IWMI Research Report Beyond “More Crop per Drop”: Evolving Thinking on Agricultural 169 Water Productivity Meredith Giordano, Hugh Turral, Susanne M. Scheierling, David O. Tréguer and Peter G. McCornick Research Reports The publications in this series cover a wide range of subjects—from computer modeling to experience with water user associations—and vary in content from directly applicable research to more basic studies, on which applied work ultimately depends. Some research reports are narrowly focused, analytical and detailed empirical studies; others are wide-ranging and synthetic overviews of generic problems. Although most of the reports are published by IWMI staff and their collaborators, we welcome contributions from others. Each report is reviewed internally by IWMI staff, and by external reviewers. The reports are published and distributed both in hard copy and electronically (www.iwmi.org) and where possible all data and analyses will be available as separate downloadable files. Reports may be copied freely and cited with due acknowledgment. About IWMI IWMI’s mission is to provide evidence-based solutions to sustainably manage water and land resources for food security, people’s livelihoods and the environment. IWMI works in partnership with governments, civil society and the private sector to develop scalable agricultural water management solutions that have a tangible impact on poverty reduction, food security and ecosystem health. IWMI Research Report 169 Beyond “More Crop per Drop”: Evolving Thinking on Agricultural Water Productivity Meredith Giordano, Hugh Turral, Susanne M. Scheierling, David O. Tréguer and Peter G. McCornick “Everything has been said before, but since no one listens, one must always start again.” André Gide (quoted in Seckler 1999) International Water Management Institute (IWMI) P O Box 2075, Colombo, Sri Lanka i The authors: Meredith Giordano is Principal Researcher at the International Water Management Institute (IWMI) in Washington, DC, USA; Hugh Turral was formerly Theme Leader - Basin Water Management at IWMI in Colombo, Sri Lanka; Susanne M. Scheierling is Senior Irrigation Water Economist at The World Bank, Washington, DC, USA; David O. Tréguer is Agricultural Economist at The World Bank, Washington, DC, USA; and Peter G. McCornick is Executive Director of the Robert B. Daugherty Water for Food Global Institute at the University of Nebraska, Lincoln, Nebraska, USA. Peter was formerly Deputy Director General – Research (DDG) at IWMI in Colombo, Sri Lanka. © 2017 International Bank for Reconstruction and Development / The World Bank Some rights reserved The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. The World Bank does not guarantee the accuracy of the data included in this work. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory or the endorsement or acceptance of such boundaries. Nothing herein shall constitute or be considered to be a limitation upon or waiver of the privileges and immunities of The World Bank, all of which are specifically reserved. 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A free copy of this publication can be downloaded at http://www.iwmi.org/publications/iwmi-research-reports/ Acknowledgements The authors are grateful for the valuable inputs and insights provided by numerous former and current staff of IWMI and The World Bank and other colleagues on earlier drafts of this report. The constructive comments and suggestions received from two reviewers are also gratefully acknowledged. This report is the joint work of IWMI and The World Bank, and expands on a background paper commissioned by The World Bank as part of a study carried out by the Water and Agriculture Global Practices on Improving agricultural water productivity and beyond: what are the options? Collaborators This research study is a collaboration of the following organizations: International Water Management Institute (IWMI) The World Bank Robert B. Daugherty Water for Food Global Institute Donors This research study was funded by the following: The Water Partnership Program (WPP), a multi-donor trust fund at The World Bank. The CGIAR Research Program on Water, Land and Ecosystems (WLE) with support from CGIAR Fund Donors (http://www.cgiar.org/who-weare/cgiar-fund/fund-donors-2). Contents Summary vii 1. Introduction 1 2. Origins of the Concept and Methodological Developments 3 2.1 From Irrigation Efficiency to Agricultural Water Productivity 3 2.2 A “New Era of Water Resources Management” 6 2.3 Water Accounting and Water Productivity Indicators 7 3. Applied Research 12 3.1 Water Productivity Analysis and Mapping 12 3.2 Pathways to Increase Water Productivity 15 3.3 Water Productivity and Broader Development Objectives 22 4. Lessons Learned: Reflecting on Two Decades of Water Productivity Research 29 5. Conclusions 34 References 36 v v Summary Twenty years ago, the International Water how a focus on agricultural water productivity Management Institute (IWMI), then known has brought greater attention to critical water as the International Irrigation Management scarcity issues, and the role of agricultural Institute (IIMI), published its first Research water management in supporting broader Report entitled The new era of water resources development objectives such as increasing management: From "dry" to "wet" water savings. agricultural production, reducing agricultural The report stressed the increasingly difficult water use, raising farm-level incomes, and problems facing water management, including alleviating poverty and inequity. Yet, reliance growing demands for, and competition over, on a single-factor productivity metric, such scarce water resources, and the physical, as agricultural water productivity defined as economic and environmental constraints “crop per drop,” in multi-factor and multi-output to developing additional supplies. While a production processes can mask the complexity large body of research already existed on of agricultural systems as well as the trade- opportunities to improve irrigation efficiency offs required to achieve desired outcomes. The and water-use efficiency, David Seckler, the findings from this retrospective underscore the newly appointed Director General of IIMI at that limitations of single-factor productivity metrics time and author of the research report, argued while also highlighting opportunities to support that the classical notions of ‘efficiency’ may more comprehensive approaches to address be inappropriate for water management and water scarcity concerns and, ultimately, achieve planning at the basin level, as they do not take the broader development objectives. into account the potential reuse of water within A reflection on the lessons learned is larger hydrologic systems. To incorporate these especially relevant given the adoption of the reuse effects, Seckler proposed the concept of United Nations (UN) 2030 Agenda for Sustainable agricultural water productivity as an alternative Development in 2015 and their supporting metric to guide future basin management Sustainable Development Goals (SDGs). In strategies aimed at achieving real efficiency particular, Goal 6.4 aims to “by 2030, substantially gains and real water savings. increase water-use efficiency across all sectors Since the publication of that first Research and ensure sustainable withdrawals and supply Report, improving agricultural water productivity of freshwater to address water scarcity, and has been a core component of IWMI’s research substantially reduce the number of people agenda and a number of initiatives led by the suffering from water scarcity.” This is the first time Institute. This Research Report chronicles that the efficiency with which water is used has a the evolution of thinking on water productivity place on the mainstream development agenda. in the research agenda of IWMI and in the The insights and opportunities presented in this broader irrigation literature over the past 20 report are intended to inform the development and years. It describes the origins of the concept application of appropriate indicators and measures and the methodological developments, its to meaningfully track progress towards this stated operationalization through applied research, and goal, and support the UN’s broader objective of some lessons learned over the two decades achieving sustainable development for people, of research. This report further highlights planet and prosperity. vii Beyond “More Crop per Drop”: Evolving Thinking on Agricultural Water Productivity Meredith Giordano, Hugh Turral, Susanne M. Scheierling, David O. Tréguer and Peter G. McCornick 1. Introduction Improving agricultural water productivity has been These four programs have contributed a a core component of the International Water significant body of work on water productivity— Management Institute’s (IWMI’s) research agenda conceptually and operationally—addressing 1 since the mid-1990s. In 1996, David Seckler, the different geographies, scales and contexts. newly appointed Director General of IIMI at that Snapshots of this large body of work have been time, published the first IWMI Research Report, provided by a number of earlier reviews. A book The new era of water resources management: related to the CA program on the limits and From “dry” to “wet” water savings (Seckler opportunities for improving water productivity 1996). The report outlined several key ideas that in agriculture was an effort to collate the latest fundamentally changed IWMI’s research paradigm knowledge on concepts, methodologies, and case from one that focused on ‘irrigation efficiency’ studies globally (Kijne et al. 2003b). This was and ‘performance of irrigation systems’ to one followed by a book reviewing IWMI’s research centered on ‘water productivity’ and ‘river basin from 1996 to 2006 with a focus on the ‘more management’ (Rijsberman 2006). Since that time, crop per drop’ paradigm (Giordano et al. 2006). IWMI has contributed significantly to developing A synthesis of the CPWF described how the the concept of water productivity, particularly program’s research prompted a fundamental 2 as it relates to surface water and groundwater, shift in thinking from water productivity as a and supporting its application across a range of “principle objective” to water productivity as geographic and agroecological settings. an “entry point” to understand limitations to Water productivity has been central to many water access and availability (Vidal et al. 2014). IWMI research projects and to a number of Furthermore, Clement (2013) and Lautze et al. major programs led by the Institute, including the (2014) offered important insights on the concept Consultative Group on International Agricultural of water productivity and the extent to which the Research (CGIAR) System-Wide Initiative on Water concept is a true paradigm or, rather, an element Management (SWIM); Comprehensive Assessment of (or indicator within) the larger food-water- of Water Management in Agriculture (CA); CGIAR ecosystem discourse. Challenge Program on Water and Food (CPWF); Building on the earlier reviews, this report and the CGIAR Research Program on Water, Land synthesizes 20 years of research on water and Ecosystems (WLE). While IWMI’s view and productivity and lessons learned across the approach to the concept of water productivity has four major IWMI-led programs. It expands on a evolved through the research and experiences of background paper (IWMI 2015a) commissioned these programs, the concept has remained a core by The World Bank as part of a study carried component in each of them (Box 1). out by the Water and Agriculture Global Practices 1 IWMI was formally established as the International Irrigation Management Institute (IIMI) by an Act of the Parliament of Sri Lanka in 1985, and was officially recognized as the International Water Management Institute (IWMI) in 2000. 2 In this report, ‘water productivity’ refers to agricultural water productivity, unless otherwise stated. 1 Box 1. Major IWMI-led programs focused on water productivity. CGIAR System-Wide Initiative on Water Management (SWIM) (1995-1999): SWIM supported much of the early work on water productivity. Launched in 1995 by the Technical Advisory Committee of the CGIAR, SWIM was a collaborative research program focusing on broad issues of water management and agricultural production within a basin context. Key research themes included water accounting, salinity management, water-land relations, water productivity, multiple uses, water harvesting and basin-scale modeling. Many of the fundamental water productivity concepts, tools and indicators emerged from this body of work. Visit: http://www.iwmi.cgiar.org/publications/other-publication-types/swim-papers Comprehensive Assessment of Water Management in Agriculture (CA) (2001-2006): Commencement of the CA program in 2001 fostered a broader, multi-disciplinary body of conceptual and applied research on water—globally, regionally and in selected river basins in Asia and Africa. The program, involving hundreds of CGIAR researchers and partners, aimed to improve water investment and management decisions to meet poverty, hunger, and environmental sustainability objectives by understanding the (i) options to enhance agricultural water productivity; (ii) benefits, costs and impacts from past developments in irrigated agriculture; and (iii) water requirements to meet future food security and environmental sustainability goals. Visit: http://www.iwmi.cgiar.org/assessment/Publications/books.htm CGIAR Challenge Program on Water and Food (CPWF) (2004-2013): Informed by SWIM and early CA research, IWMI called for a major new research-for-development program to catalyze water productivity improvements that are effective and efficient as well as pro-poor, gender-equitable, and environmentally sustainable. This call led to the launch of the CPWF. The program was a major multi-partner program with the aim of raising water productivity and improving food security while helping to alleviate poverty, improve health, and attain environmental security. Over the course of a decade, the program funded over a hundred projects, concentrated primarily in 10 major river basins in Asia, Africa and South America. Visit: https://waterandfood.org CGIAR Research Program on Water, Land and Ecosystems (WLE) (2012-present): In 2011, the CPWF was reoriented to become part of the new CGIAR Research Program on Water, Land and Ecosystems (WLE). It comprises 11 CGIAR centers and the Food and Agriculture Organization of the United Nations (FAO) as core partners. Through collaboration with research, policy and implementing organizations in Asia, Africa and South America, WLE aims to increase water and land productivity in a sustainable manner in order to secure the provision of ecosystem services, improve food security, reduce poverty, and promote gender and social equity. Visit: https://wle.cgiar.org on Improving agricultural water productivity and offers a description of the pathways—with their beyond: what are the options? (Scheierling et al. associated interventions—for improving water 2014). This report aims to provide key highlights productivity, and discusses the contributions from two decades of IWMI research and the to broader development objectives. Based on broader irrigation literature on agricultural water these, and considering the broader literature, productivity, with an emphasis on the evolution Chapter 4 presents a set of key lessons and and application of the concept, highlighting its insights from two decades of research on water contributions and limitations while identifying productivity. Chapter 5 concludes by highlighting opportunities for further refinements in the way it how a focus on agricultural water productivity is understood and applied. Chapter 2 describes has brought greater attention to critical water the origins of the concept of agricultural water scarcity and management issues. Important productivity and its methodological