A recent study by Harvard University, the Jet Propulsion Laboratory, Environmental Defense Fund (EDF), the University of Michigan, the Public Health Foundation of India, the International Maize and Wheat Improvement Center (CIMMYT), Columbia University, and the University of California, Los Angeles, has determined the environmental impact of a government policy of delayed rice planting in northwest India.
“We have shown that the groundwater and air quality crises are major regional issues and are interconnected,” said co-author Balwinder-Singh, former Cropping System Scientist at the International Maize and Wheat Improvement Center (CIMMYT) in New Delhi. “But there is still a path to clearer skies and safer water practices. Local solutions include planting rice varieties that either grow more quickly or need less water. Promoting less water-demanding crops like maize would be helpful in zones with severe groundwater depletion.”
Data collector reading data from offline groundwater level logger – one of the three tested monitoring technologies. (Credit: Subash Adhikari/CIMMYT)
Based on a pilot study regarding the feasibility and cost effectiveness of several groundwater monitoring approaches for agriculture in Nepal’s Terai region, a water and food security specialist who led the research has recommended the use of phone-based systems.
Speaking to diverse experts at the recent World Water Week 2022 in Stockholm, Sweden, Anton Urfels, a systems agronomist at the International Maize and Wheat Improvement Center (CIMMYT), said that manual monitoring with phone-based data uploading is relatively low-cost and effective and could be scaled up across the Terai.
“One alternate monitoring approach studied — online data uploading — has substantially lower staff time requirements and technology costs and higher temporal resolution than phone-based monitoring, but does not provide real-time data and entails high technical skills, capital costs, and risks of theft and damage,” said Urfels in his presentation, ‘Upgrading Groundwater Monitoring Networks in Low-Income Countries’.
Urfels and partners also developed a prototype of an open-source groundwater monitoring dashboard to engage stakeholders, help translate raw data into actionable information, and detect water depletion trends.
Water has become a key part of food research and innovation, critical for sustainable and ecological intensification in agriculture, according to the scientist.
“Collecting groundwater data is difficult and the technology for monitoring is unreliable, which impairs effective modeling, decision-making, and learning,” Urfels explained. “Like other countries in the region, Nepal is increasing its agricultural groundwater consumption, particularly through private investment in irrigation wells and pumps that open irrigation to more farmers. This and climate change have altered groundwater recharge rates and availability, but national data on these trends are incomplete.”
An extensive lowland region bordering India and comprising one-fifth of the nation’s territory, the Terai is Nepal’s breadbasket.
Held yearly since 1991, World Water Week attracts a diverse mix of participants from many professions to develop solutions for water-related challenges including poverty, the climate crisis, and biodiversity loss. The 2022 theme was “Seeing the Unseen: The Value of Water”.
“I’d recommend more pilot studies on phone-based groundwater monitoring for other areas of Nepal, such as the Mid-hill districts,” Urfels said. “We also need to fine-tune and expand the system dashboard and build cross-sectoral coordination to recognize and take into account groundwater’s actual economic value.”
Urfels said the Nepal Ministry of Energy, Water Resources and Irrigation has requested the nationwide scale-out of a digital monitoring system, and CIMMYT and Nepal experts will support this, as well as improving the system, which would be freely available for use and development by researchers and agencies outside of Nepal.
In India, nearly one-sixth of groundwater reserves has been overexploited and almost one-fifth of them is either in critical or semi-critical condition. For a country that relies heavily on groundwater for drinking and irrigation, these statistics are close to a death sentence.
India’s water crisis, however, is not unique in the region. Population growth, coupled with increasing urbanization and industrialization, has made South Asia, one of the most heavily irrigated areas on earth, highly vulnerable to water stress. Moreover, as the effects of climate change are increasingly felt in those countries, agricultural production, even at the current level, may not be sustainable.
Against this background, ensuring that water resources are used efficiently and sustainably is key to meet the world’s growing demand. Over the last decades, traditional systems of irrigation have given way to more efficient drip irrigation systems that deliver the right amount of water and nutrients to the plant’s root zone. But as farm labor shortages become more severe, investing in automated irrigation systems — which promise increased production rates and product quality — will be the only way to ensure the sustainability of agricultural production systems worldwide.
A new article co-authored by a team of researchers from the International Maize and Wheat Improvement Center (CIMMYT) and the Thapar Institute of Engineering and Technology synthesizes the available information related to the automation of drip irrigation systems and explores recent advances in the science of wireless sensor networks (WSN), the internet of things (IoT) and other communication technologies that increase production capacity while reducing costs.
