Micro Irrigation Systems in India

In this chapter, the authors raise several questions related to adoption of MI systems in India vis-à-vis the sections of the farming community, which adopts the technology and the sections which do not adopt. The authors also raise several questions relating to the methodology adopted currently for analyzing the physical, agronomic and economic benefits from MI, and assessing the future potential of MI systems’ in terms of saving water from agriculture and making more water available for environment, in the wake of the wider recognition of the distinction between ‘notional water saving’ and ‘real water saving’ from efficient irrigation technologies. It also deals with the issue of positive/negative externalities and real ‘social benefits’ and costs associated with the use of MI systems, a major justification for provision of heavy capital subsidies for its purchase by the farmers.

In this chapter, we attempt to determine the potential benefits from the use of MI systems in India. This is done through assessing: (a) the conditions that are favourable for MI system adoption and the constraints to adoption; (b) the field level and aggregate level impacts of the systems on water use; and (c) the yield and economic benefits from adoption of the system. The research also assesses the future potential coverage of MI systems in India. An analysis of the scope of MI adoption in erstwhile Andhra Pradesh, including its likely impact on water saving is also attempted. The constraints in MI system adoption are: (i) lack of independent source of water and pressurizing device for many farmers; (ii) poor quality of groundwater in many semiarid and arid regions; (iii) the mismatch between water delivery schedules in surface irrigation systems and irrigation schedules required in MI systems; (iv) cropping systems that dominate field crops in semi-arid regions; (v) dominance of small and marginal farmers, and small plot sizes; (vi) low opportunity costs of pumping groundwater due to lack of well-defined water rights; (vii) negative technical externalities in groundwater use; (viii) poor extension services; and (ix) poor administration of subsidies. The future potential of MI systems to improve basin water productivity is primarily constrained by the physical characteristics of the basins vis-à-vis the opportunities they offer for real water-saving at the field and basin level water productivity improvements, and area under crops that are conducive to MI in those basins. The potential area under water saving MI in India was assessed at 7.98 million hectares. For erstwhile Andhra Pradesh, the potential estimated was estimated to be a mere 0.88 million hectares, in well irrigated areas. What is more important is that adoption is unlikely to result in real water saving at the farm level as farmers would expand the area under irrigation, in lieu of the fact that the area irrigated by groundwater is a small fraction of the cultivable land in the region.

The water use efficiency under conventional method of irrigation predominantly practiced in Indian agriculture is very low due to substantial conveyance and application losses. Recognizing the consistent decline in utilizable water resources for irrigation and increase in demand for water from other competing use sectors, a number of demand management strategies have been introduced to increase water use efficiency in agriculture. One such method is drip method of irrigation (DMI). DMI is proved to be an efficient method in increasing water use efficiency as compared to the flood method of irrigation (FMI) and saving water at the field level. The adoption of DMI has been relatively high in Maharashtra state where it is used mainly for cultivating sugarcane, grapes, banana and cotton. Although more than 20 years have passed since the introduction of state-specific promotional scheme for DMI in the State, not many studies have analysed its overall status. This Chapter makes an attempt to address such questions as: What is the current status of DMI in the state in relation to other Indian states? Is DMI economically viable for farmers? Can farmers adopt DMI without government subsidy? The analysis shows that the productivity of crops, saving of water and electricity as well as profits were significantly higher for sugarcane, grapes, banana and cotton cultivated under DMI than that under FMI. The discounted cash flow technique employed to find out the viability of drip investment shows that DMI is economically viable for all the four crops even without capital subsidy.

This Chapter has attempted to review the status of micro-irrigation in Karnataka, and analyse its potential and constraints in adoption by the farmers. It relied on the secondary data and other published information. Heavy electricity subsidy in the farm sector and the resultant preference of well irrigators for high water consuming crops is reported to be causing groundwater over-use in the State. The net area irrigated through groundwater increased substantially from 1.5 lakh hectares (16.0 % of net sown area) in 1962–63 to 16.2 lakh hectares (53.0 % of net sown area) in 2009–10. Analysis of cropping pattern of the last five decades reveals the marked shift from low water intensive crops to high water requiring crops such as sugarcane and vegetables. Both the Karnataka state water policy and agricultural policy take cognizance of the problem of groundwater depletion and suggested among others, the promotion of drip and sprinkler irrigation. Various subsidy schemes to encourage the farmers to adopt micro-irrigation are in vogue. But, the level of adoption of drip and sprinkler irrigation systems remains low. Some of the reported constraints for low adoption are high capital cost, lack of appropriate design for different soil conditions, delay in release of subsidy and small land holding size.

