Implementing the One Water Concept in Greece: Evidence from Case Studies and Policy Pathways

A prominent development in environmental engineering and water resource management is the growing adoption of the term “One Water,” which encompasses all categories of water. In practical terms, One Water Concept (OWC) suggests that some municipalities could benefit from combining their traditionally separate water supply and wastewater divisions into a single, unified department. This integration is believed to enable more strategic, efficient, and economically viable approaches to addressing future water challenges. The OWC promotes an integrated approach to water resource management, emphasizing the interconnectedness of water systems and the need for holistic governance. The focus of this paper is on an examination of the implementation of OWC in Greece based on an analysis of recent international case studies, and the identification of the methodological and epistemological challenges. Through critical engagement with current literature and policy frameworks, the study highlights the successes and obstacles in adopting OWC, offering insights into future directions for sustainable water management. The study identifies key challenges such as institutional fragmentation, insufficient reuse infrastructure, and fragmented policy frameworks, while also highlighting opportunities related to digital monitoring, stakeholder collaboration, and investment in green infrastructure. These findings underscore the need for coordinated strategies to advance the One Water approach in Greece.