The water-energy-food (WEF) nexus applies systems thinking to transcend siloed sectoral perspectives and foster integrated resource governance. This study identifies six key objectives that an ideal model for the WEF nexus should achieve: ensuring resource security; promoting resource circularity; enabling transferability across spatial and temporal scales and geographic scopes; facilitating comprehensive identification and quantification of resource interactions; integrating economic, environmental, and societal considerations; and ensuring theoretical rigor and empirical solvability. No existing WEF nexus model simultaneously fulfils all six objectives. To address this gap, we develop the first transparent and comprehensive WEF nexus model that achieves all six objectives. The proposed model links water quantity and quality – including pollutants and temperature – with energy and food systems to analyse system-wide water dynamics. The model explicitly represents water-energy interactions, capturing how thermoelectric generation alters water thermal regimes and, in turn, affects hydrological processes. It also accounts for human-water interactions by incorporating return flows of water after human consumption, emphasizing water circularity. The model's applicability is illustrated through an example of the Beijing-Tianjin-Hebei region in China, and its broader empirical and policy relevance is demonstrated through a set of potential scenarios. These advances provide a systems foundation for understanding hydrological science and for developing sustainable, efficient, and equitable resource strategies.