developments. strategic opportunities remain, however, for Chapter 3 illustrates the different ways the concept continued improvements in technologies and has been operationalized in applied research, management practices, data sources, and 2 interdisciplinary research to develop and apply ensure sustainable withdrawals and supply more comprehensive approaches to address water of freshwater to address water scarcity, and scarcity concerns and, ultimately, make progress substantially reduce the number of people towards broader development objectives. suffering from water scarcity” (United Nations This reflection on past research, lessons 2015, 21). This is the first time the efficiency learned, and future opportunities to improve the with which water is used has a place on the understanding of the role of water in agricultural mainstream development agenda. We hope that production and productivity is timely given the some of the insights and opportunities presented adoption of the United Nations Sustainable in this report will also inform the development Development Goals (SDGs) in 2015. Specifically, and application of appropriate indicators and Goal 6.4 aims to, “by 2030, substantially increase measures to meaningfully track progress towards water-use efficiency across all sectors and the achievement of this goal. 2. Origins of the Concept and Methodological Developments IWMI’s focus on water productivity originated in methodological developments that supported its large part from a concern over increasing water operationalization. scarcity and longer-term trends in water supply and demand. Cautioning that the problems with water management may be much more severe 2.1 From Irrigation Efficiency to than commonly acknowledged, Seckler (1996, Agricultural Water Productivity 5) pointed out the “increasingly difficult problems facing water management,” including growing By the early 1990s, a wide body of research demands for, and competition over, scarce water from different disciplines—including agronomy, resources, as well as the physical, economic and plant physiology, and irrigation engineering— environmental constraints to developing additional already existed on opportunities to increase supplies. With agriculture being the largest user irrigation efficiency and water-use efficiency. Box of water resources worldwide, there was a need 2 presents some of the key terms and definitions. to identify ways to achieve real efficiency gains As a background to the definitions, it is useful and real water savings, and, thus, “opportunities to keep in mind the different measures of water for increasing the productivity of water” (Seckler quantity (Young 2005): 1996, 10). This idea was later formulated as ● Water withdrawal. This measure refers growing more food with the same or less amount to the amount of water removed (or of water, a concept that became popularly known 3 diverted) from a surface water or as ‘more crop per drop’. groundwater source. This chapter presents in more detail the evolution of the concept of agricultural water ● Water application . Water applied (or productivity, its influence on a “new era” of water delivered) differs from water withdrawn research at IWMI and elsewhere, and related by the amount of water lost in transit from 3 For example, in 2000, Kofi Annan, the then UN Secretary General referred to the need for a “‘Blue Revolution’ in agriculture, focused on increasing productivity per unit of water, or ‘more crop per drop’” (Annan 2000, 2). 3 the point of withdrawal to the point of use. to the amount of water that is actually This delivery (or conveyance) loss usually depleted by the crops, i.e., transferred stems from leakages (for example, from to the atmosphere through evaporation unlined earthen canals). from plant and soil surfaces and through ● Water consumption . This measure transpiration by plants, incorporated into (also called consumptive use, crop plant products, or otherwise removed from evapotranspiration, or depletion) refers the immediate water environment. Box 2. Terms and definitions. Classical irrigation efficiency The term refers to the ratio of water consumed by crops relative to water applied or, in some instances, relative to water withdrawn from a source. The numerator sometimes takes into account effective precipitation, by deducting it from the water consumed. To assess losses in the conveyance and application of irrigation water, the terms conveyance efficiency (ratio of water received at the farm gate relative to the water withdrawn from the water source) and application efficiency (ratio of water stored in the root zone and ultimately consumed by crops relative to the water delivered to the farm gate), respectively, are used. Sources: Israelsen 1932, 1950; Keller and Keller 1995; Burt et al. 1997; Cai et al. 2006; Jensen 2007. Water-use efficiency The term refers to the ratio of plant biomass (or yield) relative to the water consumed (or, in some instances, transpired). In the field of agronomy and plant physiology, it is typically expressed in kilograms per cubic meter 3 (kg/m ). Sources: Viets 1962; Molden 1997; Renault and Wallender 2000; Howell 2001; Hsiao et al. 2007; Perry et al. 2009. Effective irrigation efficiency The term is defined as the ratio of water consumed, minus effective precipitation, relative to the effective use of water. Effective use of water is the difference between water inflow to an irrigation system and water outflow (with both flows discounted for the leaching requirements to hold soil salinity at an acceptable level). The term was developed to address some of the limitations of classical irrigation efficiency by taking into account the quantity of water delivered from, and returned to, a water supply system (as well as the leaching requirements). Sources: Keller and Keller 1995; Keller et al. 1996; Cai et al. 2006; Jensen 2007. Water productivity The term refers to the ratio of physical production (in terms of biomass or crop yield) or, in some instances, ‘economic value’ of production (in terms of gross or net value of product) relative to water use (in terms of water 3 withdrawn, applied or consumed). It is, therefore, expressed in kilograms per cubic meter (kg/m ) or US dollars 3 per cubic meter (USD/m ). The selection of the numerator and denominator depends on the scale and focus of the analysis. Sources: Molden 1997; Molden et al. 1998b; Molden and Sakthivadivel 1999; Jensen 2007. 4 The different disciplines often understand the To demonstrate this point, Keller and Keller terms ‘efficiency’ and ‘productivity’ in different (1995) and Keller et al. (1996) used the case of ways, and also tend to focus on different the Nile Valley, where deep percolation either measures of water. For example, the classical returns to the river or recharges groundwater notion of irrigation efficiency was developed in supplies. Classical efficiency concepts do irrigation engineering, and commonly measures not account for such return flows and their the ratio of water consumed to water applied subsequent reuse. Thus, in this case, applying or withdrawn from a source. Plant physiologists irrigation efficiency concepts alone could lead and agronomists often use the term ‘water-use to the conclusion that significant opportunities efficiency’ and apply different definitions, such as existed for efficiency gains. In reality, however, the ratio of plant biomass or yield to transpiration, despite local irrigation inefficiencies, the scope 4 or the ratio of yield to water consumed. for improved efficiency at the sub-basin or basin A further confounding factor is the range of scales scale (and thus for real water savings) is limited (both spatial and temporal) at which the terms due to the reuse of the return flows elsewhere can be defined and applied, e.g., from field-scale, in the Nile Valley. Moreover, because of the seasonal measures of grain biomass per unit of opportunity to recharge groundwater aquifers water transpired to basin-scale, annual estimates through return flows, a strategy involving over- of the economic value obtained per unit of water watering on the fields and allowing seepage applied in the agriculture or other sectors (Kijne losses from conveyance canals may be preferable et al. 2003a; Bouman 2007; Molden et al. 2007b). to promoting local (application or conveyance) Starting in the mid-1990s, Seckler (1996) efficiency gains in this situation. and others (e.g., Keller and Keller 1995; Keller Several modifications were proposed to et al. 1996) argued that “efficiency” was a tricky address the limitations to classical efficiency concept in the context of a mobile resource such concepts. This includes the term ‘effective as water, and highlighted a need for metrics that irrigation efficiency’ to account for leaching account for the capture and reuse of water within requirements and return flows (Keller and broader hydrologic systems, such as river basins. Keller 1995), and the concept of ‘fractions As stated by Keller and Keller (1995, 7), “The of water use’ to break down consumptive classical concepts of irrigation efficiency have and non-consumptive uses and analyze been appropriate for farmers making irrigation the purposes for which water is consumed management decisions and for planners designing (Willardson et al. 1994; Frederiksen and irrigation conveyance and application systems. Perry 1995; Molden 1997). These refinements But applying classical efficiency concepts to water to the irrigation efficiency terminology, and basins as a whole leads to incorrect decisions the underlying principles, contributed to the 5 and, therefore, to faulty public policy.” conceptual development of water productivity. 4 Hsiao et al. (2007) showed that the ‘efficiency’ concept can be used for an array of steps that may be involved in converting an input into a final end product. They applied the chain of efficiency approach to systematically quantify and integrate the complex steps involved to convert water into an agricultural output. When the production of an output is complicated and an input (such as water) goes through a chain of sequential steps ending in the output, the overall efficiency of the process can be quantified in terms of the efficiency of each of the component steps. The output in any step in the chain is the input in the following step. For example, if water is withdrawn from a reservoir for irrigated crop production, the efficiency of the first step would be conveyance efficiency, calculated as the ratio of water received at the farm gate to the water withdrawn; the second step would be farm efficiency, calculated as the ratio of water at the field edge to the water at the farm gate, and so on. In all, the authors present a chain with three engineering-related and five agronomy-related efficiencies, with the last one being yield efficiency, defined as the ratio of harvested yield to the plant biomass. At each efficiency step, different interventions could be made to improve the respective efficiency measure, yet the effects would extend to the whole process. 5 It is interesting to note that the term ‘water productivity’ dates back, at least, to the nineteenth century, when it was used in connection with water management for agriculture in the Indus River Basin, and defined as the number of farm holdings per unit of available water (Renault and Wallender 2000). 5 Productivity is conventionally understood as a problems. The report aimed to inspire new and ratio that refers to output per unit of input. Water creative concepts that could address key food productivity , like land and labor productivity, security and environmental challenges—and is a single-factor productivity metric applied in thus initiated a “new era of water management” a multi-factor production process. In its basic (Seckler 1996, 3). The focus was on three form, water productivity measures production per fundamental points: unit of water use. The denominator, water use, ● C l a s s i c a l n o t i o n s o f i r r i g a t i o n may be measured in terms of water withdrawn, efficiency overlook the fact that so- applied, or consumed. The numerator can also called “losses” in water conveyance be expressed in different forms. In the case of and application may be reused, or physical water productivity, expressed in kilograms “recycled”, elsewhere in a river basin. 6 3 per cubic meter (kg/m ), the numerator is defined Thus, measures of irrigation efficiency as the physical mass of production (such as do not take into account the recycling biomass or crop yield). In the case of economic opportunities for irrigation water. water productivity, expressed in US dollars 3 per cubic meter (USD/m ), the numerator is ● Because of these recycling opportunities, usually expressed as gross value of output (yield there is the need to distinguish between multiplied by price). Other formulations for the real water savings (e.g., due to a numerator have also been used in the literature; reduction in consumptive water use) an example is water productivity in nutritional and reallocation of water (e.g., where terms, expressed in protein grams or kilocalories water is redistributed from one user to 3 (kcal/m ) (Molden 1997; Molden and Sakthivadivel another). Because of the extent of water 1999; Renault and Wallender 2000). The water recycling at the basin scale, the actual productivity concept is thus applied for different scope for real water savings is often less purposes and at a range of scales (field, farm, than imagined. For example, a water irrigation system, and basin). conservation strategy that simply reduces The next section describes how the evolution the amount of drainage water that would and development of the water productivity otherwise be reused downstream does concept inspired a “new era” of water research at not result in real water savings. By IWMI. This included a shift from an earlier focus contrast, if the excess drainage water on farm- and irrigation system-level irrigation would have otherwise flowed into saline efficiency to one focused on ways to grow more shallow groundwater, real water savings food with the same or less amount of water—with are possible. the aim of alleviating water scarcity, achieving ● When considering water productivity or, more food security and placing less strain on the generally, water management strategies, environment (Rijsberman and Molden 2001). context is important. If a basin is closing or closed (i.e., no usable water leaves the basin), identifying opportunities to increase 2.2 A “New Era of Water Resources water productivity becomes increasingly Management” important. By contrast, in an open basin (i.e., a basin with uncommitted utilizable outflows), IWMI Research Report 1 (Seckler 1996) other water management objectives may introduced the concept of water productivity and be more appropriate—such as increasing related strategies for its improvement to promote the supply of water to a particular sector, “real solutions” to complex water management transferring water to another basin with more 6 Seckler later referred to this as the “water multiplier effect”, which can enhance the productivity of the water inflow into a basin (Seckler et al. 2003). 