This paper aims to develop, evaluate, and analyze win–win transboundary water management strategies during the operating stage of GERD. Using value engineering (VE), functional analysis system technique (FAST), and life cycle cost (LCC), the optimal win–win strategy is determined. The study uncovered four distinct value options for various win–win strategies. According to the study results, the third win–win strategy is the most effective way to help both upstream and down‑stream nations retain peace, as it seeks to encourage riparian countries to collaborate by: i) developing cooperative regulatory policy; ii) switching to renewable energy supported by GERD; and iii) reducing water loss. This study advances our understanding of the topic by providing policymakers with a tool to: i) evaluate win–win strategies for managing trans‑boundary water; and ii) incorporate the added value and functionality into policies regard‑ing transboundary water management