Water plays a crucial role in our food systems and food security. However, the essential role of water for a functioning food system and the impacts of food systems on water availability and quality have not yet been adequately recognized. Due to a lack of coordination among water and food systems actors, there are siloed water, food security, and nutrition strategies. This paper presents the case to make water pivotal in designing food systems, laying out action perspectives for different actors to move toward what we call “water-responsible food systems”. This paper is based on input from many participants during workshops and existing literature. A food systems approach provides an excellent entry point to link food with water considering climate change and energy. Moreover, collective and cross-cutting actions between actors in food systems are essential to make decisive progress, as well as a common language and insight into the trade-offs of the multiple values of water for a clear prioritization of water use and allocation.

International audience

Attaining sustainable development is one of the most important challenges of the 21st century [...]

Sustainable and integrated management of water, energy, food, and ecosystems requires a coordinated and cross-sectoral approach to manage trade-offs and maximize synergies among these deeply interconnected resources. This line of action is called the water-energy-food-ecosystem (WEFE) nexus approach. This 5-day course provides an overview of WEFE nexus concepts, issues, and approaches to develop the capacities of early- to mid-career professionals in any WEFE or WEFE-adjacent sector, to foster the integrated, equitable, and sustainable management of WEFE resources. This course was co-developed under the umbrella of the CGIAR Initiative on NEXUS Gains by the Center for Water Resources Studies (CWRS), Institute of Engineering, Tribhuvan University, in partnership with the Alliance of Bioversity international and CIAT, and the International Water Management Institute (IWMI). It includes theory as well as practical applications and interactive elements.

Global food security (GFS) is challenged by increasing food demand due to population growth and climate change. International trade and globalization have underpinned GFS until the most recent public health, geopolitical and economic crises, when virtually overnight, the focus of governments has shifted towards domestically and locally produced foods. However, the agri-food sector has limited flexibility, and relatively long periods are needed for fundamental/sustainable changes. One of the crucial factors enabling GFS is the efficient water management, but the required knowledge and capabilities are often lacking regionally/locally. We propose the Centers for Optimizing Water Management in Agroecosystems as a long-term solution. The Centers would be the specialized hubs for promotion of research, innovation and technology transfer, raising the knowledge of stakeholders (farmers, extension and government officials, scholars, students, policymakers and other professionals) and their capacities in water management. These Centers would operate as research/education/technology demonstration entities tailored to the specifics of a particular country/region, aiming to address the most important and pertinent goals and outcomes with a high-spatial-resolution outreach. Finally, the Centers will improve farmers’ livelihoods, contribute to sustainable and efficient use of agro-environmental resources, and increase productivity and food quality, ultimately supporting GFS.

The water-energy-food (WEF) nexus exemplifies the holistic, integrated, and interdisciplinary system approach, emphasizing mutual interactions between water, energy, and food resources. This study presents the first systematic review that critically evaluates the past progress of WEF nexus research from the evidence-based lens of resource interactions, in terms of quantifying the types and the number of interactions studied. Using a novel classification, this review first classifies 834 WEF nexus interaction studies into four classes based on two axes: (1) The type of study (theoretical or empirical) and (2) The extent of resource interactions examined (all six interactions as a 'full' WEF nexus study or fewer interactions as a 'partial' WEF nexus study). Despite the proliferation of WEF nexus studies since 2011, no significant progress has been made towards including more resource interactions over time in either theoretical studies or empirical applications. Moreover, this review shows that: the number of resource interactions examined in empirical applications is much lower than in theoretical studies; the study of physical resource interactions remains dominant; environmental considerations are biased towards water quality and carbon emissions; and there is a misalignment between research questions and empirical methodologies. Further, this review identifies future directions and provides concrete recommendations for aligning future research to jointly achieve Sustainable Development Goals (SDGs) 2, 6, and 7.

The Water–Energy–Food–Ecosystems (WEFE) Nexus Leadership Program in Nepal aims to not only strengthen leadership and negotiation skills, but to create champions equipped with the technical knowledge and tools, and create the enabling conditions (including recognition and support networks) these champions need, to advance equitable WEFE nexus decision-making and implementation.