6 pressing water needs, or reserving water for framework, illustrated in Figure 1, is based on a environmental services. water balance approach and a categorization of water based on how it is (re)used (Molden 1997; Taking the above points into consideration, Molden et al. 1998a; Molden and Sakthivadivel Seckler (1996) highlighted four basic basin- 1999; Jensen 2007; Perry 2007): scale water management strategies to promote improved water productivity and achieve real ● Inflow into the domain of interest is efficiency gains in both open and closed basins: classified as gross inflow (i.e., the amount of water flowing into a sub-basin from (i) Increase the output per unit of evaporated precipitation and surface and subsurface water. sources) and net inflow (i.e., gross inflow (ii) Reduce losses of water to sinks and plus any changes in storage). evaporation. ● Available water is the net inflow less the (iii) Reduce the deterioration of water quality. amount of water set aside for committed (iv) Switch from lower-value to higher-value outflows (such as for downstream water uses of water. rights and non-utilizable outflows), and includes depleted water (i.e., water Seckler described the potential for increasing withdrawn that is unavailable for further water productivity and efficiency from water use use) and uncommitted utilizable outflows. as enormous, but also highlighted the equally enormous conceptual and practical challenges in ● Depleted water includes: doing so, a challenge which he encouraged IWMI ○ Beneficial depletion, such as (i) and others to overcome. process depletion (i.e., for an intended process; for example, in agriculture, the water transpired by crops plus 2.3 Water Accounting and Water the amount incorporated into plant Productivity Indicators tissues); and (ii) non-process depletion (i.e., for a process other than the In the years following the publication of IWMI one for which the diversion was Research Report 1 (Seckler 1996), the Institute’s intended; for example, the water research concentrated on developing a common transpired by trees along an irrigation framework and set of indicators to assess and canal); and measure water productivity across a range of uses and scales. The SWIM and CA programs ○ Non-beneficial depletion (such as were a fundamental part of this effort, laying the water flows to sinks). foundation for the concept’s operationalization. Below is a summary of some of the key ● Outflow from the domain comprises: developments in this regard. ○ Uncommitted outflows, both utilizable and non-utilizable (i.e., water that 2.3.1 Water Accounting and Performance is not depleted and in excess of Indicators requirements or storage or operational To place water productivity in context, the first capacity); and SWIM Paper focused on the development of a ○ C o m m i t t e d o u t f l o w s f o r o t h e r water accounting framework to identify possible purposes downstream (e.g., strategies to achieve real water savings and downstream water rights, minimum improve water productivity (Molden 1997). The streamflows, offshore fisheries). 7 FIGURE 1. Water accounting framework. s ces Pro Beneficial ss Gross inflow pr oce on- Depleted N Net inflow Available cial b enefi Non- INFLOW Utilizable Surface and subsurface Uncommitted flows, precipitation Non-utiliza ble Outflow Co mm itte d Removal from Addition to Storage Source: Adapted from Molden et al. 2003. The water accounting framework was means to generalize about water productivity developed as a means to demonstrate and use across scales—such as the crop, field, how much water is actually depleted in a farm, irrigation system or the basin level— given domain, where and for what purpose, depending on the purpose and users of the compared to what is available. It provides a analysis (Table 1). TABLE 1. Water productivity at different scales. Scale Crop Field Farm Irrigation system Basin Purpose Assessing Assessing Assessing Assessing irrigation Assessing water energy biomass or harvestable yield system allocation, conversion, harvestable or economic performance in including use of biomass or yield from a return from a terms of harvestable water in harvestable particular farm’s crop yield or economic agriculture as yield from a cropping production return compared to particular crop system other sectors or cultivar Users Plant Soil and crop Agriculturalists, Irrigation engineers, Water physiologists, scientists, farmers water managers managers, farmers farmers hydrologists Sources: Adapted from Molden 1997; Molden et al. 2003, 2007b; Cook et al. 2006. 8 The aim of the water accounting framework ● Productivity of Water (PW) is the physical was to provide first-order estimates of water use mass of production (or the economic value within and across crops (or sectors), as well as of production) per unit of water in terms of insights into opportunities for real water savings net inflow, gross inflow, depletion, process and improvements in water productivity. Some depletion, or available water: of the advantages of the framework include its ability to: PWnet = productivity (kg or USD)/ • identify total water depletions (beneficial net inflow and non-beneficial), PWgross = productivity (kg or USD)/ • distinguish between process (e.g., gross inflow agriculture, cities, and industry) and PWdepleted = productivity (kg or non-process (e.g., forests, grassland and USD)/depletion water bodies) beneficial depletions, • estimate the components of beneficial and PWprocess = productivity (kg or non-beneficial depletions, and USD)/process depletion • account for downstream commitments. PWavailable = productivity (kg or To complement the framework, IWMI USD)/available water introduced a set of performance indicators to characterize the various uses of water in a given For more complex comparisons across domain (Molden 1997; Molden et al. 1998a). multiple crops and multiple countries, an These indicators built on the notions of effective approach to standardize water productivity irrigation efficiency and fractions of water use measures was proposed. This involved the (Willardson et al. 1994; Frederiksen and Perry conversion of physical output to value of output 1995), described earlier, and were organized into through the use of a standardized gross value three main groups as follows: of production indicator (Molden et al. 1998b; Sakthivadivel et al. 1999). Where data were ● Depleted Fraction (DF) is the proportion available, the indicator could also be used for of process and non-process depletion other agricultural products besides crops, such in relation to net inflow, gross inflow or as fish and livestock (Cook et al. 2006). available water: IWMI applied the water accounting DFnet = depletion/net inflow framework and the related indicators in a variety of locations at different scales to DFgross = depletion/gross inflow understand current conditions and opportunities DFavailable = depletion/available water to achieve water savings and increase water ● Process Fraction (PF) is the proportion productivity in irrigated agriculture. An example of process depletion in relation to inflow, of the water accounting framework applied to total depletion or available water: 7 the Nile River below the High Aswan Dam, drawing from water balance studies carried PFnet = process depletion/net inflow out between 1993 and 1994, is provided below PFgross = process depletion/ (Figure 2 and Table 2). gross inflow This example illustrates a case where PFdepleted = process depletion/total a large proportion of depleted water depletion (84%) is used for intended (“process”) PFavailable = process depletion/ purposes, including crop production, and available water municipal, industrial and navigational uses. 7 The process fraction of depleted water is similar to the concept of effective irrigation efficiency. 9 FIGURE 2. Water accounting framework for the Nile River below the High Aswan Dam (1993-1994). PROCESS DEPLETION Crop ET = 36.8 km3 AVAILABLE = DEPLETED (48.2 km3) Municipal, industrial and navigation=3.5 km3 Aswan Dam releases = 55.2 km3 NON-PROCESS Rain = 1.0 km3 Evaporative depletion and non-bene cial drainage = 8.0 km3 Committed for environment 8.0 km3 Source: Based on Molden and Sakthivadivel 1999. Note: ET = Evapotranspiration. TABLE 2. Water accounting components for the Nile River below the High Aswan Dam (1993-1994). Indicator Components Indicator value Depleted Fraction 1 3 3 DFnet = DFgross 48.2 km /(55.2 + 1.0) km 86% 3 3 DFavailable 48.2 km /48.2 km 100% Process Fraction (all uses) 3 3 PFdepleted (36.8 + 3.5) km /48.2 km 84% 3 3 PFavailable (36.8 + 3.5) km /48.2 km 84% Process Fraction (irrigated agriculture) 2 3 3 PFavailable 36.8 km /(55.2 + 1.0 - 8.0 - 3.5) km 82% 3 Productivity of Water 3 3 PWgross USD 7.5 billion/56.2 km USD 0.13/m 3 3 PWdepleted USD 7.5 billion/48.2 km USD 0.15/m 3 3 PWprocess USD 7.5 billion/36.8 km USD 0.20/m Sources: Adapted from Molden et al. 1998a; Molden and Sakthivadivel 1999. Notes: 1 Assumes no change in storage, therefore gross inflow equals net inflow. 2 Water available for irrigation equals total water available less committed water (for the environment, and municipal, industrial, and navigational uses). 3 Assumes gross value of production (in 1993 USD) equals USD 7.5 billion. 10 In this case, converting the non-beneficial portion and benefits of water at various levels, and of the remaining non-process depletion (e.g., non- how these values may vary significantly across beneficial drainage that is in excess of environmental time, space and user (Hussain et al. 2007). As requirements) could allow for improvements in the described by Bakker et al. (1999, vii), “to ensure productivity of water (Molden et al. 1998a). efficient, equitable, and sustainable water use, Similar studies were carried out at irrigation to reduce poverty and improve the well-being of system and basin scales in Sri Lanka (Molden et the community, irrigation and water resources al. 1998b; Molden and Sakthivadivel 1999), India policies need to take into account all uses and (Elkaduwa and Sakthivadivel 1999; Bastiaanssen users of water within the irrigation system.” et al. 1999a, 1999b; Hussain et al. 2000, 2003), Moreover, even while many argued that Pakistan (Hussain et al. 2000; Tahir and Habib improving water productivity was an inherently 2000), China (IWMI 2003; Roost 2003), Turkey good idea, IWMI researchers cautioned early on (Kite and Droogers 2000a; IWMI and GDRS that a focus on a single-factor productivity metric 2000), Iran (Murray-Rust and Droogers 2004), and in agricultural production processes with multiple Central Asia (Murray-Rust et al. 2003). factors (or inputs) may provide misleading results from the perspective of the farmer, as well as from the economy as a whole (Barker et al. 2003). An 2.3.2 Beyond “More Crop per Drop” example would be researchers and extension agents Early reflections on water productivity and the who focus on potential water productivity gains (either related indicators highlighted several limitations in physical or “economic” terms) without considering to a restrictive “crop per drop” interpretation and the often significant, additional costs involved. Yet, the need for methodological advances to assess improvements in agricultural water productivity may the broader implications from, including the costs require more labor, better management, or other and benefits of, improved water productivity. additional inputs, and the changes in these inputs and Restricting the interpretation and application of the related costs and benefits (economic, financial, water productivity to crop outputs, for example, social and environmental) tend not to be incorporated ignored important non-crop outputs such as into single-factor productivity metrics. A greater fisheries, livestock, environmental services and understanding of these broader costs and benefits other benefits (and costs) from the use and would be needed to inform policy and investment reuse of water (Rijsberman 2006). In some advice for enhancing water productivity to address circumstances, non-process uses (such as food security, environmental sustainability and poverty environmental services) may provide as much alleviation objectives (Barker et al. 2003; Kijne 2003). value or more than the process uses (Renault and Since the early 2000s, these reflections Wallender 2000; Murray-Rust and Turral 2006). prompted IWMI and others to broaden the Several studies conducted by the SWIM and definition of agricultural water productivity and CA programs further aimed to identify and, as related metrics to include a wider perspective far as possible, quantify the range of benefits on water use—such as crop and non-crop and (both process and non-process) from the use other livelihood and ecological benefits and costs (and non-use) of water (e.g., Bakker et al. 1999; from improving water productivity. IWMI argued Bakker and Matsuno 2001; Meinzen-Dick and that water productivity must be understood in Bakker 1999, 2001; Renwick 2001; Meinzen-Dick the “widest possible sense” with the ultimate and van der Hoek 2001; Hussain et al. 2007; objective of increasing yields, fisheries, ecosystem Molden et al. 2007b). These studies highlighted services and direct social benefits at less cost that conventional “crop per drop” indicators of (social, ecological) per unit of water consumed water productivity may not provide reasonable (Rijsberman 2006; Molden et al. 2010). A review estimates of the overall benefits or value of of some of the applied research on agricultural water as they do not account for the broader water productivity further demonstrates this uses as well as the direct and indirect costs evolving thinking by IWMI and its partners. 11 3. Applied Research Since the launch of the SWIM program in 1995, Although the performance indicators had IWMI and its partners have carried out numerous intentionally been kept simple, the availability case studies applying the concept of water of primary data and the related cost and time productivity and the related tools described above. challenges as well as methodological constraints These case studies differed in scale and context often hampered their application in field-based (such as agroecosystem, and socioeconomic studies (Sakthivadivel et al. 1999; Murray- and institutional setting), and applied different Rust and Turral 2006). Even more problems approaches, including advanced modeling were encountered at the scale of the irrigation and remote sensing methods, to address system or the basin. To ease these constraints, data constraints. Many of the case studies IWMI tested the use of integrated crop and were initiated by the four IWMI-led programs hydrologic modeling—later in combination with (SWIM, CA, CPWF and WLE), and included remote sensing tools—to simulate the process global analyses as well as regional (basin- and of water flows and measure water productivity irrigation system-level) assessments in South and in its various forms and at various scales (e.g., Southeast Asia, sub-Saharan Africa, North Africa Kite and Droogers 2000b; Droogers and Kite and Central Asia, and Central and South America. 2001a, 2001b; Ines et al. 2002; Aerts and Over the last 20 years, this body of research has Droogers 2004). Modeling allowed researchers to generated over 300 reports and publications. In extrapolate and generate scenarios to complement this chapter, some of the research studies and data derived from field studies. findings are highlighted under three thematic An example is the study in the Gediz Basin, areas: water productivity analysis and mapping; Turkey, where researchers applied the Soil- pathways to increase water productivity; and water Water-Atmosphere-Plant (SWAP) model for the productivity and broader development objectives. analysis at the field and irrigation system scale, combined with the Semi-Distributed Land Use- Based Runoff Processes (SLURP) model for the 3.1 Water Productivity Analysis and analysis at basin scale, to estimate the water Mapping balance and calculate different water productivity indicators in physical terms (Droogers and Kite The water accounting methodology and related 2001a). Table 3 illustrates yields and the resultant performance indicators described in section water productivity indicators at mid-basin and 2.3.1 provided an overarching framework to tail-end fields, and at the irrigation system and assess water inflows, uses and outflows across basin scales. The fields located further upstream different spatial scales, and helped to overcome performed better in terms of yield and water some of the limitations of the classical irrigation productivity indicators than those at the tail end— efficiency concepts by incorporating other uses in part due to its location but also due to different besides crop water uses and making more climate conditions. Yield and water productivity explicit the interactions between different uses, indicators at the basin scale were considerably including agricultural and non-agricultural uses. lower than at the field and irrigation system scales The methodology allowed for an analysis of total because of large areas in the basin with other water depletion—for beneficial and non-beneficial ‘less-productive’ land cover. purposes—to assess strategies to improve water In other studies, models were developed, productivity, identify opportunities for real water calibrated, and then applied to assess the savings, and assess the net benefits (in terms of effect of various inputs on yield, productivity changes in the water productivity indicators) from and the water balance, with the aim of water reallocation (Murray-Rust and Turral 2006). supporting resource allocation and policy 12 TABLE 3. Water productivity indicators in the Gediz Basin, Turkey (averaged over the nine-year period [1989-1997]). 