The journey towards sophisticated agriculture in India is incomplete without addressing age-old irrigation practices. The sector’s high dependence on water and energy resources makes it vulnerable to climate change. Recognising this, various avenues for sustainable and smart irrigation have emerged over the past decade. The central government is creating opportunities for farmers to use clean energy sources such as solar power through supportive schemes. The state governments are exploring the high-value potential of wastewater for irrigation purposes, while more advanced technologies are being developed for to examine irrigation methods.
Solar irrigation practices
The high potential of solar power usage is rapidly being tapped in India’s irrigation sector. The use of the renewable energy source for groundwater extraction has some important environmental and economic benefits. Its use reduces the carbon footprint and financial pressure with electricity subsidies and diesel imports. It is estimated that this practice can reduce carbon emissions by up to 25.3 million tonnes (mt) annually. Therefore, the government is paving the way to make solar-powered irrigation mainstream among farmers. Its Pradhan Mantri Kisan Urja Suraksha evam Utthan Mahabhiyan (PM-KUSUM) scheme, aimed at de-dieselising farms, guarantees a central government subsidy of up to 30-50 per cent of the total cost for the installation of standalone solar pumps as well as solarisation of existing grid-connected agricultural pumps. Under the scheme, a total solar capacity of 256.78 MW has been installed under Component A, while 397,437 standalone pumps have been deployed under Component B and 2,644 individual solar pumps under Component C, as of June 2024.
Another example of solar-powered irrigation is the Bahraich district of Uttar Pradesh. With the rising unpredictability of monsoons and associated costs of sourcing water, the district has adopted sustainable irrigation methods. As of December 2023, around 97 solar irrigation systems are being used in the district, benefitting 8,700 farmers with an irrigation coverage of 1,872 acres.
Mainstreaming the use of recycled wastewater
The constrained and depleting sources of freshwater and groundwater for irrigation have led to a shift in attention to alternative water sources. In recent times, there has been increased awareness about the value of the high amount of wastewater generated in the country. Many state governments are exploring innovative solutions to reuse treated wastewater for irrigation via an underground pipeline conveyance system. The use of recycled wastewater in irrigation is also estimated to have reduced around 1.3 mt of greenhouse gas emissions and improved water use efficiency.
In view of this, the Chandigarh government has started the upgradation of six sewage treatment plants (STPs) to expand the supply of treated wastewater in the city in March 2024. This would primarily be used for irrigation purposes after undergoing chemical treatment and sedimentation. The biochemical oxygen demand of this water should be below 10 mg for suitable use in irrigation and related activities. The project, worth Rs 715.8 million, is likely to save 20-25 million gallons of potable water per day by increasing the use of treated wastewater for irrigation and industrial activities. Some of these STPs are located at Raipur Kalan, 3BRD, Maloya and Diggian.
The Haryana government has implemented a policy to reuse TWW for multiple purposes including irrigation to meet its water conservation targets. Some other state governments have also emphasised recycling wastewater in their wastewater treatment and reuse policies. According to the State Sewerage and Wastewater Policy of Rajasthan, wastewater treatment must aim to generate water fit for reuse in irrigation. This treated wastewater must meet WHO guidelines as a minimum requirement. Likewise, the Treated Wastewater Policy of Punjab prioritises the reuse of treated wastewater for unrestricted irrigation. It specifies that the crops irrigated with TWW or a blend of freshwater must be selected to suit the economics of reuse operations, among other factors.
Technologies supporting optimised irrigation
The increasing water scarcity in India has pushed the agricultural sector to explore new-age technologies for optimising water usage in irrigation. Technologies such as artificial intelligence and internet of things (IoT)-based sensors allow the monitoring and analysis of soil conditions and weather patterns, helping farmers determine the right amount and timing for watering farms. It is estimated by the Ministry of Agriculture and Farmers’ Welfare that this optimised irrigation can reduce water wastage by up to 35 per cent. Further, IoT sensors are being deployed in India for assessing the levels of soil moisture, temperature and humidity. These smart farming solutions are also being explored in the automation of irrigation systems, among other practices.
In a recent development, the Centre for Development of Advanced Computing, India, launched the smart farm system in April 2024 as a step towards sustainable agriculture and irrigation. This indigenously developed system will allow farmers to plan irrigation activities on the basis of environmental and soil conditions, ensuring maximum yield by monitoring different parameters like soil moisture, pH, atmospheric temperature, humidity, wind speed and direction, and rain. This system also takes corrective measures and informs farmers via a graphical display unit. It is equipped with a wireless interface for collecting data from wireless sensor nodes. As a result, farmers receive alerts through SMS regarding important situations at the farm. They can even control the working of pumps and valves remotely through their mobile applications enabled with a high speed network.
Underlying challenges
The pursuit of sustainability in irrigation comes with its own set of challenges. While the sector is progressing towards the adoption of clean energy, several critical shortcomings remain. For instance, despite efforts to subsidise solar irrigation, farmers still need to make a significant investment in solar pumps. To help recover this capital cost, several states buy excess electricity from farmers. However, the majority of farmers are unaware of this and the process of selling excess energy back to the grid is still complex. This has only been implemented at the pilot stage and awaits large-scale deployment. In fact, only 2.6 per cent of the solar power potential for irrigation has been tapped, out of a total potential of 102.4 GW in India.
Besides, solar irrigation has counter effects on existing water resources. Solar irrigation policies focus on increasing groundwater use in water-rich regions, which could lead to groundwater depletion in the future. Moreover, the use of treated for irrigation is hindered by the significant gap in wastewater treatment capacity. Currently, more than 50 per cent of the wastewater generated in India remains untreated, leaving the large potential for its reuse untapped.
Future outlook
The government is ambitiously working to improve the current state of agriculture by promoting sustainable irrigation practices. It is receptive to and encouraging to the use of smart solutions to rationalise irrigation. The sector is experimenting with technology-based water resource management including canal automation, GIS mapping, data integration and drone-based solutions.
Furthermore, the Ministry of Agriculture and Farmers’ Welfare is planning to revamp the Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) into a smart irrigation scheme. This would increase on-farm water use efficiency by around 20 per cent and improve the micro-irrigation potential to cover 70 million hectares with the larger deployment of advanced technologies. The joint implementation of micro-irrigation and solar power technologies will also contribute to the net zero emissions by 2070 target. The industry believes that combining micro-irrigation and solar pumps would yield better economic, ecological and environmental benefits due to the strong complementarity between PM-KUSUM and the PMKSY, implemented by two different ministries.
Shubhangi Goswami
