Water is indispensable to life on Earth, and its scarcity is a global concern. This scarcity can decrease food security and reduce access to water for industrial and domestic purposes. It also has broader economic, humanitarian, and ecological implications.
According to the Organisation for Economic Co-operation and Development, irrigation in agriculture accounts for 70% of water use worldwide. Intensive groundwater pumping for irrigation depletes groundwater resources and has negative environmental consequences, causing a significant economic impact on the agricultural sector and beyond.
In India, too, the majority of water consumption is for irrigation in agriculture, as per the Central Ground Water Board.
Source: Dynamic Ground Water Resource of India by Central Ground Water Board
1. It is therefore concerning that India is facing an increase in water scarcity. Northern India, particularly, experiences significant groundwater depletion. While the nation's average Groundwater Extraction was 60.08% in 2022, an improvement from 63.33% in 2017, Haryana, Punjab, and Rajasthan bucked the trend, exceeding the groundwater extraction by 100% in 2022.
The Green Revolution of 1960, marked by the adoption of water-intensive high-yield seed varieties, boosted agricultural production from 55 million tons at the time of independence to 260 million tons of food grains today, but strained water resources. In Punjab and Haryana, the epicentre of this revolution, groundwater depletion surpasses natural replenishment rates by 65%, and 34%, respectively. Free/ heavily subsidised electricity to run pumps, and no cost for water initiated to support the Green Revolution, led to excessive irrigation, exacerbating the depletion of groundwater.
Although mandated by Section 55 of The Indian Electricity Act, 2003, nationwide electricity metering remains largely unimplemented due to resistance from farmers' unions, making farmers lackadaisical about their usage. Free water and power are so politically popular in the economies of farm states that leaders do not suggest a change for fear of not being elected to power.
Source: Ministry of Jal Shakti
2. Let's look at water consumption numbers by various crops in India and analyse further why certain states are experiencing groundwater depletion.
Rice, a staple food globally and in India, demands 3000 – 5000 litres of water per kilogram for production. India, the second largest producer and consumer of rice, also emerged as the largest exporter in 2023, accounting for 40% of global rice exports.
Source: Agricultural Statistics at a Glance 2022
The above graph shows that Punjab's per-hectare rice production surpasses West Bengal's by 43.33%, despite Punjab cultivating only around 76% of West Bengal's total rice production. This difference is why West Bengal, despite being the largest producer of this water-intensive crop, hasn't depleted its water resources at the same alarming rate as Punjab has.
While wheat cultivation is less water-intensive compared to rice, it still requires 900 - 1000 litres of water per kilogram of production. However, because of its importance as a staple food in India, it still consumes a significant amount of water during cultivation.
Punjab and Haryana produce around 43% and 30% of the total wheat yield of Uttar Pradesh, the largest producer. However, their per-hectare rates exceed that of Uttar Pradesh by approximately 16% and 25% respectively. This further shows the impact of the Green Revolution, and consequently, the over-exploitation of groundwater resources in the North-Western states of Punjab and Haryana.
Sugarcane, a crucial cash crop, requires 1500 – 3000 litres of water for 1 kg of its produce. Used in diverse industries like sugar, biofuel, paper and pulp, it also contributes substantially to economies worldwide. Globally, India ranks second in both sugarcane and sugar production, but leads as the highest consumer of sugar, consequently dominating the global sugarcane and sugar market.
Tamil Nadu and Karnataka produce only 8.73% & 35% of what Uttar Pradesh produces. However, the per hectare rate of production of Tamil Nadu and Karnataka is much higher than that of Uttar Pradesh, the largest producer by almost 26% and 17% respectively. This explains why both these states have been coloured red (refer figure 2), with a 70% extraction of their groundwater resources.
Uttar Pradesh holds a significant position in the production of all these three crops: it's the second-largest producer of rice, and the largest producer of wheat and sugarcane in India. Despite having lower per-hectare production rates compared to other states, the sheer volume of these water-intensive crops cultivated in Uttar Pradesh might have contributed notably to the depletion of its water tables, resulting in an overall extraction rate of 70%.
3. The World Bank has helped the state government of Punjab pilot an innovative scheme to save electricity and conserve groundwater, namely “Paani Bachao, Paisa Kamao”. The scheme incentivises farmers to reduce groundwater usage. According to the World Bank, around 300 farmers were enrolled and given cash incentives to save electricity used for irrigation, resulting in water savings of between 6 and 25 percent without any adverse effect on the yield.
But to address water-related issues at a large scale, it is imperative to embrace alternative farming methods, particularly organic farming. Techniques such as Saturated Soil Culture (SSC), Alternate Wetting and Drying (AWD), and System of Rice Intensification (SRI) offer viable alternatives to rice cultivation.
In AWD, irrigation is delayed until a certain period after ponded water disappears, unlike in traditional methods, where it is done immediately. Water table in the field is monitored using a simple perforated field water tube. When the water level is 15 cm below the surface of the soil, it is again flooded to a depth of around 5 cm. The water in the rice field needs to be kept at 5 cm depth to avoid any water stress that would result in severe loss in rice grain yield.
The International Rice Research Institute (IRRI) reports that AWD has enabled Bangladeshi farmers to reduce rice water requirements by up to 30%, while also conserving diesel and electricity for water pumps, and increasing Boro rice yields by 500 kg per hectare. Further, practices such as mulching, tilling, and crop rotation can aid in preserving soil nutrients and conserving water, particularly in sugarcane and wheat cultivation.
Kshitij Sarawgi and Bushra Ansari both work at ISDM DataSights, supported by Capgemini.
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