3 3 3 Scale Yield (kg/ha)* PWinflow (kg/m ) PWdepleted (kg/m ) PWprocess (kg/m ) Field (mid-basin) 2,800 0.30 0.39 0.54 Field (tail end) 2,289 0.24 0.24 0.38 Irrigation system 2,614 0.30 0.32 0.40 Basin 874 0.16 0.16 0.21 Source: Droogers and Kite 2001a. * Notes: Yield is the simulated yield for cotton at field scale, for irrigated crops at the irrigation system scale, and for agricultural and non- agricultural production at the basin scale. 3 PWinflow = yield/net inflow, PWdepleted = yield/depletion, and PWprocess = yield/process depletion, all expressed in kg (yield) per m (water). decisions at higher scales (Murray-Rust and (Cai and Rosegrant 2003). Figure 3 presents Turral 2006). As part of the CA program, water productivity estimates for irrigated rice for example, the IMPACT-WATER model (as ratios of yield relative to water consumed) (combining the International Model for Policy for developing and developed countries, and Analysis of Agricultural Commodities and Trade for the world, based on the IMPACT-WATER [IMPACT] model with a water simulation model) model. Estimates indicate that developed was used for the analysis of various water countries have higher water productivity values productivity scenarios for irrigated rice globally than developing countries and the world. and regionally; and for projections taking into However, the values converge over time due to account possible impacts from technology and a projected higher rate of increase in irrigated management improvements, investments in yield and increase in water-use efficiency for agricultural infrastructure and research, and irrigated crops in developing countries during increased environmental flow requirements the period under analysis. FIGURE 3. Water productivity estimates for irrigated rice (1995-2025). Irrigated rice (developed countries) Irrigated rice (developing countries) 0.7 Irrigated rice (world) Water productivity (kg m-3) 0.6 0.5 0.4 0.3 1996 2000 2004 2008 2012 2016 2020 2024 Year Source: Cai and Rosegrant 2003. 13 In many cases, the availability of data for irrigation performance variability and, based on that, modeling purposes, particularly at different spatial identify opportunities to improve overall performance and temporal scales, continued to be an issue (Ahmad et al. 2009). The values for land productivity (Droogers and Kite 2001a). The coupling of remote were calculated as the gross value of production sensing with integrated (crop-hydrologic) modeling per hectare, and water productivity values were helped to overcome some of these challenges. calculated as the gross value of production per unit Remote sensing provided important additional data of consumptive use (actual evapotranspiration)—for inputs, such as estimates on land use and water summer and winter cropping seasons as well as consumption, and supported model calibration annually. Figure 4 shows the spatial variation in (Karimi 2014). From the early 2000s, IWMI annual values for actual evapotranspiration, gross placed significant emphasis on the development value of production, and land and water productivity and application of remote sensing technologies in the basin. Among the reasons for the differences combined with crop and hydrologic modeling tools across the basin are the quality and reliability of to map and assess water productivity and simulate surface water and groundwater supplies, and farmers’ scenarios at multiple scales. crop choices. The study demonstrated how remote In the Rechna Doab Basin in Pakistan, for sensing-based estimates of water consumption example, the Surface Energy Balance Algorithm for combined with secondary agricultural production data Land (SEBAL) model (Bastiaanssen et al. 1998a, can provide estimates of land and water productivity, 1998b) was combined with secondary agricultural and indicate opportunities for improving water production data to estimate water productivity, assess productivity at different spatial and temporal scales. FIGURE 4. Spatial variation in annual values for actual evapotranspiration, gross value of production, and land and water productivity in the Rechna Doab Basin, Pakistan (May 2001-May 2002). Source: Ahmad et al. 2009. Notes: Eta = Actual evapotranspiration; GVP = gross value of production; WP = water productivity. 14 Not only did remote sensing techniques Karimi and Bastiaanssen 2015; Karimi et al. 2015). help to fill data gaps, but they also contributed For example, a recent study on the combination of to further developments in the water accounting remote sensing and water accounting found that, framework. The recently developed Water while the majority of estimates of WA+ parameters Accounting Plus (WA+) framework uses remote and indicators have a coefficient of variation of less sensing to incorporate more details in the than 20% (an accuracy that is on par with field processes of water use and the mechanisms to measures), some uncertainty remains with regard achieve water productivity improvements (Karimi to the estimates of overall basin depletion and et al. 2012, 2013a). WA+ uses satellite-derived groundwater flows (Karimi and Bastiaanssen 2015; estimates of land use, rainfall, evaporation, Karimi et al. 2015). transpiration, interception, water levels of open Even with these technological advances, water bodies, biomass production, crop yield IWMI researchers have emphasized that and measured basin outflow to produce a water water productivity measures on their own do account. These data are supplemented with the not necessarily provide sufficient information to outputs of global hydrological models on surface determine whether improving water productivity water networks and aquifers. The use of the WA+ is desirable and if so, what specific actions need framework allows the following: to be taken (Lautze et al. 2014; Wichelns 2014a, 2014b). This requires an understanding of different ● Link land use and evapotranspiration to intervention pathways, the context in which assess the impact of land-use change on the pathways are introduced, and their related exploitable water resources. production, livelihood and ecological benefits and ● Distinguish between managed and costs—as further elaborated in the next section. manageable depletions in a basin (i.e., depletions defined as evapotranspiration processes that are or could be 3.2 Pathways to Increase Water manipulated by land use, cultivation Productivity practices and water use) and non- manageable depletions. Building on the four basic, basin-scale water management strategies (Seckler 1996) discussed ● Differentiate between surface water in section 2.2 and the water accounting framework and groundwater systems to consider presented in section 2.3.1, four main pathways different management options and legal with different interventions for increasing water regulations. productivity at the irrigation system or basin level ● Estimate changes in evapotranspiration were identified by the 2000s (Molden et al. 2001a, (difference between withdrawals and 2003, 2007b): return flows) for different land-use (i) Increase yield per unit of water consumed by, categories and water user groups to for example: assign benefits and costs from changes in managed water depletion. ● improving water management by providing better timing of water supplies to reduce Over the past 20 years, advances in mapping, stress at critical crop growth stages or modeling and remote sensing techniques have by increasing the reliability of supplies to eased some of the challenges in assessing water enable farmers to invest more in other productivity and its variation in different contexts, agricultural inputs; and have also contributed to a better framework for water accounting. Technical and methodological ● improving non-water inputs that increase challenges remain, however, in the accuracy and production per unit of water consumed interpretation of water productivity and accounting and agronomic practices, such as laser measures (Molden et al. 2010; Cai et al. 2011; land leveling and fertilization; and 15 ● changing to new or different crop varieties ● reallocating water from lower- to higher- with higher yield per unit of water value uses within or between sectors, consumed. while addressing possible effects on downstream uses. (ii) Reduce non-beneficial depletion by, for example: While not emphasized in the earlier literature, it should be noted that the different pathways ● increasing the proportion of water applied implicitly target different formulations of water that is used beneficially by crops, by (a) productivity: the first pathway focuses on reducing evaporation from water applied achieving more yield per unit of water consumed, to irrigated fields through more capital- and the fourth pathway is about improving water intensive technologies (such as drip productivity expressed in “economic” terms (US irrigation) or better agronomic practices 3 dollars per cubic meter [USD/m ]). The second (such as mulching or changing crop and third pathways aim to increase the amount of planting dates to match periods of less water available for beneficial use. evaporative demand); and (b) restricting The sections below present key research evaporation from bare soil through highlights addressing each of the four pathways, conservation agriculture (such as land and the related interventions and water leveling or zero tillage); productivity indicators. As will be seen, however, ● lessening evapotranspiration from fallow many studies incorporated elements from more land by reducing the area of free water than one pathway to increase water productivity. surfaces, decreasing non-beneficial or less- beneficial vegetation, and controlling weeds; 3.2.1 Increase Yield per Unit of Water Consumed ● reducing water flows to sinks by decreasing irrecoverable deep percolation IWMI and its partners have assessed a number of and surface runoff, by such measures as water-related interventions to increase crop yield canal lining and precision irrigation; per unit of water consumed. A frequent focus was on improving the timing of water supplies using ● minimizing salinization (or pollution) of supplemental irrigation or deficit irrigation. In dry recoverable return flows, by minimizing regions, moisture availability, especially during flows through saline (or polluted) soils and critical periods, is frequently the most significant groundwater; and factor limiting agricultural production. Research ● shunting polluted water to sinks to avoid carried out through the SWIM, CA and subsequent the need for dilution with water of usable programs explored the extent to which supplemental quality. irrigation, often coupled with rainwater harvesting, (iii) Tap uncommitted flows by, for example: can enhance yields as well as water productivity in arid and semi-arid regions (e.g., Oweis et al. 1999; ● adding water storage facilities, including Wani et al. 2009; Hessari et al. 2012). reservoirs, groundwater aquifers, tanks Several longer-term studies, conducted at and ponds, on farmers’ fields; experimental sites of the International Center for ● improving management of existing Agricultural Research in the Dry Areas (ICARDA) facilities to obtain more beneficial use of in northern Syria, found that rainfall supplemented existing water supplies; and by irrigation increases water productivity in wheat systems. Supplemental irrigation contributed to ● reusing uncommitted return flows through the alleviation of moisture stress during the most gravity or pump diversions to increase sensitive stages of crop growth and thus to an irrigated area. increase in yield per unit of water consumed (or (iv) Reallocate water among uses by, for example: evapotranspiration) (Oweis et al. 1999; Zhang and 16 Oweis 1999; Oweis and Hachum 2003). Table 4 (compared to rainfed conditions) and also led to shows the results of a study where mean water an increase in water productivity from 0.53 to 1.85 3 productivity of bread-wheat grains, measured kg/m ET. With full irrigation, water productivity 3 over 5 years (1991-1996), increased from 0.96 to was 0.70 kg/m ET (Oweis and Hachum 2003; 3 1.11 kg/m as a result of supplemental irrigation. Zhang and Oweis 1999). Supplemental irrigation on its own would have While these cases illustrate the potential for been insufficient to support crop production. water productivity improvements, it is not clear However, when combined with rainfall, it led to if productivity gains in the form of increased an increase in water productivity in most years, yield per ET at the field or irrigation system level particularly in the drier years. The study also translate to improved productivity at sub-basin shows that when rainfall is ignored and only or basin scale. Cost and risk considerations irrigation water is considered, water productivity would also need to be taken into account. estimates are significantly higher. Deficit irrigation, for example, requires precise Similar increases in water productivity for the management in terms of scheduling water and combination of rainfall and irrigation water were other inputs, information on rainfall amounts documented in Burkina Faso and Kenya, where and distribution, and specialized agronomic supplemental irrigation was applied to rainfed knowledge on crop water use and crop response crops (Rockström et al. 2003; Rockström and to factors such as water deficits, planting Barron 2007). dates and nitrogen application (Oweis and Deficit irrigation is another practice that Hachum 2003). The costs, risks, and overall can increase yield per unit of water consumed. net benefits would need to be assessed before Using this technique, crops are deliberately recommending the adoption of such practices exposed to water stress (mostly through reduced to farmers for the purpose of improving water irrigation water applications in non-critical periods) productivity (Kijne 2003). resulting in some yield reductions. With well- timed applications, consumptive water use can 3.2.2 Reduce Non-Beneficial Depletion be reduced more than yield, resulting in water productivity increases. In field trials with wheat Reducing non-beneficial depletion involves carried out by ICARDA in semi-arid northern reducing “waste” and generating real water Syria from 1994 to 2000, supplemental irrigation savings (Molden et al. 2003). Two key areas of combined with deficit irrigation improved yields research have focused on the introduction of: TABLE 4. Rainwater productivity (WPR), combined rainfall and irrigation water productivity (WPR+I), and irrigation water productivity (WPI) for bread-wheat grains in northern Syria (1991-1996). Year Rainfall (R) WPR Supplemental WPR+I WPI 3 3 3 (mm) (kg/m ET) irrigation (I) (kg/m ET) (kg/m ET) (mm) 1991-1992 351 1.04 165 1.16 1.46 1992-1993 287 0.70 203 1.23 2.12 1993-1994 358 1.08 175 1.17 1.43 1994-1995 318 1.09 238 1.08 1.06 1995-1996 395 0.91 100 0.90 0.73 Mean WP 0.96 1.11 1.36 Source: Oweis and Hachum 2003. Notes: WP = Water productivity; ET = evapotranspiration. 