“Bundling both elements — drip irrigation and automation — in water application can lead to large savings in irrigation and boost water efficiency, especially in high water-consuming, cereal-based systems like the Indo-Gangetic Plains,” explained M.L. Jat, a principal scientist at CIMMYT and one of the authors of the review.
Investing in data and youth
Smart irrigation technologies, including sensors and the IoT, allow farmers to take informed decisions to improve the quality and quantity of their crops, providing them with site-specific data on factors like soil moisture, nutrient status, weed pressure or soil acidity.
However, this information is still limited to certain soil types and crops. “To upgrade drip irrigation systems elsewhere, especially in ‘water-stressed’ regions, we need additional agricultural background data in those areas,” Jat pointed out. “That’s the only way we can effectively customize innovations to each scenario, as one size does not fit all.”
Making this data available to and readable by farmers is also essential. Here, young people can become very good allies, as they tend to be more technologically savvy and used to working with large volumes of information. “Not only are they more skilled to integrate agricultural data into decision-making, but they can also help older farmers adopt and trust intelligent irrigation systems,” Jat concluded.
Long-term research platform in Karnal, India, by H.S. Jat, Principal Scientist at ICAR-CSSRI. (Photo: ICAR-CSSRI and CIMMYT)
Incentives against subsidies
With increasing water shortages worldwide, making the most out of every drop becomes an urgent priority. But in countries where irrigation systems are highly subsidized, farmers may struggle to see this urgency. India, for instance, subsidizes the cost of energy to pump water for farming, thus encouraging smallholders to extract more than they need.
How do we incentivize farmers in these countries to embrace water-efficient technologies?
According to Jat, using the “scientific card” can work with smallholders who, after having farmed for decades, may not change their minds automatically. “These people may be reluctant to accept incentives for water-efficient mechanisms at first, but they will surely be interested in more scientific approaches,” Jat explained, stressing that “the emphasis must be on the science, not on the technology.”
Designing profitable business models can also incentivize producers to embrace more efficient mechanisms. Farmers who have enjoyed irrigation subsidies for decades may not see any profit in trying out new technologies — but what if they are given the chance to become champions or ambassadors of these agricultural innovations? “That brings in a whole new perspective,” Jat said.
Apart from incentivizing farmers, good business models can also draw the attention of large companies, which would bring investment to boost research and innovation in drip irrigation. “More and more businesses are getting interested in smart agriculture and low emission farming, and their inputs can help conceptualize the future of this field,” he observed.
In Nepal, agriculture contributes to a third of gross domestic product and employs about 80% of the rural labor force. The rural population is comprised mostly of smallholder farmers whose level of income from agricultural production is low by international standards and the country‘s agricultural sector has become vulnerable to erratic monsoon rains. Farmers often experience unreliable rainfall and droughts that threaten their crop yields and are not resilient to climate change and water-induced hazard. This requires a rapid update of the sustainable irrigation development in Nepal. The Cereal Systems Initiative for South Asia (CSISA) Nepal COVID Response and Resilience short-term project puts emphasis on identifying and prioritizing entry points to build more efficient, reliable and flexible water services to farmers by providing a fundamental irrigation development assessment and framework at local, district and provincial levels.
Digital groundwater monitoring system and assessment of water use options
Digital system of groundwater data collection, monitoring and representation will be piloted with the government of Nepal to facilitate multi-stakeholder cooperation to provide enabling environments for inclusive irrigation development and COVID-19 response. When boosting the irrigation development, monitoring is fundamental to ensure sustainability. In addition, spatially targeted, ex-ante assessments of the potential benefits of irrigation interventions provide insights by applying machine-learning analytics and constructing data-driven models for yield and profitability responses to irrigation. Furthermore, a customized set of integrated hydrological modeling and scenario analyses can further strengthen local, district and provincial level assessment of water resources and how to build resilient and sustainable water services most productively from them.
Toward a systemic framework for sustainable scaling of irrigation in Nepal
Through interview and surveys, the project further builds systemic understanding of the technical, socioeconomic and institutional challenges and opportunities in scaling water access and irrigation technologies. This will contribute to the construction of a comprehensive irrigation development framework, achieved by the collective efforts from multiple stakeholders across different line ministries, levels of government and local stakeholders and water users. Together with the technical assessments and monitoring systems, the end goal is to provide policy guidelines and engage prioritized investments that ensure and accelerate the process of sustainable intensification in irrigation in Nepal.
