Legal Analysis and Case Study on the Choice between Setting Environmental Flows by Using Reclaimed Water in Non-Permanent Rivers and the Sustainable Management of Groundwater in Southeast Spain

Extending Natural Limits to Address Water Scarcity? The Role of Non-Conventional Water Fluxes in Climate Change Adaptation Capacity: A Review

Water consumption continues to grow globally, and it is estimated that more than 160% of the total global water volume will be needed to satisfy the water requirements in ten years. In this context, non-conventional water resources are being considered to overcome water scarcity and reduce water conflicts between regions and sectors. A bibliometric analysis and literature review of 81 papers published between 2000 and 2020 focused on south-east Spain were conducted. The aim was to examine and re-think the benefits and concerns, and the inter-connections, of using reclaimed and desalinated water for agricultural and urban-tourist uses to address water scarcity and climate change impacts. Results highlight that: (1) water use, cost, quality, management, and perception are the main topics debated by both reclaimed and desalinated water users; (2) water governance schemes could be improved by including local stakeholders and water users in decision-making; and (3) rainwater is not recognized as a complementary option to increase water supply in semi-arid regions. Furthermore, the strengths–weaknesses–opportunities–threats (SWOT) analysis identifies complementary concerns such as acceptability and investment in reclaimed water, regulation (cost recovery principle), and environmental impacts of desalinated water.

Developing a Multicriteria Decision Analysis Framework to Evaluate Reclaimed Wastewater Use for Agricultural Irrigation: The Case Study of Maryland

Groundwater is the main source of irrigation and residential use in the Eastern Shore Maryland, which is experiencing challenges regarding overuse, saltwater intrusion, and diminishing productivity. The Chesapeake Bay is also facing the problem of water pollution due to pollutant loading from agricultural fields and wastewater treatment plants (WWTPs). Using recycled water for irrigation has the potential to alleviate the pressure on groundwater and reduce pollutant loading. The objective of this study was to develop a decision tool to explore the use of recycled water for agricultural irrigation in Maryland using Multicriteria Decision Analysis (MCDA) integrated with Geographical Information Systems (GIS). Four main evaluation criteria were included in the GIS-MCDA framework: agricultural land cover, climate, groundwater vulnerability, and characteristics of the WWTPs as sources of recycled water. Groundwater vulnerability zones were developed using the groundwater well density, water extraction data, and the aquifer information. Then, the most suitable areas for irrigation using recycled water were identified. About 13.5% and 32.9% of agricultural land was, respectively, found to be “highly” and “moderately” suitable for irrigation with recycled water when WWTPs were categorized based on their treatment process information. The results provide a useful decision tool to promote the use of recycled water for agricultural irrigation.