17 ● capital-intensive technologies, such as use of key inputs at the field scale as a result of sprinkler, drip and other micro-irrigation the introduction of laser leveling and zero tillage technologies (e.g., Sally et al. 2000; technologies. The reductions in water application Rockström et al. 2003; Indu et al. 2008; amounted to approximately 24% and 32% for Kumar et al. 2009; Namara et al. 2005, laser leveling and zero tillage, respectively. 2007); and As Ahmad et al. (2014) pointed out, whether the reduced water applications translate into ● agronomic practices, including land reduced water consumption and real water leveling and zero tillage (e.g., Ahmad savings at the larger scales depends on the et al. 2006, 2007a, 2007b, 2014), and water balance in a given setting and the broader alternate wet and dry irrigation of rice hydrologic system, and the adjustments farmers (Dong et al. 2004; Loeve et al. 2002, make in response to the “saved” water. In the 2004a, 2004b). case of the Rechna Doab Basin, the increased While many studies identified a potential profitability following the adoption of the to reduce non-beneficial depletion, a recurrent technologies allowed many farmers—in particular, recommendation has also been the need to medium- and large-scale farmers with better consider context, scale and hydrology in the access to land and the necessary machinery—to interpretation and potential application of the expand the cultivated area or increase cropping results. It is often assumed, for example, that intensity. Table 5 shows the estimated increase micro-irrigation technologies will result in less in annual crop evapotranspiration (consumptive evapotranspiration (or consumptive water use) water use) at each of the different farm sizes, with than surface irrigation. This is not necessarily a more significant change in the winter dry (Rabi) the case. Rather, the outcome depends on the season than in the summer monsoon ( Kharif) context (both biophysical and institutional), as season based on the monsoon. well as the specific technologies or agronomic In fresh groundwater areas, farmers practices applied and how they are managed improved application efficiency of (regulated) (Seckler 1999; Molden et al. 2001b, 2007b; Kendy canal water and, at the same time, increased et al. 2003; Kijne 2003). (unregulated) groundwater abstraction from the Research conducted by the CA program region’s permeable aquifer. The study estimated in the rice-wheat zone of Pakistan’s Indus that overall water consumption at the system Basin illustrates this point. Ahmad et al. (2006, scale increased by 59 million cubic meters 3 2007a, 2007b, 2014) examined the impact of (Mm )/year following the adoption of “resource two “resource conservation” technologies (laser conservation” technologies. Thus, improvements leveling of fields and zero tillage) on water in field-scale water productivity (in terms of water application, water productivity, and real water application) did not result in reduced water use savings. The study, carried out in the Rechna (in terms of consumptive use) at the farm or Doab Basin in the semi-arid Punjab Province, larger scales. Ahmad et al. (2014) stressed involved a survey of 223 small-, medium- and that, in different contexts (e.g., where additional large-scale farmers, field measurements, and land cannot be brought under irrigation, highly remote sensing to assess the factors influencing saline groundwater conditions limit groundwater the adoption of the technologies in rice-wheat recycling, or institutional arrangements restrict cropping systems, and the impacts on water additional water applications), the outcome use and “savings” at field, farm and irrigation could be different, further highlighting the range system level. of factors that can influence the outcomes from According to the study, the main factors water productivity interventions. influencing farmers’ adoption of each of the In this case, the introduction of “resource technologies were increased yields and reduced conservation” technologies reduced input costs. Figure 5 shows the changes in the water applications at the farm scale. 18 FIGURE 5. Impacts of laser leveling and zero tillage technologies on field-scale water application and the use of other inputs as reported by farmers surveyed in the Rechna Doab Basin, Pakistan (2004). 20 Laser leveling 10 Zero tillage 5 Percentage change at eld level (%) 0 -2 -2 -2 -10 -14 -20 -16 -24 -30 -32 -40 -50 -52 -52 -60 Water Fuel Labor Fertilizer Herbicide Basic inputs Source: Ahmad et al. 2014. Note: Data for zero tillage and laser leveling refer to wheat and the mean of various crops, respectively. TABLE 5. Change in crop evapotranspiration as a result of the adoption of “resource conservation” technologies in the Rechna Doab Basin, Pakistan (2004). Average farm size under hange in potential crop evapotranspiration (%) C each category (ha) Rabi Kharif Annual 2.83 (small) 1.5 -1.1 0.2 7.69 (medium) 5.0 3.7 5.0 33.18 (large) 7.7 5.0 8.1 Source: Ahmad et al. 2014. Note: The data represent the combined impact of adopting zero tillage (for wheat cultivation in the Rabi season) and laser leveling for various crops (in the Rabi and Kharif seasons). However, improved water productivity (in in terms of increased cropping intensity, the terms of yield and income per unit of water medium- and large-scale farmers received a applied) encouraged farmers, who had access disproportionate share of the benefits by being to fallow land (generally medium- and large- able to expand their irrigated area. This is not to scale farmers), to expand their irrigated area. say that improving productivity necessarily further Conversely, smallholder farmers, in general, increases inequity, but it is important to consider had little additional land for expansion. While the potential for differential outcomes across all farmers benefitted from the intervention different socioeconomic groupings. 19 3.2.3 Tap Uncommitted Flows carbon emissions. An example of this draws from IWMI’s research on groundwater use and In many locations, additional storage of water management in China, conducted in Luangcheng above or below ground is key to accessing County of Hebei Province (Kendy et al. 2003). uncommitted flows. Section 3.2.1 discussed water The North China Plain has traditionally been a productivity gains that may result from access key agricultural production center and a critical to additional surface storage (such as rainwater region to help achieve the country’s food security harvesting) for supplemental irrigation. Access goals. To support the increase in agricultural to groundwater in aquifers is another pathway to production, groundwater has been used as tapping uncommitted flows or reusing return flows. the primary source of irrigation water since Since the 1950s, with the advent of the modern the 1960s—mainly to supplement the region’s pump and tube wells, groundwater irrigation has unpredictable rainfall patterns. In Luangcheng increased dramatically (Shah 2014). County, a growing industrial sector coupled Research suggests that—at least in terms of with the local government’s focus on expanding water applied—irrigation with groundwater may be wheat production led to increasing competition for more productive than irrigation with surface water, groundwater supplies. In response, the agriculture both in terms of physical and “economic” water sector moved toward improving irrigation efficiency productivity. In Spain, for example, groundwater (more specifically, application efficiency) through irrigators apply less water than surface water the adoption of “water-saving” technologies in irrigators and achieve higher returns for their order to reduce groundwater use. Subsequently, output per unit of water applied, resulting in groundwater pumping rates declined by more an economic water productivity, on average, of than 50% between the 1970s and 2000. However, 3 over USD 3/m , compared with less than USD despite these gains in irrigation efficiency, 3 1/m for surface water irrigators (Shah 2014). In groundwater levels continued to decline over that India, physical crop water productivity (in terms same time period. 3 of yield - kilograms per cubic meter [kg/m ] of Kendy et al. (2003) discussed this outcome water applied]) on groundwater-irrigated farms in the context of the local hydrology. The local can be between one and three times greater shallow aquifers in Luangcheng County are than on farms irrigated with surface water. replenished by rainfall and runoff, and depleted Similar findings have been documented in by water consumption (evapotranspiration). As other studies in South Asia (DebRoy and Shah illustrated in Figure 6, if precipitation is higher 2003). Overall, the higher water productivity than evapotranspiration in a given year, runoff achieved with groundwater irrigation may be the and groundwater recharge occurs. If, however, result of several factors, including lower water evapotranspiration starts to continually exceed applications, production of higher-value crops, annual rainfall, groundwater is mined. The increased capacity to control timing of irrigation focus on food self-sufficiency led to a significant applications, and a tendency for groundwater increase in the region’s irrigated area, and thus farmers to invest more in complementary crop evapotranspiration. Since about 1960, the inputs (such as fertilizers and high-yielding levels of evapotranspiration were higher than seed varieties) given the greater reliability of precipitation and continued to increase until the groundwater (DebRoy and Shah 2003). mid-1970s. Since then up to the conclusion of However, increases in water productivity the study in 2000, annual evapotranspiration resulting from tapping uncommitted flows may remained constant. With a progressive decline in be associated with significant costs. Depending precipitation from the 1960s, groundwater mining on the hydrologic context, and the underlying increased to 200 mm per year in the 1990s. definition for water productivity, costs may occur Overall, while groundwater pumping declined and in various forms, including in terms of groundwater irrigation efficiency improved, the proportion of depletion, reduced water quality, and greater groundwater pumped that was consumed by crops 20 FIGURE 6. Annual evapotranspiration, precipitation and groundwater recharge/mining in Luangcheng County, China (1947-2000). 700 Evapotranspiration Precipitation and ET (mm/y) Runo , 600 recharge Groundwater 200 mm mining 500 Precip itation 400 2000 1947 1951 1955 1959 1963 1967 1971 1975 1979 1983 1987 1991 1995 Source: Based on Kendy et al. 2003. Note: ET = evapotranspiration. increased significantly and return flows to the who reallocate water and shift part or all of aquifers declined (Kendy et al. 2003; Frederiksen their land to higher-value crops tend to improve et al. 2012). their agricultural returns and “economic” water Frederiksen et al. (2012) used the example of productivity, with the extent dependent on market Luangcheng County as part of a larger discussion and other conditions (Molden et al. 2003, 2007a). on the need for precision in water use definitions Reallocating water from agriculture to other and terminology (e.g., water application versus sectors with higher-value water uses is often water consumption), and how imprecision can emphasized as a way of reducing problems of lead to faulty decision making and unintended water stress and contributing to broader societal consequences. According to the authors, the goals. It is seen as a pillar of water demand lessons from this case prompted the Chinese management, making better use of available authorities to shift their focus from reducing water resources as opposed to augmenting supplies. applications to reducing water consumption. In many instances, “irrigation efficiency” tends to be low with a large share of agricultural water withdrawals and irrigation applications not 3.2.4 Reallocate Water among Uses consumed by crops. Thus, it is commonly believed Reallocating water from lower- to higher-value that a focus on improving “irrigation efficiency” uses is one of the means to increase “economic” could free up substantial quantities of water for water productivity (Molden et al. 2003; Molle reallocation to other sectors that often have much 2003b). Reallocations can occur within the higher water values than agriculture. The CA agriculture sector (e.g., from staple grains to program provided a better understanding of the horticulture crops) or across sectors (e.g., from potential for shifting water out of agriculture and agriculture to the municipal or industrial sector). why this type of transfer may often be problematic Within the agriculture sector, values of “economic” (Scott et al. 2001; Molle 2003b; Molle et al. 2007; water productivity (especially in the conventional Molle and Berkoff 2006; Wester et al. 2008). definition of gross value of product relative to In a review of the literature and country water applied) for most major grains are much experiences with intersectoral water reallocations, lower than for vegetables and fruits. Thus, farmers Molle and Berkoff (2009) pointed out that the 21 conventional view, based on the classical notion are desirable or not to achieve broader policy of “irrigation efficiency”, considers farmers’ water or development objectives (Bakker et al. 1999; use as inefficient and wasteful. However, this Barker et al. 2003; Kijne 2003). ignores the fact that much of the wasted water flows back to the river or an aquifer and—subject to water quality—can be recycled downstream. 