India draws 80% of its irrigation water from groundwater.
Dr. Nitish Priyadarshi
Professor, Department of Geology
More than two billion people worldwide live in regions facing water scarcity and in India this is a particularly acute crisis. Millions of Indians currently lack access to clean drinking water, and the situation is only getting worse. India’s demand for water is growing at an alarming rate. India currently has the world’s second largest population, which is expected to overtake China’s by 2050 when it reaches a staggering 1.6 billion, putting increase strain on water resources as the number of people grows. A rapidly growing economy and a large agricultural sector stretch India’s supply of water even thinner.
Climate change is one of many forces contributing to an unfolding water crisis. In the coming years, the demand for water will increase as food production grows, populations grow and move, industries develop and consumption increases. This can lead to water stress, as increasing demand and use of water strain available supplies.
Water scarcity is one of the greatest challenges of the twenty-first century. Agriculture, encompassing crops, livestock, fisheries, aquaculture and forestry, is both a cause and a victim of water scarcity. It accounts for the bulk of global water withdrawals. With rising temperatures intensifying demand, in combination with more frequent and severe weather extremes impacting production, the need to address water scarcity in agriculture is apparent. Water withdrawals increased at almost twice the rate of the population in the twentieth century, and a 50 percent surge in food demand is expected by 2050. These matters most severely affect water-scarce regions, as well as areas where a lack of infrastructure or capacity prevents sufficient access to water. It is clear that there is an urgent need to address water scarcity.
Food and water are connected. Have you ever looked at a plate of food and wondered, “How much water it takes to make it?” The world is facing a water crisis. It is estimated that over2 billion people are affected by water shortages in over 40 countries, and the extensive withdrawal of water for agriculture from river, lakes and aquifers results in limited supplies for other human needs, such as drinking, washing, cooking and sanitation. According to the UN World Water Development Report, the average supply of water per person will drop by a third in the next two decades. Agriculture is by far the biggest user of water. Because of this, the water that a person ‘eats’ everyday contained in food products is much larger than the volume of water a person drinks. Of all freshwater with drawn for human use, industrial and house hold uses account for 20 and 10 percent respectively, while agriculture consumes on average around 70 percent and much more in some locations. Furthermore, it is expected that by 2030 the global average agricultural water withdrawal for irrigation itself will be some 14 percent higher. India, with a population of approximately 1.35 billion, is facing four different ecological threats including water stress, droughts and cyclones. Nearly 40 per cent of India's population or 600 million people live in areas affected by reduced rainfall and droughts
India will need to feed approximately 394 million more people by 2050, and that’s going to be a significant challenge. Nutrient deficiencies are already widespread in India today—30 percent or more are anemic—and many regions are chronically water-stressed. Making matters worse, evidence suggests that monsoons are delivering less rainfall than they used to. But a study published today in Science Advances shares a brighter outlook: replacing some rice with less thirsty crops could dramatically reduce water demand in India, while also improving nutrition.
Starting in the 1960s, a boom in rice and wheat production helped reduce hunger throughout India. Unfortunately, this Green Revolution also took a toll on the environment, increasing demands on the water supply, greenhouse gas emissions, and pollution from fertilizer.
“If we continue to go the route of rice and wheat, with unsustainable resource use and increasing climate variability, it’s unclear how long we could keep that practice up,” says Kyle Davis, a fellow at Columbia University’s Earth Institute and lead author on the new study. “That’s why we’re thinking of ways to better align food security and environmental goals.”
The study addresses two key objectives of the Indian government: to reduce undernourishment and improve nutrition, and to promote sustainable water use.
Davis and his colleagues studied six major grains currently grown in India: rice, wheat, maize, sorghum, and pearl and finger millet. For each crop, they compared yield, water use, and nutritional values such as calories, protein, iron, and zinc.
Rice tends not to be a water-efficient crop. They found that rice is the least water-efficient cereal when it comes to producing nutrients, and that wheat has been the main driver in increasing irrigation stresses.
The potential benefits of replacing rice with alternative crops varied widely between different regions, depending on how much the crops could rely on rainfall instead of irrigation. But overall, the researchers found that replacing rice with maize, finger millet, pearl millet, or sorghum could reduce irrigation water demand by 33 percent, while improving production of iron by 27 percent and zinc by 13 percent.
