The global water crisis represents a critical and multifaceted challenge, intensified by the impacts of climate change, rapid population growth, and the unequal distribution of water resources. Addressing water management on a regional to global scale necessitates innovative, large-scale systems solutions that integrate advanced technologies, robust policy frameworks, and sustainable management practices. This session aims to examine state-of-the-art research and practical strategies for large-scale water management, emphasizing scalable solutions to mitigate issues related to water scarcity, quality, and accessibility. Key topics include multi-sectoral water impact assessments; behavioral modeling in water use; sustainable infrastructure development; and transboundary water governance, and multiscale modeling of interactions between water energy, food, and ecosystems. The session seeks to promote interdisciplinary dialogue, showcase effective case studies, and identify collaborative pathways among researchers to foster sustainable management of water resources for future generations.