3.3 Water Productivity and Broader The economic gains from intersectoral water Development Objectives reallocations may also not be as high as expected. For example, if measured in terms of Fundamental to IWMI’s overarching mission, “economic” water productivity, a comparison of and many of the programs led by the Institute, the respective values between the agriculture is an effort to understand the extent to which and industrial sectors can be misleading, since improving agricultural water productivity can water is only a tiny portion of the overall costs in help in achieving food security, responding to many industries. Furthermore, in the context of pressures to reallocate water to cities and for the assessing intersectoral water allocations, other environment, contributing to economic growth, social and environmental, but also political, costs and alleviating poverty (Molden 2007). Starting associated with transfers are not easily estimated in 2000, when David Seckler as Director General and thus often not included in the calculations. led the transition from the International Irrigation In an analysis of the economics of water Management Institute (IIMI) to the International productivity in agriculture, Barker et al. (2003) Water Management Institute (IWMI), the Institute’s emphasized that an increase in water productivity mandate was to “contribute to food security and as a result of a reallocation of water among users poverty eradication by fostering the sustainable may, or may not, result in higher economic or increases in the productivity of water through the social benefits. In discussing the complexities management of irrigation and other water uses in economic analysis in relation to efforts for in the river basin” (IWMI 2015b). In the same increasing water productivity, they state, “As the year, IWMI launched the CA program with an competition for water increases, decisions on overarching research question of “how can water basin-level allocations among sectors must involve in agriculture be developed and managed to help value judgments as to how best to benefit society end poverty and hunger, ensure environmentally as a whole. This will include setting priorities sustainable practices, and find the right balance in the management of water resources to meet between food and environmental security” (Molden objectives such as ensuring sustainability, meeting 2007). The CPWF continued this journey with food security needs, and providing the poorer an explicit focus on the linkages between water segments of society with access to water” (Barker productivity and water poverty (Fisher et al. 2014), et al. 2003, 30-31). while WLE has extended these earlier objectives Together, the research across the four with an additional effort to explore gender and pathways to increase water productivity has social equity dimensions of water productivity highlighted the importance of grounding water in the context of sustainable intensification and management decisions in the hydrological, ecosystem values (IWMI 2014). social, economic and environmental context, This section presents in more detail how and the need to understand the trade-offs at IWMI’s research has contributed to understanding different scales. Risks and cost considerations the relationship between interventions to improve (economic, social and environmental) for farmers water productivity and their contribution to different and for society as a whole may go unnoticed in development objectives. Two key objectives are the promotion of water productivity-enhancing increasing agricultural production to meet rising practices. Yet, these costs need to be considered food demands and reducing agricultural water (even if it is only qualitatively) to determine use to facilitate reallocations to other sectors. whether improvements in water productivity Two additional objectives that may be linked to 22 the others are raising farm-level income, and of additional irrigated lands (Seckler 1996). alleviating poverty and inequity in the agriculture These impressions were given in the context sector. In many instances, water productivity of declining irrigation development investments, interventions have embraced more than one and growing competition for water from other development objective. sectors (mainly urban and industry) and to meet environmental needs (Seckler et al. 1998). These factors placed a stronger urgency 3.3.1 Increasing Agricultural Production to on improving the productivity of existing Meet Rising Food Demands agricultural water supplies to meet future food Concerns over food security and growing demands. water scarcity were at the heart of the call Consequently, a large part of the early IIMI/ for improved agricultural water productivity in IWMI research on water productivity was focused the mid-1990s. Seckler and his colleagues at on measures and pathways to increase yield IIMI (Seckler 1996; Seckler et al. 1998, 1999) (particularly of staple crops) per unit of water stated that, for many countries, particularly in consumed to contribute to rising food demands. arid regions, water had become “the single Research indicated considerable scope for raising greatest threat to food security, human health yield relative to water consumption, and promising and natural ecosystems” (Seckler et al. 1999, field results were documented (see section 3.2.1). 29). World food reserves were at an all-time An illustration is Figure 7, which shows significant low. Unstable water regimes (and consequently variations in the water productivity of wheat unstable food supplies and rural livelihoods) measured in terms of water consumed in different fueled social and political instability in parts regions of the world, suggesting considerable of sub-Saharan Africa. In India, food security scope for raising the amount of yield relative to was “crucially” dependent on the development ET in different wheat-producing areas. FIGURE 7. Variations in the water productivity of wheat (kg/ha/ET) in different regions. North American Great Plains China Loess Plateau Envelope for attainable water productivity Mediterranean Basin Southeast Australia 6 Yield (metric tons per hectare) 5 4 3 2 1 n = 691 0 0 100 200 300 400 500 600 Evapotranspiration (millimeters) Source: Molden et al. 2007b, adapted from Sadras and Angus 2006. Note: ET = evapotranspiration. 23 In this regard, research conducted by IWMI such as cities, industry and the environment and partners also explored the linkages between (Molle and Berkoff 2006). Seckler (1996) water productivity and agricultural productivity, highlighted the growing number of water-scarce and showed that they are not straightforward. countries turning to water reallocation as a Studies carried out by IWMI and the CA (e.g., solution. The SWIM and CA programs explored Hussain et al. 2000, 2003, 2004, 2007; Kumar et the extent to which improvements in agricultural al. 2009) made some progress in identifying and water productivity can free up water for non- quantifying the contribution of the different factors agricultural uses (e.g., Hong et al. 2000; Scott affecting crop yields, but the importance and et al. 2001; Molle 2003b; Molle and Berkoff magnitude of each factor’s contribution was found 2006; Molle et al. 2007; Wester et al. 2008). to vary significantly by physical location, and Molle and Berkoff (2006) carried out a review the related hydrologic and climatic setting. More of intersectoral water transfers based on 19 fundamentally, the research findings impressed case studies from North America, Europe, South the point that farm-level decisions regarding Asia, Southeast Asia, China, the Middle East cropping pattern and water use are influenced and Latin America. The study found an overall by a range of context-specific (water- and non- mixed picture in terms of the success of water water-related) factors. Thus, reliance on water reallocations, and apropos to this paper, the productivity values in isolation can mask important extent to which gains in water productivity played variables affecting agricultural production (Lautze a role in this process. Two contrasting cases et al. 2014). Consequently, policy actions aimed from IWMI’s research carried out in the Yangzte at improving water management for food security and Yellow river basins illustrate this point (Hong need to consider the range of factors and et al. 2000; Loeve et al. 2004a, 2004b, 2007; resource constraints that influence farm-level Molden et al. 2006, 2007a). production and marketing decisions, many of In the Yangtze River Basin, the research which have no relation to water (Wichelns 2003, focused on the Zhanghe Irrigation District in Hubei 2014b; Lautze et al. 2014). Province. During the 1990s and early 2000s, the proportion of water received for irrigation (rice 3.2.2 Reducing Agricultural Water Use to production) from the main reservoir declined Facilitate Reallocations to Other Sectors significantly as the water was reallocated to other sectors, including hydropower, industry and Improving water productivity in agriculture has domestic use (Molle and Berkoff 2006). The long- also been seen as a means to reallocate water term trends in water releases for irrigation and to meet the growing demands from other sectors, other uses are provided in Table 6. TABLE 6. Water inflows and releases from the Zhanghe Reservoir, Hubei Province, China (1966-2004). Period 3 Average water use (million m x 100) Rainfall (mm) Irrigation Industrial Municipal Hydropower Flood control Evaporation Inflow 1966-1978 6.03 0.17 0.00 0.25 0.15 1.24 6.94 952 1979-1988 3.62 0.37 0.09 0.53 2.27 1.19 7.53 967 1989-2001 2.21 0.48 0.16 2.76 1.98 1.22 8.82 945 2002-2004 0.62 0.56 0.24 4.28 0.33 0.80 7.86 868 Source: Loeve et al. 2007 24 To facilitate reallocations, a suite of the reallocation of water across sectors may have complementary technical, managerial and policy been successful and supported by an alignment interventions was introduced over time. Farmers of various interventions, the extent to which water were charged a volumetric fee for water supplies, productivity gains played a role in this process is on-farm water conservation practices (such as not clear. the use of alternate wetting and drying, and Research on the experience of the recycling of drainage water) were introduced, Liuyuankou Irrigation District, located in the and ponds were constructed or rehabilitated to chronically water-stressed Yellow River Basin, capture rainfall and reduce farmers’ reliance on provides a contrasting case. To meet demands the reservoir water. In addition, the irrigation from other sectors, surface water allocations operators responsible for allocating water across for agriculture in the district were reduced from sectors received higher water fees from cities 87% to 63% between 1968 and 2000 (Molle and and industries. This pricing system incentivized a Berkoff 2006). While the objective of reallocation reduction in allocations for irrigation. At the same was the same as in the Zhanghe Irrigation time, provincial authorities formally negotiated District, the necessary interventions to support it the water allocations across sectors to ensure were not in place at the different scales. Farmers sufficient releases for irrigation to meet food paid only a flat fee for surface water supplies, production goals. water conservation practices were not promoted, As shown in Table 7, despite significant and groundwater as a supplementary source of reductions in water releases for the Zhanghe irrigation water was not included in the official Irrigation District and associated declines in water allocation plans. System managers were planted area, rice production did not similarly accountable only for delivering less surface water decline and yields doubled. As a result, water to farmers. The fees collected by the managers productivity in terms of yield per unit of water were based on the amount of the area irrigated, supplied (in this case, water withdrawn) increased and no fees were received from the other sectors. significantly. However, the fact that farmers The outcome was that, while surface water reused drainage water and had access to withdrawals for agriculture were reduced, farmers alternative sources of water (e.g., farm ponds) adjusted by pumping additional groundwater. No suggests that water productivity gains may not technical, financial or institutional incentives or have been achieved in terms of production per other mechanisms were put in place to restrict unit of water consumed (Roost et al. 2008). Also groundwater use for agriculture, with the result unclear are the impacts of the changes in return that overall annual groundwater withdrawals for flows on downstream users. Furthermore, while agriculture remained largely unchanged (Molden TABLE 7. Annual rice production, water supply and water productivity in the Zhanghe Irrigation District, Hubei Province, China (1966-2004). Period Rice Water supply Water productivity 3 3 (Mm ) (kg/m ) Planted area Production Yield (‘000 ha) (‘000 tons) (tons/ha) 1966-1978 173 698 4.04 850 0.87 1979-1988 149 1,001 6.72 774 1.44 1989-2002 118 934 7.98 396 2.54 2003-2004 107 894 8.34 141 8.76 Source: Adapted from Loeve et al. 2007. Notes: Planted area accounts for multi-cropping in parts of the district. Water productivity is measured as yield per unit of water withdrawn from the Zhanghe Reservoir and other sources under the control of the Zhanghe Administrative Bureau. 25 et al. 2007a; Loeve et al. 2004b). Figure 8 shows Second, potential trade-offs, such as those the trends in water diversions from the Yellow resulting from farmers’ shift to other water sources River and groundwater withdrawals for the period and other adjustments, need to be taken into 1968 to 2000. account when assessing outcomes. Third, unless Several key points emerge from the research the suite of interventions is complementary, related to the two irrigation systems. First, it is moving water supplies from agriculture to important to be clear how water productivity and other uses may prove to be difficult and trigger associated gains are defined and measured, unintended consequences (Molle et al. 2007; and how they relate to the pursued objectives. Molden et al. 2007a). F I G U R E 8 . Wa t e r u s e t r e n d s i n t h e L i u y u a n k o u I r r i g a t i o n S y s t e m , H e n a n P r o v i n c e , C h i n a (1968-2000). 1,600 Yellow River diversion Yellow River diversion (5-year moving averages) 1,400 Groundwater (5-year moving averages) 1,200 Million cubic meters 1,000 800 600 400 200 0 1968 1973 1978 1983 1988 1993 1998 Source: Based on Molden et al. 2007a. 3.3.3 Raising Farm-Level Income explore the impacts of “water-saving” technologies on farm income (Ahmad et al. 2006, 2007a, A third development objective for improving water 2007b, 2014). As noted in section 3.2.2, the main productivity is to raise farm-level income. This can factors contributing to farmers’ adoption of the be done, for example, by increasing production technologies were increased yields and reduced in a given cropping pattern or by changing the input costs. In a 2004 survey of 168 farmers in cropping pattern with a move to higher-value the Punjab Province of Pakistan who had adopted crops (Molden et al. 2003). For IWMI, a key zero tillage or laser leveling technologies, the focus of research was on farm-level economic majority (87% for zero tillage and 88% for laser impacts of technologies that reduce the amount leveling) reported a decrease in production costs of water withdrawn, applied or consumed. For (Ahmad et al. 2007b, 2014). With yields also example, one objective of IWMI’s research on increasing or remaining the same for most of the “resource conservation” technologies was to farmers surveyed, net farm incomes likewise rose. 26 Table 8 shows the percentage of farmers improved productivity and profitability following reporting an increase, decrease or no change the adoption of micro-irrigation technologies in yield, cost of production, and net farm income could have important sustainability implications by following the adoption of zero tillage and laser increasing (rather than decreasing) the demand leveling technologies. for irrigation water, particularly when coupled Similar research was carried out on micro- with financial subsidies. Specifically, the authors irrigation technologies to assess their impacts noted a trend towards year-round cropping, which on, among other things, farmers’ incomes. A could result in greater water use in terms of study in the Indian states of Maharashtra and water withdrawals, application and consumption. Gujarat found that investments in micro-irrigation These findings further highlight the need to technologies (including drip and sprinkler systems) consider the range of possible impacts on multiple are generally profitable with farmers able to development objectives when designing or recoup their initial investment within 1 to 3 years, promoting (including with subsidies) interventions with available subsidies further improving the to increase water productivity. returns. Farmers reported that the technologies enhanced water productivity (in terms of water 3.3.4 Alleviating Poverty and Inequity in the applied) as well as the productivity of other Agriculture Sector agricultural inputs, thereby reducing the cost of production (Namara et al. 2005). A fourth key development objective for IWMI However, while adopters of micro-irrigation and its hosted programs has been to examine technologies usually reported gains in both yield opportunities for alleviating poverty and inequities and profitability, the majority of adopters were in the agriculture sector through irrigation-related wealthier farmers, suggesting that the poverty interventions, including gains in water productivity. impact was not substantial. Moreover, in both Early research conducted by the CPWF explored Maharashtra and Gujarat, micro-irrigation adopters the link between water productivity gains and the produced more water-intensive crops than non- alleviation of poverty and inequity. The research adopters and also increased cropping intensity. built on an implicit assumption that the “poor were Consequently, Namara et al. (2005) cautioned that also ‘water poor’” (CPWF 2015). TABLE 8. Farmers’ perceptions of the impact of zero tillage and laser leveling on yield, cost of production and net farm income, Punjab Province, Pakistan. Yield Cost of production Net farm income Zero tillage Increase 54 6 67 Decrease 30 87 23 No impact 16 7 8 Laser levelling Increase 96 8 96 Decrease 0 88 0 No impact 4 4 4 Source: Ahmad et al. 2014. Note: Based on a 2004 survey of 168 farmers. 