theme this year is 'Waste Water'. This day is generally observed to spread awareness among the general public and focus on its importance in sustainable development.

In any discourse about water, waste water is less talked about as against normal water supply. But waste water is a resource in a circular economy, and its safe management is an efficient investment in human health and the ecosystem. Although waste water is water that's generally wasted, in reality it is a resource.

Uses and abuses

The sources of waste water are many: domestic, industrial, commercial, agricultural, surface run-off or storm water, and sewer inflow. Waste water, once treated, can be recycled and/or reused for drinking purposes, in industry, in the artificial recharge of aquifers, in agriculture, in the rehabilitation of natural ecosystems and so on.

Untreated waste water is contaminated with pollutants. Such water when used for agricultural crops, is often polluted with urban waste containing not only a mix of chemical and biological pollutants, but also high levels of pathogens from excreta. This generally impacts human health. Therefore, in this case, waste water should be treated, or WHO guidelines should be followed for restricted use of 'untreated water'. For example, these guidelines prescribe discontinuation of irrigation with untreated waste water for a few days before harvesting of crops in order to allow pathogens to die in sunlight.

Globally, 10 per cent of waste water is treated. About 69 per cent of India's water is untreated and 39 per cent of actual operating capacity does not meet the regulatory standards (CPCB 2009). Waste water is discharged directly into water bodies, overloaded rivers, lakes and the ground with toxic chemicals and wastes. This consequently poisons water resources and supplies. These toxins feed their way into plants and animals, causing severe ecological toxicity at various levels, including in the human food chain.

Development strategies

The river Ganga, for example, receives, in its journey, roughly 500 million litres per day (MLD) of partly treated or untreated industrial effluents from over 700 grossly polluting industries, and about 3,000 MLD waste water from urban bodies, thus exerting a huge organic load. Unless the waste water is treated and discharged, our rivers, like the Ganga, will continue to be conveyors of contaminants, quite contrary to the public perception or aspiration of their being pristine, life giving streams.

India's strategy for its new path of development also focuses sharply on the development of smart cities as drivers of GDP growth. Crucial to the growth of smart cities is the recycling of waste water.

Such recycling is happening in some of our proposed smart cities such as Bengaluru, where tertiary treatment of waste water enables the utility to supply water to airports, parks, industries, and construction sites at suitable user fees. One of the best international examples in urban water recycling is Yokohama in Japan. More than 99 per cent of Yokohama’s population is connected to sewers; it's treated waste water is precious, and is being supplied to various locations of the city. Indian smart cities could take a lead from the Yokohama example for maximising their waste water management. Given the finiteness of fresh water supplies, the growing demand of fresh water, and depleting groundwater levels, the recycling and reuse of waste water opens up big business opportunities. Estimates vary on the size of business opportunities in India's water sector. An estimate (Kotak Institutional Equities, 2012) puts the annual figure at $30 billion, of which waste water is emerging as a thrust area. With about 26 billion litres of water going untreated daily, the investment opportunities in this segment are estimated to be in the range of $400 million, assuming a four-year completion cycle of the operating system.

However, the waste water treatment market is unorganised, and a sizeable portion is dominated by small and medium-sized domestic players. This market is mainly dominated by municipal segments. The enforcement of regulatory standards for waste water from industries and municipalities is expected to enhance the size of the waste water market. Markets for waste water treatment are expected to grow in value and volume.

Policy support

In India, there is policy support for recycling and reuse of waste water. For example, the National Water Policy 2012 recognises that "recycle and reuse of water should be the general norm". Many countries have implemented similar policies in right earnest. For example, in Israel, 86 per cent of urban waste water, after suitable treatment, is reused in the agriculture sector.

The available water supply is finite, and its spatial and temporal variations are well known. By 2050, it is estimated, India will be water-scarce in terms of per capita availability of water per year.

India's demand for water is growing in all sectors, given continuing economic growth and improving lifestyles. Climate change, due to human induced interventions, will affect the variability of water supply in many countries, including India. The National Water Mission of India has targeted improving efficiency by 20 per cent in all sectors. This is difficult to achieve unless water is conserved, recycled and reused.

Constitutionally, water is a state subject in India, and the Centre comes into the picture only when there is regulation of inter-State river waters. The recycling and reuse of water thus comes into the States' and local bodies' domain. The governments, at the Centre as well as in the States, should give incentives to various players in this regard. The regulatory norms for maintenance of waste water standards should be strictly enforced. A combination of these instruments will enhance the progress of recycling and reuse of waste water, which is crucial to India's development.