Circular economy has become a popular subject, attracting attention from academics, practitioners, and policy-makers alike. However, despite the excitement surrounding it, the concept of circular economy has been criticized for being vague and having multiple interpretations from different fields. As a result, there is a lack of evidence and guidance for practitioners, making it difficult to put into practice. Our goal is to fill this gap by bridging the design and implementation of circular economy solutions in the water sector. Through an exploratory study of two case studies, we have shown the significance of what we call as “circular water value” in the context of coal mining. This value is strongly influenced by the chemistry, concentration levels and purity of these effluents. We compared the circular value of the two cases (ranging from 2.5 to 6 euros per cubic meter) to the cost of the novel treatment system, developed by the authors through the EU-funded project ZERO BRINE, to capture this value. This allowed us to evaluate the potential for circular economy implementation. We suggest that this circular transition can offer significant opportunities to coal mining regions in enabling a just transition implementation. This is a topic that is increasingly gaining interest among academic and practitioner communities, further triggered by the recently adopted Just Transition Mechanism. This mechanism secures targeted support of 55 billion euro for the period 2021–2027 for the most affected regions within Europe. The concept of “circular water value” introduced in this article can serve as a tool for exploring the creation of emerging circular value chains from coal mines, as well as for other wastewater treatment and resource recovery projects in general.

Cyprus relies on seawater desalination for a large part of its drinking water supply, with reverse osmosis providing more than 95% of the total desalination capacity in the country. Nevertheless, the environmental impacts of desalination for the Cypriot environment remain poorly understood. Using a combination of mining existing governmental and corporate survey data and reports, this study explores the scale of desalination in Cyprus, the impacts on the coastal marine environment and its overall carbon footprint. Surveys of Posidonia oceanica seagrass meadows show strongly reduced density of shoots and leaf surface area, respectively. Analysis of the available data relating to the overall production of desalinated water and energy consumption reveals that 68.7 million m3 of desalinated water were produced in Cyprus in 2017, resulting in the release of 160 ktons of CO₂ equivalent, representing around 2% of the total carbon emissions in Cyprus. The results are directly applicable for understanding the impacts of brine discharge on seagrass meadows, one of the most common types of Mediterranean seabed ecosystems and useful for providing guidance to decision makers as they are striving to achieve a zero-carbon economy. strategies for achieving greater sustainability in terms of reduced CO₂ emissions and less brine discharge are discussed.