27 Conceptual aspects of this work began in social environment” (Kemp-Benedict et al. 2011, the early 2000s (e.g., Prasad and Watson 2003; 135). This, in turn, suggests the need for multiple Hussain and Giordano 2004; Prasad et al. 2006) criteria to understand the linkages between water and continued in a more applied set of studies and poverty as well as inequity. in 10 basins located in Asia, Africa and South Complementary research conducted by the America (Kemp-Benedict et al. 2011, 2012; Cook CPWF suggested that water productivity and et al. 2012). Over time, researchers identified poverty are only weakly related, and there is no a set of five interlinked aspects that define the clear relationship between poverty and water relationship between water and poverty (Kemp- scarcity within a basin (Fisher et al. 2014). Benedict et al. 2011): Researchers found that the severity of poverty is more dependent on the level of control than ● Scarcity (when people are challenged to the physical endowment of water (Namara et meet their livelihood goals due to water al. 2010); and stronger linkages exist between scarcity). poverty and other factors, such as access to ● Access (when people lack equitable basic services—ranging from safe drinking water access to water). and sanitation to healthcare, education, finance, markets and farm inputs (Fisher et al. 2014; Vidal ● Low water productivity (when people et al. 2014). Moreover, where relationships were acquire insufficient benefits from water found between the provision of natural resources use). (such as irrigation water) and livelihood outcomes, ● Chronic vulnerability (when people are these were more closely associated with the level vulnerable to relatively predictable and of economic development and institutional factors repeated water-related hazards, such as (Molle 2003a; Cook et al. 2009; Kemp-Benedict seasonal floods and droughts, or endemic et al. 2011; Fisher et al. 2014). In other words, disease). poverty is more dependent on the stage of a basin’s economic and institutional development ● Acute vulnerability (when people suffer an than the availability of water resources (Cook et impaired ability to achieve livelihood goals al. 2012; Vidal et al. 2014). Irrigation may play a as a consequence of large, irregular and role in improving livelihood outcomes, but only episodic water-related hazards). alongside improvements in other contributing The research also demonstrated that the factors, including access to markets and credit, nature of these linkages and the role of improved as well as a supportive institutional environment water productivity in addressing them is complex. (Kemp-Benedict et al. 2011). Kemp-Benedict et al. (2011) argued that the Complex linkages were also found in relation five aspects of water-related poverty must be to water productivity and equity, in that water considered within a broader context of institutions, interventions could either reinforce or reduce variability (natural, social and economic), and inequities (e.g., Clement et al. 2011a, 2011b; household and community assets. Specifically, Mapedza et al. 2008). Within a community, the the authors state: “Deprivation as a result of water benefits derived following the introduction of scarcity reflects a lack of natural assets; equitable technologies or practices aimed at improving access is determined largely by institutions; water productivity could benefit some farmers vulnerability to water-related hazards is largely more than others (Ahmad et al. 2007a, 2007b, (although not entirely) due to variability in the 2014). For example, as illustrated in section natural environment; low water productivity is 3.2.2, the adoption of technologies aimed at affected by household and community assets, improving water productivity can disproportionately such as access to markets or knowledge; and benefit some categories of farmers. This is not loss of livelihood due to change is a consequence to say that improvements in water productivity of variability in the external natural, economic, and necessarily further increase inequity. However, 28 it is important to identify preexisting inequities aims. The research reinforces the need to be in access to water and other resources among clear about the definition of water productivity to farmers and communities in order to better target understand the possible trade-offs, and cautions poor communities, and/or avoid exacerbating against relying solely on water productivity inequity in the agriculture sector (Clement et al. indicators for decision making. The selected 2011b). pathway(s) to promote water productivity Overall, this large body of applied research on improvements must consider scale; the hydrologic, water productivity and the broader development socioeconomic, policy and institutional context; objectives has contributed a greater understanding and the differing perspectives across actors, of the role of context and when, how, and for the factors influencing them, and related what purpose improvements in water productivity adaptation strategies. Without due consideration can be desirable. Improving water productivity of these context-specific elements, well-intended is not the ultimate goal, but rather can serve as interventions may result in unintended social or a pathway to achieving broader development environmental consequences. 4. Lessons Learned: Reflecting on Two Decades of Water Productivity Research Since the 1990s, significant conceptual and water. The concept and related terms helped methodological advancements and insights to highlight the importance of scale and the have emerged from applied research on notion of recycling water within a river basin, agricultural water productivity. Through that allowing for a better understanding of whether research, a more nuanced understanding of a “piecemeal change” (i.e., increasing irrigation the concept has also emerged, highlighting efficiency on a farm) represents a “real” its usefulness and limitations, as well as its improvement in terms of water saving at the operationalization and contribution to broader basin scale or not (Seckler 1999). development objectives. Some of the main As alluded to in previous sections, a strong lessons learned from the research on water debate and some disagreement continues in productivity in the literature published by IWMI the literature on how water productivity and and others are highlighted below. efficiency terms are to be defined and used (e.g., Jensen 2007; Perry et al. 2009; Frederiksen et Lesson 1: Key terms need to be properly al. 2012; van Halsema and Vincent 2012; Pereira defined and discussed et al. 2012; Kambou et al. 2014; Heydari 2014; Agricultural water productivity, introduced in Wichelns 2014a). Some aspects of the debate are IWMI Research Report 1 (Seckler 1996) in an new, but to a large extent it comes back to the effort to better address growing water scarcity, fundamental conceptual and practical challenges stimulated important conceptual developments Seckler outlined in his early writings on the topic in the field of water resources management. (e.g., Seckler 1996, 1999). Already in the late It challenged researchers and practitioners to 1990s, he characterized the circular debate using think beyond the traditional notions of “irrigation a quote from André Gide’s Le traite du Narcisse efficiency” in the use of irrigation water, and of 1891: “Everything has been said before, but consider more broadly the net benefits received since no one listens, one must always start again” in agriculture and other sectors from the use of (Seckler 1999). 29 Many reports and much of the public hydrologic setting is also required to ensure that debate continue to be vague on the meaning a proposed intervention fits the local context and of “water productivity” and the different achieves the desired effects (Molden et al. 2001b; notions of efficiency, often using the terms Kendy et al. 2003). interchangeably—with little discussion on how To illustrate, interventions such as the to define and measure them, what to do for promotion of drip or sprinkler irrigation improving them and, importantly, how to monitor technologies have gained considerable attention and assess changes (Scheierling et al. 2014, as a means to save water in agriculture—based 2016). The terms then become generic to on the assumption that, by increasing the label an array of performance indicators and proportion of water applied that is beneficially even development objectives. In part, this used by crops, less irrigation water would be is due to the multi-disciplinary nature of the needed (and water can be freed up for other topic, with different disciplines using different purposes). This may be the case with regard definitions (and promoting different interventions), to the amount of water applied at the field and with relatively limited exchange between level— if farmers do not have incentives to the disciplines. The CA and its successor apply the same amount of water as before in programs made progress in bridging disciplinary order to expand the irrigated area or intensify boundaries. Further discussion would clearly production. Even if the amount of water applied benefit from more intensive interdisciplinary is reduced, the consumptive water use of collaboration and outreach to the general public the crop may stay the same and no “real” and decision makers. water savings would be achieved at the basin scale. In fact, research has shown that such Lesson 2: Understanding of the hydrological interventions may even increase consumptive setting and appropriate scale is critical water use, and thus overall depletion at the The concept of agricultural water productivity basin scale, unless accompanying measures initially evolved as a means of producing more are undertaken (Ahmad et al. 2007a, 2007b; agricultural output with the same amount or less Ward and Pulido-Velazquez 2008; Dagnino water. A wide range of interventions has been and Ward 2012; Pfeiffer and Lin 2014; Fishman proposed to promote improved water productivity. et al. 2015). An example to at least partially To understand where and how productivity gains address this problem is a measure that was can be made—and possibly also “real” water introduced in the Arkansas River Basin, savings achieved—requires consideration of the United States, where surface water users specific hydrological setting, and the appropriate were required to return the reductions in spatial and temporal scale of analysis. There water applications (and withdrawals), which is no ‘one-size-fits-all’ approach (Seckler et were made possible due to the adoption al. 1999). Achieving a desired improvement in of improved irrigation technologies, to the water productivity requires an understanding river (Harvey 2014). Thus, the promotion of of the water balance in a given domain and such interventions for achieving real water a clear definition of “water productivity.” With savings should target locations where return growing water scarcity, the interdependencies flows would otherwise be lost in a sink, or among water users increases and gains from be accompanied by mechanisms that limit the use of water in one location may result in the potential increase in consumptive use. losses in another; for example, the opportunity Proper water accounting at local and basin to beneficially recycle water returning from an scales, coupled with an understanding of irrigated field to a surface water or groundwater the institutions that govern water allocation source may be reduced, if its quantity or quality and application, and consumptive use, are is diminished by an intervention on the irrigated necessary prerequisites for effective water field (Seckler 1999). An understanding of the productivity interventions. 30 Lesson 3: Interventions need to be aligned on the agricultural and environmental services with the objectives and incentives of various these systems provide (Rebelo 2016). The water decision makers balance quadrant framework is another recent development aimed at identifying hydrologic At the policy level, improvements in agricultural contexts in which “water-saving” technologies may water productivity are usually called for in be promoted without risking reduced return flows connection with the need to meet rising food for downstream users (Batchelor et al. 2014). demand or to reallocate water to other uses. The challenge is to bring these more advanced Farmers, though, may be interested in these approaches into the broader policy discussions to objectives only insofar as they contribute to improve the design and outcomes of interventions maintaining or increasing farm-level income—with related to water productivity. water being only one of many often dynamic and context-specific factors affecting crop Lesson 4: Well-intended interventions may production and decision making. If, for example, result in unintended consequences water productivity-enhancing technologies or management practices generate more on- Without due consideration of context-specific farm costs (including uncertainty or risks) than elements, well-intended interventions may result in additional benefits, their adoption may not be a unintended (and often undesirable) consequences, priority for some or all farmers (as the farming ranging from hydrological to environmental, social community itself is not homogenous). These and financial/economic changes. An illustration is often conflicting objectives across water users provided in section 3.2.2 involving the adoption and decision makers at different scales, as well of “resource conservation” technologies in as the different incentives they face, need to Pakistan, which led to increases in yields, water be taken into account when designing policies productivity (in terms of yield per unit of water or promoting interventions to enhance water applied), and farm profits. Among the unintended productivity. Otherwise, “farm-level responses to consequences were higher water consumption policy parameters may be different than expected, as well as an increase in groundwater use at the and the goals of water management policies may cost of downstream users and uses, including the not be achieved” (Wichelns 2003, 100). environment. Preexisting inequities among farmers Tools are needed to place these different with different farm sizes were also exacerbated. perspectives in context, so that the various factors There may be other unintended influencing different users and decision makers consequences and trade-offs (Guerra et al. at various levels can be identified, and the costs 1998; Barker et al. 2003; Kijne 2003; Hsiao et and benefits generated from improvements in al. 2007; Sadras et al. 2011). Water productivity water productivity can be estimated. This should improvements involving higher yields may come include assessments of how the costs and in the form of more polluted drainage flows benefits are likely to be distributed (Barker et al. due to farmers’ more intensive use of fertilizers 2003; Barker and Levine 2012). Studies in water and pesticides. Furthermore, water productivity accounting, as well as hydro-economic simulation improvements associated with investments in and optimization models, are increasingly part of better technologies or practices may affect the tool kit. Research conducted by IWMI and farm-level incomes due to high investments others is helping to better understand and quantify and operational costs, and possibly additional some of the complex interactions. Recent updates labor or management requirements. This is to the Water