The pronounced decline in groundwater-level in Gujarat has been a major cause of social divide, as only wealthy farmers were able to meet the increased groundwater drilling and pumping costs in earlier decades of agricultural development. Though water saving technologies in the form of micro irrigation systems (MIS) was reckoned as a long-term strategy to address problems of groundwater scarcity, the wide-scale promotion of the same met with setbacks initially, as MISs were capital intensive in nature and hence, unaffordable for smallholders. However, the scenario had undergone significant change over the past two decades in particular, with MISs becoming less sophisticated and less capital intensive and thus leading to a significant increase in its adoption in Gujarat and other states. In this background, the Chapter presents an overview of the status of adoption of MIS and its socio-economic impacts on agriculture as well as water sector in the state of Gujarat. A major concern that the Chapter puts forth is ‘whether and (if so) how far the MIS interventions in the form of sprinklers and drips would create positive outcomes by reducing the overdraft of groundwater for agriculture purposes in the state?'. The chapter also presents the results of a rapid assessment of the impacts of the MIS in the Banaskantha district covering a sample of 375 farmers who have adopted the MIS implemented by the GWRDC, an agency set up by the state government for promotion of MIS and other water management interventions.

Micro irrigation has received much attention from the policy makers and others for its perceived ability to improve water productivity. Realising the significance of using micro irrigation system as a demand management strategy, an attempt has been made in this chapter to examine the social benefit-cost analysis of drip irrigation. As found in many earlier studies, the drip irrigation resulted in significant increase in yield over the flood method of irrigation. The analysis of economics of crop cultivation in drip and control villages revealed that the drip method of irrigation has significant impact on resource use, cost of cultivation, yield of crops and farm profitability. The social benefit-cost analysis revealed that the social benefits exceed the social costs in the water and labour scarce regions. Thus, one can conclude that the drip irrigation is a viable and more beneficial in regions where there is more water scarcity. The social benefit-cost ratio (SBCR) in over-exploited regions is 5.19 and 4.97 respectively without and with subsidy at a discount rate of 2 %, while it is 4.56 and 4.33 in the semi-critical regions. This clearly shows that wider adoption of drip irrigation produces sufficient social benefits and continuing support through subsidies will save water and energy and help achieve sustainable management of groundwater resources. Hence, continuing public support for the wider adoption and promotion of drip irrigation technologies appears warranted.

The state of Gujarat in western India falls mostly in arid and/or semi-arid regions, where half of the rural households depend on agriculture. The relatively low rainfall regions in the state receive rainfall for about 15–20 days during the monsoon with high inter-annual variation. Groundwater irrigation was promoted on a large scale to mitigate the impacts of droughts. Intensive use of groundwater had resulted in its depletion and contamination. To address the worsening groundwater problem, the state government has been promoting micro-irrigation systems (MIS) among the farmers in recent years, through the Gujarat Green Revolution Company (GGRC) Limited, which acts as a nodal agency, using capital subsidy in the range of 50–75 %. There are not many studies that investigate the role of subsidy in enhancing the rate of adoption of MIS. The ‘seasonality’ dimension in the pattern of adoption and use of MIS is also an important factor that determines the access to the benefits of micro-irrigation, which needs to be investigated. This chapter tries to address this by studying: (i) the influence of subsidy in enhancing the MIS adoption rate in the recent years; and (ii) the effects of seasonality and cropping pattern on accessing the benefits from MIS, using an empirical study in Banaskantha district of north Gujarat. The study covered 122 public tubewells with MIS, and 355 farmers randomly selected as sample. The results suggest that: (a) subsidy significantly increased adoption of MIS in recent years; and (b) the environmental and socio-economic benefits of MIS adoption was largely confined to certain specific crops and the seasons. From a policy perspective, this analysis could help in identifying and promoting specific crops/cropping patterns that can produce better outcomes of investments.

While groundwater and energy use in irrigated agriculture has gone up exponentially during the past 2-3 decades, pervasive energy subsidies combined with lack of regulation of groundwater withdrawal is resulting in both groundwater over-exploitation and inefficient and wasteful use of energy. Of late, options such as the use of solar irrigation pumps in conjunction with drip systems are being suggested to address the groundwater energy nexus conundrum. The idea being proposed is that farmers could produce electricity using solar PV systems, use it for pumping groundwater and sell the excess electricity to the grid, using ‘net metering’, thereby creating incentive for efficient use of energy and groundwater, while reducing the power subsidy burden on the utilities. Empirical analysis explores whether solar pumps are technically feasible and also whether they are economically viable under the existing energy and water pricing policies. It also examines the degree of incentive farmers would have to make best use of drip systems for improving water use efficiency, while using solar energy to run their pumps.

In this chapter, the authors summarizes the complex considerations involved in assessing the real water saving from adoption of MI technologies, and thereby highlighting the challenges in assessing the real potential of MI technologies in India. It summarizes the issues emerging from the analysis presented in the previous chapters in terms of areas for future research. Particularly, the need to quantify crop water requirement for various horticultural crops, and the need to understand the economic viability of using solar pumps for micro irrigation systems are highlighted. Given the limits to expanding the area under micro irrigation systems in India, the authors also argue that there is a need to focus on other water saving technologies in agriculture, in terms of understanding the benefits and impacts.