A recent study of the groundwater in India revealed that, by 2025, large areas of the north-western and southern parts of the country will have “critically low groundwater availability”, leading to a decrease in cropping that will ultimately cause an imbalance in the food security for millions.
Groundwater is essential for Indian agriculture and rural livelihoods, but groundwater levels are declining. Simply providing canal irrigation as a substitute irrigation source will likely not be enough to maintain current production levels.
Water pumped from a deep irrigation well, called a tube well, at a wheat farm in west India’s Gujarat state. (Photo: Meha Jain)
India is the world’s second-largest producer of wheat and rice and is home to more than 600 million farmers. The country has achieved impressive food-production gains since the 1960s, due in part to an increased reliance on irrigation wells, which allowed Indian farmers to expand production into the mostly dry winter and summer seasons.
But those gains have come at a cost: The country that produces 10% of the world’s crops is now the world’s largest consumer of groundwater, and aquifers are rapidly becoming depleted across much of India. Indian government officials have suggested that switching from groundwater-depleting wells to irrigation canals, which divert surface water from lakes and rivers, is one way to overcome projected shortfalls.
The authors estimate that if Indian farmers lose all access to groundwater in overexploited regions, and if that irrigation water is not replaced with water from other sources, then winter cropped acreage could be reduced by up to 20% nationwide. However, that scenario seems highly unlikely and was included in the study only as an upper-bound estimate.
It seems more likely that any future groundwater shortfalls would be at least partially offset by increases in canal irrigation. But even if all Indian regions currently using depleted groundwater switch to canal irrigation, winter cropped acreage could still decline by 7% nationwide and by 24% in the most severely affected locations, according to the researchers.
Water alternatives needed
“Our results highlight the critical importance of groundwater for Indian agriculture and rural livelihoods, and we were able to show that simply providing canal irrigation as a substitute irrigation source will likely not be enough to maintain current production levels in the face of groundwater depletion,” said study lead author Meha Jain, an assistant professor at the University of Michigan’s School for Environment and Sustainability.
“We need coordinated efforts to solve this water availability and food security issue, which should be supported by science-led policy decisions on what strategies and technology solutions to scale out to improve irrigation efficiency,” said co-author Balwinder Singh, a Cropping Systems Simulation Modeler at the International Maize and Wheat Improvement Center (CIMMYT).
The study analyzed high-resolution satellite imagery and village-level census data and focused on winter cropped acreage. While nearly all Indian farmers plant crops during the monsoon to take advantage of seasonal rains, winter agriculture is mainly reliant on groundwater irrigation and now accounts for 44% of the country’s annual cropped acreage for food grains.
“These findings suggest that other adaptation strategies, in addition to canal expansion, are needed to cope with ongoing groundwater losses,” Jain said.
The possibilities include switching from winter rice to less water-intensive cereals, increased adoption of sprinklers and drip irrigation to conserve water in the fields, and policies to increase the efficiency of irrigation canals.
While groundwater depletion is becoming a global threat to food security, and the extent of current and projected groundwater depletion are well documented, the potential impacts on food production remain poorly quantified. The study is the first to use high-resolution empirical data, including census data about the irrigation methods used in more than 500,000 Indian villages, to estimate the crop production losses that may occur when overexploited groundwater is lost.
“Understanding the complex relationship between food security and water availability is crucial as we prepare for future rainfall variability due to global climate change,” said co-author Gillian Galford of the University of Vermont.
The proliferation of deep (>30 meters) irrigation wells called tube wells since the 1960s has enabled Indian farmers to increase the number of seasons when crops are planted in a given year. This increase in “cropping intensity” is credited for much of the country’s food-production gains.
Maps showing state-by-state Indian winter cropped area loss estimates due to groundwater depletion in coming decades, with and without replacement by canals. Darker shades of pink and red indicate greater projected losses. The map on the left (A) shows projected winter cropped acreage losses if all critically depleted groundwater is lost, with no replacement. The map on the right (B) shows projected winter cropped acreage losses if groundwater irrigation is replaced with canals, using national-level regression coefficients. (Graph: Jain et al. in Science Advances 2021)
Big data for food security
The researchers used satellite data to measure Indian winter cropped area, a key determinant of cropping intensity. They then linked the satellite data to census information about the three main types of irrigation infrastructure in India: shallow “dug wells,” deeper tube wells and canals that divert surface water.
