Water productivity of irrigated agriculture in India: potential areas for improvement

The objective of the study is to explore the scope for water productivity enhancement in irrigated agriculture in India through: i] water control; ii] optimizing nutrient input to crop; iii] improving the quality and reliability of irrigation water; and, iv] growing crops in regions where climate is favourable. The study is based on data from three important river basins in India, viz., Indus, Narmada and Sabarmati. The study involved: 1] estimating the incremental water productivity of selected crops viz., wheat and cotton in response to applied water, and fertilizer dosage; 2] estimating water productivity of the same crop across agro-ecological zones within the basin, and 3] comparing determinants of crop water productivity with different sources of irrigation with differential reliability and quality. Most farmers are applying water within a regime where the yield response to both irrigation and fertilizer dosage is positive. Also, their water application corresponds to a regime where water productivity (Rs./m3 ) response to irrigation is negative and fertilizer is positive. But, in certain situations, farmers’ water application regime corresponds to a regime where both yield and water productivity responses to irrigation are either positive or negative. Within basins, for the same crop, water productivity in both physical and economic terms is much higher in high rainfall, sub-humid area as compared to that in low rainfall, arid areas. The quality and reliability of irrigation can significantly impact the type of crops chosen by farmers and the crop yield, thereby raising water productivity. There is ample scope for improving water productivity in irrigated agriculture through water control. But, in most cases, it may lead to reduced net return per unit of land. Hence, they would have incentive to go for water control measures only if there is sufficient land, which can be put to use for irrigated production using the saved water