In some instances, those improvements came with a slight reduction in the number of calories produced, because rice has been bred to have higher yields per unit of land. So in some regions there’s a trade off between water and land use efficiency, but Davis thinks that with more attention from scientists, the alternative crops could develop higher yields as well. For now, rice replacement isn’t a one-size-fits-all solution, but something that should be evaluated on a case-by-case basis for each district, he said.
In many places in India, grains such as pearl millet could use less water and be more nutritious than rice. In addition, the team wants to study Indian food preferences, to see if people would be willing to incorporate more of these alternative cereals into their diets. Davis is hopeful; “There are places around India where these crops continue to be consumed in pretty large amounts,” he says, “and there were even more a generation or two ago, so it’s still within the cultural memory.”
Momentum is already growing in support of alternative grains. Some Indian states are have already started pilot programs to grow more of these crops, and the Indian government had called 2018 the ‘Year of Millets.’
In the scope of Indian agriculture, a variety of crops is cultivated in India due to the vastly distinct weather and soil conditions that are available in various topographies across the country. These crops are majorly divided into food grains, cash crops, plantation crops and horticulture crops. Water is one of the essential resources that are required for proper growth of these crops. The majority of the farmers are still dependant on growing water intensive crops. Irrigation water, exclusive of precipitation and stored moisture, is required to meet the consumption rate of a crop during its growth period. But the amount of irrigation water required differs for each plant, not only because different plants need to survive different environments, but also because each plant has its own unique physical features. The rural Indian population is largely dependent on agriculture as its primary source of livelihood. Agriculture is one of the major contributors to India’s GDP, with an 18% share (KPMG report), this population plays an integral role in the Indian Economy.
In this regard, we would like to highlight some of the most water intensive crops that are popularly grown by Indian farmers
Rice acts as one of the most important staple food in the world and India is one of its largest producers. However, its production requires a great quantity of water. The rise in population has led to an increase in the demand for food crops; in turn escalating the amount of water required for irrigating them. Traditional farming needs 3,000 to 5,000 liters of water to produce a kilo of rice. The crop requires flooded soil for its growth as it suppresses weed growth and increases the uptake of nutrients from the soil for better yield. In India, it is grown in Jharkhand, West Bengal, Uttar Pradesh, Andhra Pradesh, Punjab, Bihar, Orissa, Chhattisgarh, Assam, Tamil Nadu and Haryana.
The researchers modelled the impact of different crops on water use and the provision of four key nutrients—iron, zinc, protein, and calories—across several regions of India. When compared with other cereal crops like sorghum, maize, and millet, the wheat and rice just didn’t stack up, water- and nutrition-wise. In particular, the researchers found that rice provided the least nutrition for the amount of water consumed. Replacing rice paddies with other grains, the study found, would collectively cut irrigation by 33% across the country. This would also boost the quantity of available nutrients overall, crucially increasing iron by 27%, and zinc by 13% (but protein by only 1%).
Also known as ‘white gold’, Cotton is a Kharif crop. India is one of the largest producers as well as exporters of cotton yarn. On an average, India uses 22,500 liters of water to produce 1 kg of cotton. Most Indian cotton is grown in drier regions. States cultivating this crop the most are Gujarat, Maharashtra, Andhra Pradesh, Haryana, Madhya Pradesh, Punjab, Rajasthan, Karnataka, Tamil Nadu and Orissa.
India is the second largest producer of this popular cash crop. It has one of the longest growing periods and its growth can come to an untimely halt if there is a shortage of water. Generally crops require 300-500mm of rainfall/water for their growth; however, sugar cane requires 1,500-2,500mm of rainfall/water to complete the growth cycle. Therefore, the crop requires 1500-3000 liters of water to produce a kilo of sugarcane! In India, Uttar Pradesh, Maharashtra, Karnataka, Tamil Nadu, Andhra Pradesh, Bihar, Gujarat, Haryana, Uttarakhand, and Punjab are the major producers of this crop. Sugar cane is a deep-rooted crop grown in warm countries which, unlike most seasonal crops, remains in the soil all year round and as a result uses a lot of water. Even in areas where sugarcane is not irrigated, the crop can have a great impact on river flow as it reduces run-off from the catchment into rivers and draws heavily on ground water resources. Sugar is also produced from sugar beet, especially in Europe, and alternative sweeteners are also made from other crops such as maize.
