Water is the very foundation of life on earth and man's quest in space for habitable planets focus mainly on existence of water. Of course air is also an essential prerequisite for any life to survive and unlike water it is available in plenty in this planet though its quality is questionable in many places adversely affected by uncontrolled pollution caused by man himself. As for water there is no dearth of it as more than 71% of earth's surface area is covered by water. Out of this 96.5 % is found in sea and oceans unfit for use for any human activity. !.7% ground water and another 1.7% in glaciers and ice caps in Antarctica and Greenland are considered pure. However for all practical purpose only 2.5 % of water on earth is considered fresh water fit for human use while 0.3% of earth's fresh water supply comes from lakes and rivers. These figures clearly indicate that water is not an inexhaustible resource and therefore must be conserved as much as possible, avoiding wastage with all the means available to man.
Human body is made of water to the extent of 60-78% depending on the body size and for sustenance body water needs to be replenished at the rate of 1 ml per calorie consumed through the food. On an average a man needs about 3.7 liter water per day taken directly as well as through the food while the corresponding figure for a woman is fixed at 2.7 liters a day. Drinking water or potable water has to conform to certain minimum standards and nature's water has to be cleaned up to remove undesirable and unsafe components, suspended as well as dissolved for which many technologies are available. In acute water scarce countries huge plants are able to convert sea water with 3.5% salt content into potable water with minimum cost. According to estimates by some international agencies more than 50% of the world's population will face water crisis. Even to day it is presumed that almost 1 billion people lack access to safe water while more than 2.5 billion lack access to sanitation due to water scarcity. Imagine the tragedy that is unfolding to day when about 1.4 million children die due to severe diarrhea because of consumption of contaminated water!
In most developing countries about 90% of fresh water exploited is used by the agriculture sector and there is a fierce competition between potable water sector and irrigation sector for tapping the available water supply. In contrast a developed country like the US uses only 30% of its water resources for agriculture through deployment of modern cultivation and water conservation technologies. However in India, of the 700 billion cubic meters (BCM) of water consumed annually 88% goes for irrigation while the industry accounts for 8%. According to projections for future India is likely to tap about 833 BCM water by the year 2025 from all sources out of which 81% will go for irrigation while 11% will have to be supplied to the industrial sector. The industrial need will go further up demanding more than 18% of the water available. Household needs which stands at a mere 5% to day may go up to 11.% of the total fresh water available. Thus there is a clashing scenario for water among farmers for irrigation, industry and the house holds for daily use and unless agricultural technologies are upgraded to use less water without harming the productivity expectations, India will be in a dire straight in a few years from now!
It is interesting to see that our thermal power power plants gulp more than 70% of the industrial water which will further increase if the present government's thrust for more power plants, especially nuclear plants materializes after recent agreements with the US government for collaboration in the nuclear energy sector. Industry wise Steel industry consumes about 7-10 cubic meters (CM) of water for every ton of steel produced, paper industry needs 75-100 (CM) per ton of paper produced, power industry's need is 75-100 (CM) per megawatt hour generated while soft drinks industry consumes 3-5 (CM) per cubic meter of products made. As electricity production in the country is massive, total power needs by the power sector become huge while other sectors do not produce even a fraction of the end product output by the power industry, hence their apparently smaller share in the industrial water use..
Generally food processing industry needs huge volumes of water and especially soft drink sector depends heavily on water as its products viz beverages contain almost 100% water by volume. Similarly others like fruit and vegetable canning, bakery industry, dairy sector, breweries and distilleries, sugar factories, poultry farms etc all require water to maintain peak hygiene and sanitation, letting out in the process large volumes of spent water. Pollution from food and beverage industry is considered vey high and in spite of tight fisted laws existing in the statute book most of them go scot free because of lax enforcement by the pollution control agencies working at the state level. If the new government's "make in India' mantra becomes the national strategy, the industrial sector will need much more water than that is predicted.
Conflict between the industry and people for water access may intensify and the recent controversy in Gujarat regarding diversion of water from Narmada meant for irrigation to a giant soft drink manufacturer is still fresh in our minds. Similar incidences of diversion of water intended for irrigation being diverted for sugar and distilleries in Maharashtra are just a preview of such mega conflicts in future. We may recall the shameful incidence in Plachimeda in Kerala where a soft drink giant set up a plant in the beginning of 2000 which had to be abandoned due to local uprising by people because of supposed over exploitation of ground water and alleged pollution of ground water by the effluents let out by the factory into surrounding fields. India is in a Catch 22 situation with such a dilemma faced by the nation to meet the expectations of one and all vis-a-vis water and government must address this problem sooner than later to prevent discontent among its citizens in the coming years.
A national policy on agriculture can draw the necessary road map for water sparing crops and developing varieties that can be grown with sea water. Enormous wastage of water happens through the chain of activity of human beings in their every day life and sooner this tendency is curbed better it will be for the country. The agricultural sector presents a paradoxical picture where a section of farming community gets high share of water while another section has to eke out a dreary existence using drought based agriculture! Water intensive crops like sugarcane and paddy must be taken up to the minimum extent possible while development of varieties that need significantly less water must be a priority for the scientists in ICAR and agri varsities. Similarly it is time a national water policy is evolved to "optimize" use of water, conserve water resources without running the danger of over exploitation, launch intensive waste recycling efforts and massive sea water reclamation as the country has a long coastal area with easy accessibility. A country like Israel which is a willing collaborator of India can teach us lot of lessons in increasing water supply from our precious resources and its optimal use.