03 May 2017 14:04:01 IST

It’s water, stupid!

Water scarcity will get worse in the coming years. For India especially, this is not good news

I’m sure you would all have been told in early childhood that earth, also called the ‘blue planet’, is blessed with enormous water resources — two-thirds of its surface is just water. Have you ever wondered, then, why there is ‘water scarcity’?

Well, a part of the reason is that while water is an abundant resource, very little of it is available in the form fit for ready human consumption. Most of the H 2 O on the planet is salt water — perhaps, evolution, left to itself, will provide an answer, and the homo sapiens of the distant future may be as comfortable with salt water as a shark or a whale. But today, only 2.5 per cent of global water resources are made up of fresh water.

Is that plenty?

Yes it is, but here is another interesting data point. Only one per cent of that 2.5 per cent, or 0.025 per cent of all the water that exists on Earth, is available to us. The rest? Locked deep underground or high up in glaciers and ice.

Well, even 0.025 per cent is not too bad. But all of it is not where we want it and we have to be judicious in using it. It is a precious resource, and it is not to be trifled with.

But we humans have been trifling with it, and without a thought to consequences. It is going to come back and hit us. Those who expect to live on this planet for another five to six decades would do well to know that, unless tackled, a water crisis is looming over the horizon.


For us Indians, it is worse. India is technically a ‘water-stressed’ country. By definition, a country is ‘water-stressed’ if the renewable annual freshwater supplies falls below 1,700 cubic metres per person (’Water scarcity’ is below 1,000 cubic metres, and ‘absolute scarcity’ is below 500 cubic metres).

According to the International Energy Agency, a billion people today live in areas of water stress and this figure is expected to triple by 2025 (just eight more years!). A good guess is that half of them live in India. If we don’t watch it, we are going to slip from ‘water stressed’ to ‘water scarce’.

And do you know why India is such a water guzzler? The answer is one word: coal.

The fossilised culprit

India’s electricity demand is growing at a rate of 6 per cent. Today, our country has 192,163 MW of coal-fired power capacity (our total electricity generating capacity is 326,848 MW).

In 10 years, that is by 2027, this will have grown to 277,000 MW. Today, the coal plants produce 950 billion units. In 2027, they are expected to generate 2 trillion units. Now, each unit of power — or kWhr — generated from coal requires as much as three litres of water, according to the Ministry of Power.

Today, coal-based plants guzzle 2,800 million cubic metres of water per year, or 7,700 million litres a day (MLD -- one cubic metre can hold 1,000 litres of water).

Come 2027, our 277,000 MW of coal power plants will drink up 12,000 MLD of water.

Even today, the country’s thermal power plants are facing difficulties in finding enough water. Water resources are not going to increase, but demand for water will from all claimants — for drinking, agriculture, and so on. If finding 7,700 MLD today is difficult, how easy will it be to find 12,000 MLD, when there is more demand from other uses?

A bizarre solution

The Government of India has come up with a rather bizarre answer. Its idea is to treat sewage water and use the treated water in coal power plants. It estimates that today, the country generates 62,000 MLD of sewage, of which 23,277 MLD is treated.

Why is this bizarre? Here is why, from government’s own words. The following is from a recent Ministry of Power document:

“Based on the water quality data available, it may be necessary to provide a tertiary treatment plant in addition to the secondary treatment being done at STPs, to achieve the required power plant water quality. As such, additional investment may be required by the power plants for the tertiary treatment plant and treated water conveying pipeline from the STP boundary up to the doorstep of power plants. Any such investment, on this account is already made pass-through in the tariff policy and this cost shall be factored into fixed costs so as not to disturb the merit order of such thermal plants. Also, since the quantity of sewage generation varies with the time of the day, the treated sewage water quantity also will vary over the day and, therefore, this may require a storage facility to cater to such fluctuation and maintain a uniform supply round the day on a 24x7 basis. (sic)”

Can you believe it? What the government is suggesting is, take water from our bathrooms and toilets, treat it thrice, create storage facilities and use it in thermal power plants. The cost of it all will be “factored into fixed costs” which means you and I have to pay for it.

This process has already begun. NTPC’s plants at Solapur, Mouda, Meja, Dadri and Patratu use treated sewage water and the government-owned company is in “active negotiations” with municipalities.

Is this the answer?

No. The answer lies in saying ‘no’ to coal. Even treated sewage water has other uses.

The answer is a major push into renewables, coupled with energy efficiency and conservation. Wind power does not need a drop of water; solar needs very little, for cleaning, and even that can be avoided if solar plants take to robotic cleaning that uses brushes instead of water. Hydro projects must be expedited; linking of rivers must happen for better water distribution.

Coal-powered power plants are not only polluting the air we breathe, giving us lung cancer, producing globe-warming carbon dioxide with all the disastrous consequences, but also parching our throats.

Coal is the enemy of mankind. It lies buried — let it remain there.