Accounting Plus (WA+) framework, often used as a rationale for providing public for example, allow users to assess not only subsidies to facilitate investment decisions. water flows, fluxes, stocks and consumption in Moreover, yields (and farm-level incomes) may large, complex river basins, but also the potential decrease with interventions that aim at reducing impacts of different water management strategies the consumptive water use of crops for achieving 31 real water savings, such as deficit (or partial) Wichelns (2014a) illustrates with typical crop-water irrigation. Higher risk is another potential trade- production functions, the point of maximum water off from adopting “water-efficient” technologies productivity may be very different from the point and practices as is increased exposure to market of maximum crop yield—even in the simplest case fluctuations through the production of marketable of one output and one input (water). It may also crops. Poor farmers who often have less ability or be quite different from the point of maximum net resources to cope with or manage risk may then revenue (which has implications regarding the be disproportionally affected (van Ittersum et al. contribution to the third development objective of 2013). As mentioned in section 3.3.4, depending raising farm-level income). More complications on the context and preexisting inequities, water in determining whether a contribution to the productivity interventions can either reduce or first objective has been made arise when water reinforce inter-household inequities (Barker productivity estimates are compared over and Levine 2012; Clement et al. 2011b). different crop types and over time. Without further Consequently, estimates of changes in water information and analysis, it is not obvious which productivity may not be useful to assess policy situation should be preferred over the other and interventions unless the possible trade-offs— whether the change helped to increase agricultural such as effects on downstream users, increased production or not. risk and uncertainty, and rising inequities—are Similarly, when assessing the contribution properly incorporated (even if only qualitatively) of improved water productivity to the second into the assessments, and efforts are made to development objective of reducing agricultural minimize them (Bakker et al. 1999; Barker et al. water use, a number of issues need to be kept 2003; Kijne 2003; Wichelns 2014a, 2014b). in mind. Besides noting whether the change occurred in the numerator or denominator of Lesson 5: Improving water productivity is not the ratio, it is important to pay attention to a goal in and of itself which water measure is used and which scale Improving agricultural water productivity must not incorporated. In addition, the context needs to be seen and pursued in isolation. IWMI’s research be considered—in particular, whether return has shown that it is not a “principle objective” or flows matter for downstream uses—to determine an end in and of itself (Rijsberman 2006; Vidal whether real water savings were achieved. et al. 2014). Rather, it needs to be integrated Broadly speaking, when return flows do not with, and contribute to, broader development matter (for example, if they flow to a salt sink that objectives. As discussed in section 3.3, the four prevents reuse), a focus on optimizing the share main objectives are: (i) increasing agricultural of water applied for crops’ transpiration needs production, (ii) reducing agricultural water use, may be justified (for example, with the adoption of (iii) raising farm-level income, and (iv) alleviating “resource conservation” technologies, coupled with poverty and inequity in the agriculture sector. a limit on the expansion of the irrigated area). If Research conducted by IWMI and partners return flows do matter, the focus may need to be has also suggested that the relationship on reducing water consumption, because only this between water productivity and these broader reduction could be considered as “saved” water objectives is not straightforward. For example, that is available for reallocation without affecting with regard to the first development objective downstream uses. of increasing agricultural production, it is not On the fourth development objective, IWMI’s clear if a contribution has been made when a research has shown that there is no simple water productivity measure increases and more link between water productivity improvements output per input of water is produced. The ratio and poverty or equity. Technology-oriented may have increased due to a reduction in water interventions may even be associated with trade- use (however defined) while output remained offs between poverty reduction and equity (section constant or even decreased. Furthermore, as 3.3.4). It is, therefore, important to assess the 32 constraints faced by poor irrigators (not only As illustrated in section 3, this broadened with regard to access to water, but also to other definition has likewise faced conceptual resources), and properly design and target challenges, but the related research has also interventions. provided greater clarity on both the contributions and limitations of agricultural water productivity Lesson 6: Limitations of single-factor metrics. On its own, agricultural water productivity productivity metrics must be kept in mind may be considered as a weak proxy variable for Similar to land productivity or labor productivity, the objectives that are indeed of interest (section agricultural water productivity focuses on one 3.3). However, when considered in context and factor in a multi-factor, and usually also multi- as part of a larger suite of indicators, measures output, production process. In general, single- of water productivity can give a first approximation factor productivity metrics do not give a full of the situation and help to identify outliers. They picture of the natural, market or policy context can also provide a basis to generate and test in which agricultural production takes place. For hypotheses on the underlying causes for the example, water productivity ratios expressed in differences and, with further analysis, suggest 3 kilograms per cubic meter (kg/m ) or US dollars possible interventions (Fuglie 2014). 3 per cubic meter (USD/m ) are often used for Lesson 7: New technologies and data sources making comparisons across users, sectors and should be increasingly used and cross- over time. It is then important to keep in mind disciplinary approaches promoted that different water productivity values do not necessarily reflect water-related issues, but may The creation of water accounting frameworks be the result of many other factors and their has been fundamental to the improved respective intensity of use, and, depending on the application of the water productivity concept. formulation of the ratio, also the result of different Water accounting has provided a framework outputs and their related prices. Such data to understand how water is used and reused can, therefore, provide only an incomplete, and within and across sectors at various spatial potentially misleading, picture of the underlying scales. Tools such as hydrologic models coupled drivers of water productivity, especially when used with crop models, and data generated with in isolation (Barker et al. 2003, Lautze et al. 2014; remote sensing technologies, have allowed Scheierling et al. 2014). researchers to estimate average current and It is these conceptual challenges that Seckler potential water productivity; identify locations with encouraged IWMI and the broader research high and low water productivity; explore possible community to address, so that water management entry points (technical, managerial or policy) to projects are designed and implemented “in improve water productivity; and understand the a much better way—from all the important potential consequences within and outside of technical, economic, social, and environmental the agriculture sector, including the effects on perspectives” (Seckler 1996, 3). Early on, ecosystems (Karimi et al. 2012, 2013a, 2013b; IWMI researchers cautioned that a focus on a Rebelo et al. 2014). single-factor productivity metric in agricultural However, data constraints continue to limit the production processes with multiple factors may application of even single-factor water productivity provide misleading results from the perspectives metrics—even in developed countries. For of the farmer and the economy as a whole. instance, the United States Geological Survey Consequently, IWMI argued for a broadened (USGS) discontinued calculations to estimate definition of agricultural water productivity—one return flows and consumptive water use due to that includes a wider perspective on water use resource and data constraints in 1995; since and the related benefits, costs and risks that may then, USGS has relied on estimates of water accompany its improvements (Bakker et al. 1999; withdrawals rather than water depletions as the Barker et al. 2003; Molden et al. 2007b). basis for its semi-decadal report on water use 33 (Maupin et al. 2014). Continued development of and efficiency, which explicitly includes water water accounting and remote sensing tools (e.g., aspects in the measurement of productivity United Nations 2012; Karimi et al. 2013a; Tilmant and efficiency, showed that the field offers a et al. 2015) is needed to lessen the constraints number of useful approaches to assess multi- of data limitations, and enhance the ease and factor production processes, including total precision with which water productivity estimates factor productivity indices and frontier models can be made at multiple scales. (Scheierling et al. 2014). Deductive methods, The development and application of other such as hydro-economic models, which are approaches from related disciplines could often applied in irrigation water economics also provide new insights and opportunities could also be used more specifically to assess for improving the definition, assessment and agricultural water productivity in a multi-input analysis of agricultural water productivity and and multi-output framework (Scheierling and efficiency. In economics, especially in the Tréguer 2016). These findings suggest an field of agricultural production economics, opportunity to advance economic assessments aspects related to productivity and efficiency of agricultural water productivity, and to provide have been defined and analyzed using more insights, in combination with other disciplinary comprehensive approaches, taking into account approaches, on how water could be used better a range of production factors. A recent survey in different contexts and in support of different of the literature on agricultural productivity development objectives. 5. Conclusions In the preceding sections, we discussed the In the rich body of literature on agricultural concept of agricultural water productivity and water productivity that has evolved over the its evolution from different efficiency concepts; past 20 years through research conducted by the development of further indicators to assess IWMI and partners, a shift becomes apparent and measure change across a range of uses from more theoretical deliberations (the need and scales, and their applications; the scope for to produce more crops with the same or less water productivity gains in different contexts and amount of water) to a more practical discussion scales, and the related pathways; as well as the (where, why, and how to achieve this). Based rationale and thinking behind the importance of on the methodological developments and applied improving water productivity, and the contribution research, a number of key lessons emerge: scale to broader development objectives. The report and context matter, and so do objectives and highlighted the need for precision in defining incentives as well as data and approaches. This water productivity terms, and discussed their body of research suggests that the inherent value limitations. The importance of water accounting as of single-factor water productivity metrics may an adaptable framework for estimating water uses not be as variables to be maximized but rather and identifying opportunities for improvements as initial, albeit imperfect, indicators for regions has been stressed. Progress in the use of remote with increasing water scarcity of the potential for sensing to generate additional data for use in improvements; and as a basis for further analysis water accounting, and in integrated crop and of the underlying causes for the differences, the hydrologic modeling, at a range of scales has also possible interventions (that may or may not be been discussed. related to water) and their likely impact. 34 Reflecting on these lessons is particularly and limitations, particularly in relation to water relevant given the adoption of the United Nations savings—and to consider agricultural water Sustainable Development Goals (SDGs) in productivity as part of a larger suite of metrics 2015, and the fact that Goal 6.4 emphasizes the and approaches to help address water scarcity importance of increasing water-use efficiency concerns and achieve broader development across all sectors, including agriculture. With objectives. More intensive interdisciplinary growing water scarcity in many parts of the world, collaboration would help arrive at more improvements in agricultural water productivity comprehensive approaches. Research presented seem to be desirable as a means to reduce here offers possible entry points with remote overall water use in the agriculture sector. sensing, agronomy, hydrology and economic However, whether gains in water efficiency or approaches, in particular from agricultural productivity measured as single-factor productivity production economics and irrigation water metrics are a relevant indicator at different scales economics. To conclude, a focus on agricultural of analysis and in different settings, or whether water productivity has brought greater attention they contribute to broader development objectives, to water scarcity and management issues and depends on a number of complex and interrelated their complexity. 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Guillaume Lacombe and Matthew McCartney. 2016. 165 Controlling Floods and Droughts through Underground Storage: From Concept to Pilot Implementation in the Ganges River Basin. Paul Pavelic, Brindha Karthikeyan, Giriraj Amarnath, Nishadi Eriyagama, Lal Muthuwatta, Vladimir Smakhtin, Prasun K. Gangopadhyay, Ravinder P. S. Malik, Atmaram Mishra, Bharat R. Sharma, Munir A. Hanjra, Ratna V. Reddy, Vinay Kumar Mishra, Chhedi Lal Verma and Laxmi Kant. 2015. 164 Integrated Assessment of Groundwater Use for Improving Livelihoods in the Dry Zone of Myanmar. Paul Pavelic, Sonali Senaratna Sellamuttu, Robyn Johnston, Matthew McCartney, Touleelor Sotoukee, Soumya Balasubramanya, Diana Suhardiman, Guillaume Lacombe, Somphasith Douangsavanh, Olivier Joffre, Khin Latt, Aung Kyaw Zan, Kyaw Thein, Aye Myint, Cho Cho and Ye Thaung Htut. 2015. 163 Demonstrating Complexity with a Role-playing Simulation: Investing in Water in the Indrawati Subbasin, Nepal. John Janmaat, Suzan Lapp, Ted Wannop, Luna Bharati and Fraser Sugden. 2015. 162 Landlordism, Tenants and the Groundwater Sector: Lessons from Tarai- Madhesh, Nepal. Fraser Sugden. 2014. 161 Is ‘Social Cooperation’ for Traditional Irrigation, while ‘Technology’ is for Motor Pump Irrigation? Mengistu Dessalegn and Douglas J. Merrey. 2014. Electronic copies of IWMI's publications are available for free. Visit www.iwmi.org/publications/ Postal Address P O Box 2075 Colombo Sri Lanka Location 127 Sunil Mawatha Pelawatta Battaramulla Sri Lanka Telephone +94-11-2880000 Fax +94-11-2786854 E-mail iwmi@cgiar.org Website www.iwmi.org IWMI is a RESEARCH CGIAR PROGRAM ON Research Water, Land and Center Ecosystems ISSN: 1026-0862 and leads the: ISBN: 978-92-9090-848-7