With 12 million tons of production; Soybean is one of the fastest growing crops in India. The crop is considered to be well suited for Indian soil. A major source of protein, vegetable oil, and animal feed, the crop requires around 900 liters of water for 1 kilo worth produce. This crop is majorly grown in Madhya Pradesh, Maharashtra, and Rajasthan.
After the Green Revolution, wheat production in India has been on the rise. After rice, wheat is the most consumed crop by the Indian population. Not just that, our country is also one of the largest exporters of all varieties of wheat, making us the second largest producer of the crop worldwide. However, the fact that cannot be ignored is that 900 litres of water is required to produce 1kg of wheat. In India, this crop’s production is mainly in the northern region – Uttar Pradesh, Punjab, Madhya Pradesh, Haryana, Rajasthan, Bihar, Gujarat, Maharashtra, West Bengal and Uttarakhand are the major producers of this crop.
We can, therefore, see how Economic growth is indirectly dependent on fresh water. There needs to be an understanding that for greater agricultural productivity, for there to be a better harvest, there needs to be enough water. If water is used up by such water-intensive crops, there will come a time when there will be no water for agriculture. Most of these crops are grown in dry areas, which do not receive ample rainfall, and the farmers are either dependent on other freshwater sources or groundwater pumps. In a country like India, where 76 million people do not have access to safe drinking water, using up a great amount of water in such crops seems unfair. Water intensive agriculture takes away liters of water that can be used to help a significant population survive. Cultivation of these crops has even endangered some areas of water scarcity. In fact, due to intense drought conditions year after year, there have been multiple pleas by local officials for farmers to switch to pulses and oilseeds in Rampur. Tamil Nadu government has also asked farmers to switch to millets and pulses from rice, as the new crops will use less water and are as nutritious. However, in some areas, switching to different crops cannot be considered an ideal solution because of climatic limitations, soil requirements etc, therefore, a switch to better irrigation techniques like drip irrigation can be taken up. Furthermore, groundwater irrigation pumps are either dependent on irregular grid electricity or diesel, causing additional strain on the current environmental conditions. Solar powered pumps can be considered a model solution to overcome that problem. The water needs of these crops need to be considered to formulate an immediate solution.
By 2050, the country will have to feed almost 400 million more people, and already 30% of the population are undernourished because they lack enough iron in their diets. What’s more, water availability has become increasingly threatened as groundwater extraction intensifies, and climate change makes rainfall less predictable. That puts wheat and rice–two of the country’s most important and thirsty crops–under threat. But the new Columbia University-led research shows that with some agricultural tweaks, India might be able to dodge this fate.
To switch crops on this scale, India would also have to reckon with its deep-seated, historical appetite for rice and wheat, the researchers say. In the 1960s, an agricultural boom in the country suddenly elevated these two crops to star status. That’s since been upheld by government subsidies which encourage farmers to keep producing these valuable staples–especially since India is the world’s biggest exporter of rice.
If Indian farmers replaced plots of water-guzzling rice and wheat with less thirsty crops, this moderate shift could cut down the country’s water consumption by a whopping one-third. Plus, crop-swapping would have the added benefit of boosting national nutrition, a new Science Advances study finds.
Now, decades later, the country is having to deal with excessive water use (and compromised nutrition) as the flip side to this agricultural boom. With climate change now complicating things further, having a greater variety of staple crops could make India’s agricultural sector more resilient–whereas relying on just one or two major staple crops would leave the agricultural system vulnerable to drought and other threats. And, if this new crop model works, India could become an example for other parts of the world.
India’s agricultural sector currently uses about 90% of total water resources. Irrigated agriculture has been fundamental to economic development, but unfortunately caused groundwater depletion. Due to water pollution in rivers, India draws 80% of its irrigation water from groundwater. As water scarcity becomes a bigger and bigger problem, rural and farming areas will most likely be hit the hardest. Thus far, food security has been one of the highest priorities for politicians, and the large farming lobby has grown accustomed to cheap electricity, which allows extremely fast pumping of groundwater, which is something they are unwilling to give up for the sake of water conservation. If India wants to maintain its level of food security, farmers will have to switch to less water intensive crops. Otherwise India will end up being a net importer of food, which would have massive ramifications for the global price of grain.