CGIAR Research Program on Water, Land and Ecosystems (WLE) | Mehta Lyla et al., 'Water for Food Security, Nutrition and Social Justice', , IFPRI, 2019

1. Introduction 2. Linking Water and Food Security and Nutrition (FSN) 3. Agricultural Water Management 4. Water Governance for FSN 5. Water, FSN and Social Justice Index | Non-PR | IFPRI5; CRP5; 1 Fostering Climate-Resilient and Sustainable Food Supply; G Cross-cutting gender theme | EPTD | CGIAR Research Program on Water, Land and Ecosystems (WLE)

In many slums and informal settlements in the global South, the quality of water accessed by poor people is so bad that it adversely affects health and nutrition, especially of children and babies. Moreover, many of these settlements lack adequate sanitation, which contributes to disease, such as diarrhoea, which further contributes to poor nutritional outcomes. Safe drinking water and sanitation are fundamental to the nutrition, health and dignity of all. Despite the progress made in achieving global targets around water and sanitation, about 3 in 10 people, or 2.1 billion lack access to safe, readily available water at home, and 6 in 10, or 4.5 billion, lack safely managed sanitation. Growing water scarcity and variability will increase the competition for water resources across sectors, with water often being taken away from the agricultural sector to drive greater economic value per unit of water in other sectors. The chapter also presents an overview of the key concepts discussed in this book.

Achieving the objectives of sustainable development in water and agri-food systems requires the utilisation of decision-support tools in stakeholder-driven processes to construct and simulate various scenarios and evaluate the outcomes of associated policy interventions. While it is common practice to involve stakeholders in participatory modelling processes, their comprehensive documentation and the lessons learned remain scarce. In this paper, we share our experience of engaging stakeholders throughout the entire system dynamics modelling process. We draw on two projects implemented in the Volta River Basin, West Africa, to understand the dynamics of water and agri-food systems under changing environmental and socioeconomic conditions. We outline eight key insights and lessons as practical guides derived from each stage of the participatory modelling process, including the pre-workshop stage, problem definition, model conceptualization, simulation model formulation, model testing and verification, and policy design and evaluation. Our findings demonstrate that stakeholders can actively contribute to all phases of the system dynamics modelling process, including parameter estimation, sensitivity analysis, and numerical simulation experiments. However, we encountered notable challenges, including the time-intensive nature of the process, the struggle to reach a consensus on the modelled problem, and the difficulty of translating the conceptual model into a simulation model using stock and flow diagrams – all of which were addressed through a structured facilitation process. While the projects were anchored in the specific context of West Africa, the key lessons and insights highlighted have broader significance, particularly for researchers employing PSDM in regions characterised by multifaceted human-environmental systems and where stakeholder involvement is crucial for holistic understanding and effective policy interventions. This paper contributes practical guidance for future efforts with participatory modelling, particularly in regions worldwide grappling with sustainable development challenges in water and agri-food systems, and where stakeholder involvement is crucial for holistic understanding of the multiple challenges and for designing effective policy interventions.