Does micro irrigation increase demand for groundwater?
India is rapidly hurtling towards a water crisis and this is predicted to pose a severe threat to drinking water, agriculture and food security in the country. While a large proportion of water is needed to fulfil agricultural needs, micro-irrigation (MI) has been encouraged in the country to help farmers produce more by using less water and prevent wastage of water.
The Government of India has been promoting micro-irrigation with subsidies, under the Pradhan Mantri Krishi Sinchayee Yojana (Prime Minister’s Agricultural Irrigation Scheme) with a focus on “Per Drop More Crop” and “Har Khet Ko Pani” (water for every farmland).
Micro-irrigation technology has been known to help farmers produce more from less inputs, but some experiences from the ground show that MI technology, while enhancing private benefits, might not conserve water and could even accelerate the depletion of groundwater resources through the phenomenon of Jevons paradox or the rebound effect and lead to an increase in groundwater demand.
However, there continues to be a lack of data to support this theory in India. This study titled Micro-irrigation adoption and the Jevons’ Paradox: A study from four states of India’ authored by Gurpreet Singh, Vasant P. Gandhi and Dinesh Jain published in Agricultural Water Management explored the impact of micro-irrigation in agriculture and the incidence of the Jevons paradox or rebound effect from four states of India, namely Uttar Pradesh, Madhya Pradesh, Telangana, and Maharashtra, which have implemented MI, by talking to farmers from the states.
The study found that:
Total hours of pumping per hectare reduced
There was a significant decrease in the total hours of pumping per hectare after the adoption of microirrigation for all crops by 32 percent per hectare. The highest decrease in hours of irrigation was observed in cotton (52 percent), followed by wheat (41 percent), and banana and sugarcane (39 percent).
Specific crops showed an increase in hours of pumping
Chickpea, ginger, soybean, and beans showed an increase in absolute hours of pumping after the adoption of microirrigation. This increase was highest for chickpea at 55 percent, followed by bottle gourd (27 percent) and ginger (20.9 percent).
Farmers increased their cultivation area after adopting microirrigation
Over 65 percent of farmers across all states expanded their operated area post MI adoption. The highest increases were seen in Madhya Pradesh (98 percent), followed by Maharashtra (90 percent), Telangana (82 percent), and Uttar Pradesh (68 percent). Farmers shifted towards diverse and lucrative horticultural and vegetable crops, increased the area under irrigated pulses, and reduced acreage under cereals and cotton.
Thus technology reduced the hours of pumping for irrigation and thus the per-unit area water consumption. However, with an increase in area, there was an absolute increase in pumping hours by farmers in some crops such as chickpea, ginger, soybean, watermelon, beans, and bottle gourd.
Farmers tried to maximise benefits by using saved water
Thus while microirrigation enhanced water use efficiency across a broad spectrum of crops, farmers increased groundwater extraction (measured by irrigation hours) through increasing area under cultivation, including water-intensive crops and changing their cropping patterns.
The impact of micro-irrigation adoption on water use and conservation thus hinges on the choice of allocation of the saved water by farmers—whether it is conserved or directed towards expanding cultivated areas, transitioning to more water-intensive crops, selling the conserved water, or additional non-farm activities such as animal husbandry.
The study argues that a holistic approach that involves robust institutional measures, a paradigm shift in policy, and a better understanding of farmers’ behaviour is needed for of MI adoption in addressing water challenges in agriculture to be successful. The technology, while fulfilling two key mandates of the Pradhan Mantri Krishi Sinchayee Yojana namely, “per drop more crop” and “Har Khet Ko Pani” (water for every farmland), seems to increase the risk of future consumptive uses.
The way forward
The paper argues that there is a need for a more comprehensive basin-scale investigation of farmers’ behavioural responses to the adoption of micro-irrigation and the subsequent changes in volumetric consumptive water use. It is also crucial to develop market strategies that encourage the cultivation of low water-intensive, high-return crops like fruits and vegetables to improve the household welfare and economic status of farmers.