Linking the two datasets allowed them to determine the relative efficacy of each irrigation method. That, in turn, enabled them to estimate potential future acreage losses and the ability of canal expansion to fill the gap.
The study’s worst-case scenario found that winter cropped area could decrease by up to 20% nationwide and by 68% in the most severely affected regions, if farmers lose all access to groundwater and if that irrigation water is not replaced from another source. The expected losses would largely occur in northwest and central India, according to the study.
The researchers also found that increased distance from existing irrigation canals is strongly associated with decreased acreage planted with winter crops. In the future, a greater reliance on canals could increase inequities related to irrigation access, according to the authors.
“This suggests that while canals may be a viable form of irrigation for those who live near canals, they may lead to more unequal access to irrigation across villages compared to wells, with negative impacts for those who live farther from canals,” the authors wrote.
In addition, the lakes and rivers that feed irrigation canals rise and fall in response to rainfall variability, unlike deep groundwater wells. So, a greater reliance on canal irrigation in the future would result in increased sensitivity to year-to-year precipitation fluctuations, as well as any long-term trends due to human-caused climate change.
The authors of the Science Advances study, in addition to Jain and Galford, are Ram Fishman of Tel Aviv University; Pinki Mondal of the University of Delaware; Nishan Bhattarai of the U-M School for Environment and Sustainability; Shahid Naeem, Upmanu Lall and Ruth DeFries of Columbia University; and Balwinder Singh of the International Maize and Wheat Improvement Center (CIMMYT).
The work was funded by a NASA New Investigator Award to Jain and two NASA Land Cover and Land Use Change grants, one awarded to R.S. DeFries and one to Jain.
A farmer in Nepal operates a water pump for drip irrigation. (Photo: Sharad Maharjan/IWMI)
Taken together, digital monitoring and readily available data on the status of groundwater resources provide a critical foundation for sustainable irrigation development. While much is known about surface water resources and hydrological and meteorological linkages between the Terai, Mid-Hills and Himalaya regions of the country, Nepal currently lacks a comprehensive system for groundwater resource monitoring.
To respond to this crucial information gap, the International Maize and Wheat Improvement Center (CIMMYT) and International Water Management Institute (IWMI) are partnering with the Government of Nepal’s Groundwater Resources Development Board to conduct a pilot which will develop and test a potential groundwater monitoring system with the goal of identifying an approach which can be gradually scaled out after project completion.
To this end, the project team organized an Inception and Consultation Workshop, which took place virtually on October 14, 2020. This was the first in a series under the Cereal Systems Initiative for South Asia (CSISA) Nepal COVID-19 and Resilience project, funded by the United States Agency for International Development (USAID) Nepal, which supports farmers and rural economies in their response to COVID-19 and addresses, among others, various issues and ways forward for sustainable irrigation development.
The session aimed to introduce the digital groundwater monitoring pilot to local stakeholders, identify monitoring objectives and information needs, facilitate multi-stakeholder and inter-ministerial dialogue, and generate feedback and endorsement of the project plan. Participants were from a wide range of backgrounds and disciplines, and included members of local and national authorities, research centers and universities.
Participants meet virtually at the multi-stakeholder dialogue for Nepal’s Digital Groundwater Monitoring pilot (Photo: Tim Krupnik/CIMMYT)
Madhukar Rajbhandari, director general of the Government of Nepal’s Department of Water Resources and Irrigation, opened the event and during his address highlighted the importance of groundwater irrigation for Nepal’s farming systems and livelihoods. He also captured the challenges which the country faces when developing groundwater irrigation, from polluted water resources through urbanization to lack of market access and the high maintenance costs of irrigation infrastructure. Rajbhandari noted that “agricultural and irrigation projects lack coordination” and expressed his hope that “through this pilot, the way is paved for a collaborative approach to develop practical groundwater solutions for farmers.”
The session introduced participants to the project and its background, leading breakout sessions for two groups: the first containing local, state and national government representatives; the second comprising farmers, researchers and members of industry. Each group was asked to identify the groundwater monitoring objectives and information needs that they would have as different types of users, and to provide feedback and recommendations to improve the project work plan.
