Viewpoint: The measurement of water access and use is key for more effective food and nutrition policy

The crisis is characterized by both quantity and quality issues, with climate change, population growth, unchecked water use, and crumbling infrastructure exacerbating the problem. The consequences of water insecurity are far-reaching, affecting physical and mental health, economic well-being, and political stability. Water is a vital component of food and nutrition systems, with over two-thirds of the world's freshwater being used for agricultural activities. However, the relationships between water, food, and nutrition have been largely unappreciated due to the lack of precise, high-resolution data on water insecurity. The recent development of the Individual and Household Water Insecurity Experiences Scales has provided a new framework for measuring water access and use, which has significant implications for food and nutrition policy. The measurement of water security has been limited by the focus on physical availability and safety, with few indicators measuring accessibility and use. The Joint Monitoring Programme's drinking water service ladder is a widely used indicator that captures service levels of drinking water infrastructure, but it does not account for the complexities of water access and use. The lack of precise measurement has hindered our understanding of how water insecurity affects human well-being, particularly in relation to food systems and nutrition. The Individual and Household Water Insecurity Experiences Scales offer a more nuanced approach to measuring water security, considering the various types of water access, use, and stability. This framework has the potential to transform our understanding of human well-being, similar to the shift to experiential measures of food insecurity. Experiences of water insecurity should be regularly measured worldwide, as water is of intrinsic value and critical for achieving many other development goals. The Democratic Republic of Congo, despite having 52% of Africa's surface water, has only approximately half of its population with access to improved water. Conversely, countries with limited water availability, such as Saudi Arabia, have sufficient water for personal needs. This highlights the importance of considering the complexities of water access and use, rather than relying solely on physical availability or infrastructure measures. The measurement of water security at the household and individual level is essential for understanding the nuances of water access and use. This approach can provide insights into key food and nutrition outcomes, such as food security and nutrition, and inform the development of more effective food and nutrition policies. The Individual and Household Water Insecurity Experiences Scales offer a powerful tool for measuring water security and monitoring progress towards achieving development goals.