Expansion of irrigation is normally viewed - and rightly so - as a reliable means of drought-proofing an area. But it is not a complete solution. For, even after harnessing all available resources of water, nearly 40 per cent of the country's total area will remain critically rain-dependent. Promotion of rainwater harvesting and its preservation are thus indispensable. Preferably, one-third of rainfall received during a year should be stored in surface water bodies like ponds, tanks and dug wells for immediate use and the remaining should be guided to sub-surface layers to replenish groundwater. Underground storage is by far the best method to preserve water, especially in hot and arid zones where evaporation from surface water bodies is high. At present, the bulk of annual rainfall is allowed to run off, eroding precious soil in its wake. Only a small part percolates down to the subsurface aquifers.
A very apt slogan was coined in Hindi some years ago for on-the-spot rainwater preservation. It said: "khet ka pani khet mein, gaon ka pani gaon mein" - meaning water falling in a farm should be retained in the farm itself, and that falling in a village, in the village itself. Though watershed development approaches, too, seek to hold water within a specific watershed - a contiguous area that drains into a common depression - they are distinctly different from the idea of retaining water in the fields and villages. The latter seems more practical because it allows greater individual control over the storage and utilisation of preserved water. A watershed, on the other hand, usually cuts across several villages and requires a large number of residents and agencies to cooperate - a difficult ask. It is, thus, time to appreciate the value of water conservation in coping with recurring droughts.