On the occasion of World Water Day on March 22, it is important to revisit the issue of linking rivers and understand the crucial role this can play in addressing the needs of water-scarce regions.
Appreciating some macro truths about India’s water availability might be in order. The availability of water per person will be only 1445 cu.m per annum in 2050, which is less than 1700 cu,m, the quantity required for livelihood as fixed by the UN, World Bank and analysts. And, this is after taking the entire surface and groundwater available into account, amounting to 238.49 million hectare metres (MHM).
If the utilisable water of the country alone is taken into consideration (108.60 MHM) for a projected population of 1,650 million in 2050, the per capita available water per year comes down to 660 cu.m per annum. Sandra Postel, a renowed water expert, points out in
The inter-basin transfer proposals by the National Water Development Authority envisage utilisation of an additional 20-25 MHM of water resources. According to a very preliminary study, about 16 MHM of water resources can be additionally utilised through artificial recharge, totalling about 41 MHM. In other words, overall availability of water can be enhanced by close to 20 per cent.
In this connection, it is important to note that the storage build-up is rather low. For a population of 1,210 million in 2011, the per capita storage capacity amounts to 350 cu.m, compared with 5961 cu.m in the US and 2,486 cu.m in China.
There are about 45,000 large dams in the world of which 46 per cent are in China, 14 per cent in the US, 9 per cent in India and 6 per cent and 3 per cent, respectively, in Japan and Spain. This is despite the fact that India’s population accounts for 17 per cent of the world’s population.
With over half the population dependent on agriculture, the country’s dependence on land and water is rather high. Hence, the need for large technological interventions cannot be discounted.
(The author is a water technologist.)