NATWIP - NATURE-BASED SOLUTIONS FOR WATER MANAGEMENT IN THE PERIURBAN: LINKING ECOLOGICAL, SOCIAL, AND ECONOMIC DIMENSIONS

Recent efforts to achieve social, economic, and environmental goals related to sustainability emphasize the importance of nature-based solutions (NBS), as grey infrastructure alone is insufficient to address current challenges. The majority of frameworks proposed in the literature fail to address the full potential of NBS, neglecting long-term results, unintended consequences, co-benefits, and their contribution to achieving global environmental agreements, such as the Agenda 2030, especially for water management in a peri-urban context. Here we present an innovative framework that can be applied to both NBS project planning and evaluation for several water-based challenges, giving practitioners and researchers a tool not only to evaluate ongoing projects but also to guide new ones. The framework considers three main stages of a NBS project: (1) context assessment, (2) NBS implementation and adaptation process, and (3) NBS results. This tool has the potential to be used to evaluate whether NBS projects are aligned with sustainability dimensions through a set of adaptable sustainability indicators. The framework can also highlight how the NBS targets are related to the sustainable development goals (SGDs) and contribute to catalyzing the 2030 Agenda. The framework is an important tool for water management and other NBS types.

Urban water management has recently been questioned because of the fragmented nature of the urban water system and its linear model. The integration and management of water systems are currently recognized as a socio-technical challenge that must be addressed for a more sustainable urban water management. In the short term, a key factor for its transition will be integration of alternative practices that allow for experimentation, learning, and scaling up. This study aims to identify potential shifts supported by two alternative practices for water reuse: nature-based solutions and water reuse technologies, using circular economy principles as analytical categories. The research uses a case study, the Besòs river of the Barcelona metropolitan area, to show that: i) improving biodiversity and water quality helps to regenerate natural capital; ii) water reuse for streamflow augmentation keeps resources in use and promotes synergies, which benefits social livability; and iii) risk management and a potential fit-to-purpose strategy can marginally help to avoid waste externalities. This research has shown that the CE principles are applicable as a framework for identifying the interconnected shifts promoted by water systems. A reflexive understanding of the alternative practices provides deeper insight into the experiences, barriers, and shifts that allow innovative interactions in specific urban contexts and can deliver additional benefits for society. This knowledge can be useful for integrated urban management; however, further integration of cross-sectoral collaboration and flexibility are required.

Nature-based solutions (NBS) are defined by the European Commission as "actions that are inspired by, supported by, or copied from nature..." and that solve societal challenges and multiple benefits. As a result, NBS are often promoted as alternative responses that solve complex societal challenges such as watershed management, while delivering a systemic approach of multiple benefits for well-being, human health, and sustainable use of resources. Despite rising interest in NBS, further identification of experiences implementing NBS could advance our understanding of the operationalization of this comprehensive concept. For this purpose, we analyzed 35 peer-reviewed articles on implementation experiences of NBS for water management in peri-urban areas, on aspects related to (i) NBS problem-solution: water challenges, ecosystem services, scales, and types; (ii) NBS governance and management. From the insights of the analysis, this paper asks what lessons are learned, and which barriers are identified, from implementing NBS for water management in peri-urban areas? As a result, this study presents a detailed analysis of each aspect. We conclude by highlighting accountancy, monitoring, and communication as potential success factors for integration and development while diminishing the overall barrier of complexity, which leads to technical, institutional, economic, and social uncertainty.