Newspapers are full of articles on how we are going to have severe water shortages and permanent near-famine conditions for a third of humanity, and how there are going to be major conflicts on the issue. Since the water scenario in the Indian context is something more of our readers will connect with, let’s take an unprejudiced look at our available water resources and their use.
India is blessed with a relatively better situation of water availability compared with many other countries, but it is also much worse than so many others. We have frittered away this advantage over the past decades by mismanaging this invaluable resource. To put it in perspective, India’s annual precipitation is 4,000 cubic km, or billion cubic metres (bcm). Obviously, we cannot put all this water to use because some of it gets evaporated and some is utilized by green cover for sustenance through a process called transpiration. The water available to us for utilization is the part that flows into our river systems or collects in lakes and ponds and what percolates into the ground, where it is stored as groundwater. It has been estimated that out of 4,000 bcm, only about 1,869 bcm is available. However, we cannot utilize this entire water because a major part of it flows in rivers in the areas where there is no use for it or it comes at a time when we are unable to make use of it—for example, during the three monsoon months—and the water simply flows unutilized into the sea. Thus usable water is estimated to be only about two-thirds of this, or 1,123 bcm.
This water would have been quite sufficient to meet the requirements of our population if we could manage it properly and effectively. In 1950 or so, when our population was about 350 million, this available water worked out to more than 5,100 cubic metres for each person a year, while a person needs only about a third of this for a comfortable living. Today our population has risen more than threefold and we have come to a situation where we are just about at sustenance level of water availability.
However, since the availability of water has a huge spatial and temporal variation, there are huge shortages in some parts of the country and excess in some others. The obvious and logical answer to this scenario would be to collect this water when and where it is available and use it when and where required. There are two ways we can store rainwater during the three monsoon months and use it during the rest of the nine months—in lakes and reservoirs or in underground aquifers. Since we were endowed with plentiful water resources at that time, no serious effort was made in the 1950s to conserve water resources.
However, in the 1960s and 1970s, realization dawned and we built many storage dams. But the momentum fizzled out by mid-1980s, with anti-dam lobbies springing up to ape the Western developed world and by the 1990s and the turn of the century, the infrastructure development activity tapered down. Today you can count on the fingers of one hand the number of storage projects under construction and these too are those that were taken up many years ago. Hardly any new storage dams are being taken up today. We have a potential of creating storage for about 410 bcm, but after more than 50 years of trying to develop our infrastructure, we have been able to build storage for only about 225 bcm.
The other way of conserving the available water is to assist the water to percolate into the ground. Under normal circumstances some water does go underground, but with our increasing population and indiscriminate exploitation of the groundwater, the natural process is not self-sustaining and groundwater levels are falling alarmingly in 80-85% of critical areas of the country.
So what does this picture tell us? If our population was not exploding exponentially as it did in earlier years, we would still have a respectable per capita availability. If we had built storage facilities, we could have been storing the rainfall and snow-melt, and utilized it during the dry months. If we had paid more attention to water percolation measures for recharging groundwater more effectively, our groundwater reserves would not be depleting so alarmingly.
So it is mostly our own mismanagement that is responsible for the dire straits that we are in today and unless we gear up to improve how we utilize this precious resource that nature has bestowed on us, we are heading for trouble.
A.K. Bajaj is former chairman of Central Water Commission.