The food grain demand in India would rise to 494 million tonnes by 2050 from the present 247 mt, but our net cultivated area will grow only from 143 million hectares to 145 million ha, a woefully small increment of 2 million ha in the same period. There is no more land that can be converted for cropping. Nevertheless, what is important is the projected area under irrigation that is required to produce enough food demand in 2050; and that is 146 m ha. It means that the irrigated area should grow from the present 79 million hectare by 85% to 146 m ha.
To bring more land under irrigation, we need more water. But water availability is not growing at all. We have a large amount of rain-fed agriculture where the farmer typically just depends on monsoon rains.
Currently, water losses in agriculture take various forms such as surface run off of rain water, evaporation losses at the time of conveyance of water or flood irrigation, percolation losses in canals or farms, depletion of underground aquifers, etc.
There is a wide range of technological solutions that can not only help us improve the savings, but actually generate water or create water. With the current methods of irrigation practised throughout our country we waste 70% of irrigation water; implying that water efficiency in agriculture is only 30%. Every time a farmer irrigates an acre of sugarcane, he pours approximately 2,50,000 litres of water. The crop uses (at its mature stage) only 30% of this volume. The rest goes away from the source into a non- recoverable phase.
If we intervene with technology and restrict the application rate and time and make water available to the sugarcane crop as per its requirement, we not only reduce the water used for growing the sugarcane; we also avoid the periodical dips and highs in soil water status, a reason for lower yields and inferior quality of produce.
On an average, an acre of sugarcane, when irrigated with drip technology, will ‘generate’ surplus water for another acre of land with the same crop. So the farmer can double the area under irrigation using his existing water source. Water productivity increases; we say we increase water security along with food security. This is just an example of one crop. Similarly, micro irrigation can be applied to almost all crops.
Traditionally, canal command irrigation results in excessive water use, soil degradation and results into lower productivity, still lower irrigation efficiency without proper recovery of water charges and over 20% per year cost of maintenance. All these results in unviable investments as upstream farmers get more water. This also results in unviable and inequitable water distribution.
The writer is the managing director of Jalgaon-based drip irrigation major, Jain Irrigation Systems