The Supreme Court has delivered its verdict on the sharing of Cauvery water by Karnataka and Tamil Nadu. Tamil Nadu’s share has been reduced and this has caused great disappointment. While Tamil Nadu and Karnataka continue their conversation on sharing of Cauvery water, it would be useful to take advantage of the important recommendation made by the Supreme Court for establishing a Cauvery management board speedily. This board should include eminent water technologists and agriculture specialists. In my view, such a management board can help to ensure greater economy and equity in sharing Cauvery water by stimulating attention to the following:
n Demand management all the Cauvery basin states should reduce the demand for water by introducing cropping patterns requiring less water and by adopting drip irrigation and other water saving techniques. The less water requiring cropping system should pay attention to crops which are in demand in the market and which can enhance the income of farmers per unit of water.
n Supply augmentation the Supreme Court has pointed out that there is scope for Tamil Nadu benefitting from its underutilised aquifer. One method of augmentation is mandatory rainwater harvesting. Since Tamil Nadu is a rain shadow region and water becomes available largely during the Northeast monsoon period, there is scope for water harvesting and storage.
The Cauvery management board can give urgent consideration to various opportunities for both demand management and supply augmentation, so that the reduced water allocation does not affect the productivity and income security of the numerous small farm of Tamil Nadu. Tamil Nadu could set-up a water security board inorder to ensure maximum benefits from the Cauvery management board proposed by the Supreme Court.
Water security has to be built not only in quantitative dimension but also qualitatively. For this purpose, we need interaction among technology, public policy and people’s participation. In the area of technology, there is already much progress in rainwater harvesting and solar energy desalination. There are new approaches like system of rice intensification (SRI) that can help to reduce water requirements by increasing yield per litre of water.
In the area of integrating water with nutrients, there is much scope for introducing new methods like the application of neem coated urea. Neem coated urea becomes a slow release fertiliser and reduces the greenhouse gas emission. Further neem is also a botanical pesticide and can help to control pests. Once there is irrigation water security, the cultivation of high yielding varieties becomes possible. An urgent task today in India is improving productivity per unit of land. This is possible through the choice of new varieties and also new methods of feeding the plant. Both breeding for high yield and feeding for high yield should become part of the agronomic technology.
Tamil Nadu farmers are already familiar with irrigation, techniques which can optimise the use of water. In fact one of the earliest irrigation system in the world was the Grand Anicut (Kallanai dam) constructed by the Chola King Karikalan. There is much to learn also from the tank method of conservation of water. There is a proverb in Tamil which says, “Every village should have a temple, and every temple should have a tank”. Temple tanks have often come to the rescue of the local population in years of severe drought. This was probably one of the earliest water harvesting and storage systems.
The spiritual value of tanks in addition to their practical value will be clear from the various well known religious functions being associated with them. Mahamaham is celebrated (festival celebrated every 12 years) in one of the temples in Kumbakonam, is one of the examples. Similar festivals are also organised in association with tanks in several parts of the country. It will be possible for us to built sustainable water security system if we are able to integrate traditional wisdom with modern technology.
Our prime minister has been placing considerable emphasis on the augmentation of irrigation facilities and water harvesting. The World Water Week is held in August every year in Stockholm, Sweden, where one of our eminent water harvesting experts, Rajendra Singh, will be honoured with the prestigious Stockholm Water Prize. I have personally seen the work of Rajendra Singh in Rajasthan where he has tried to motivate local communities in saving all the rain water and using it economically and effectively. I hope this global recognition to one of our water security experts will stimulate state governments to make rainwater harvesting mandatory both in farms and homes. This will help to strengthen very considerably our water and food security system.
Another aspect which needs attention is the working together of the World Water Partnership and the World Soil Partnership, which was established by FAO a few years ago on my suggestion. Land use decisions are also water use decisions and hence the management of land and water should be handled in a symbiotic manner. We will then be able to ensure sustainable water and food security.
(The writer is an agricultural scientist who led India’s Green Revolution )