The feedback showed that while government representatives are largely interested in developing a better understanding of the groundwater development potential, researchers and farmers are more concerned with possible discharge and water quality. Monitoring frequency was also identified as useful for daily to monthly timescales.
The group discussion revealed participants’ keen interest in consolidating and monitoring groundwater information, which highlights the importance of stakeholder engagement when developing pilots such as these, to ensure that when scaling is achieved, it caters to specific needs. Participants also expressed a strong interest in bringing the results of the project within the ambit of national policy, which would achieve the streamlining of data collection protocols for standardized, publicly accessible, data collection mechanisms.
“It is very encouraging to see such active participation and engagement from all the participants throughout the workshop,” noted Timothy Krupnik, project leader and a senior scientist at CIMMYT. “We look forward to maintaining this momentum, to support Nepal’s efforts in strengthening its capacity for sustainable irrigation.”
A farmer in Banke district during monsoon season drought in 2017. (Photo: Anton Urfels/CIMMYT)
Researchers from the Cereal Systems Initiative for South Asia (CSISA) project have been exploring the drivers of smallholder farmers’ underuse of groundwater wells to combat in-season drought during the monsoon rice season in Nepal’s breadbasket — the Terai region.
Their study, published in Water International, finds that several barriers inhibit full use of groundwater irrigation infrastructure.
Inconsistent rainfall has repeatedly damaged paddy crops in Nepal over the last years, even though most agricultural lands are equipped with groundwater wells. This has contributed to missed national policy targets of food self-sufficiency and slow growth in cereal productivity.
A key issue is farmers’ tendency to schedule irrigation very late in an effort to save their crops when in-season drought occurs. By this time, rice crops have already been damaged by lack of water and yields will be decreased. High irrigation costs, especially due to pumping equipment rental rates, are a major factor of this aversion to investment. Private irrigation is also a relatively new technology for many farmers making water use decisions.
After farmers decide to irrigate, queuing for pumpsets, tubewells, and repairs and maintenance further increases irrigation delays. Some villages have only a handful of pumpsets or tubewells shared between all households, so it can take up to two weeks for everybody to irrigate.
To address these issues, CSISA provides suggestions for three support pathways to support farmers in combatting monsoon season drought:
1. Raise awareness of the importance of timely irrigation
To avoid yield penalties and improve operational efficiency through better-matched pumpsets, CSISA has raised awareness through agricultural FM radio broadcasts on the strong relationship between water stress and yield penalties. Messages highlight the role of the plough pan in keeping infiltration rates low and encouraging farmers to improve irrigation scheduling. Anecdotal evidence suggests that improved pump selection may decrease irrigation costs by up to 50%, and CSISA has initiated follow-up studies to develop recommendations for farmers.
Social interaction is necessary for purchasing fuel, transporting and installing pumps, or sharing irrigation equipment. These activities pose risks of COVID-19 exposure and transmission and therefore require farmers to follow increased safety and hygiene practices, which may cause further delays to irrigation. Raising awareness about the importance of timely irrigation therefore needs to go hand in hand with the promotion of safe and hygienic irrigation practices. This information has been streamlined into CSISA’s ongoing partnerships and FM broadcasts.
2. Improve community-level water markets through increased focus on drought preparedness and overcoming financial constraints
Farmers can save time by taking an anticipatory approach to the terms and conditions of rentals, instead of negotiating them when cracks in the soil are already large. Many farmers reported that pump owners are reluctant to rent out pumpsets if renters cannot pay up front. Given the seasonality of cash flows in agriculture, pro-poor and low interest credit provisions are likely to further smoothen community-level water markets.
Quantified ethnographic-decision tree based on households’ surveys of smallholder decision to use groundwater irrigation in Nepal’s Terai. (Graphic: Urfels et al., 2020)
3. Prioritize regional investment
The study shows that delay factors differ across districts and that selectively targeted interventions will be most useful to provide high returns to investments. For example, farmers in Kailali reported that land access issues — due to use of large bullock carts to transport pumpsets — and fuel shortages constitute a barrier for 10% and 39% of the farmers, while in Rupandehi, maintenance and tubewell availability were reported to be of greater importance.
As drought is increasingly threatening paddy production in Nepal’s Terai region, CSISA’s research shows that several support pathways exist to support farmers in combatting droughts. Sustainable water use can only be brought up to a scale where it benefits most farmers if all available tools including electrification, solar pumps and improved water level monitoring are deployed to provide benefits to a wide range of farmers.
