Adaptation Challenges in Complex Rivers Around the World: The Guadiana and the Colorado Basins

摘要

Integrated water resources management provides an often-recommended governance framework to manage water resources in a sustainable way. The application of this framework on Transboundary Rivers brings additional challenges, which can be exacerbated due to climate changes and extremes (such as droughts). These changes affect the operation of water infrastructures and will affect water management practices. Thus, the understanding and development of adaptation measures (across socio-economic, environmental and administrative systems) are critical, mainly on drought prone transboundary river basins. The paper draws on research conducted to 1) assess climatic risks in those watersheds, 2) describe the challenges in water resources management in the context of climate change, and 3) draw lessons for improving the use of research-based information. Two case studies were selected, the Colorado River Basin (North America) and the Guadiana River (Iberian Peninsula), the latter of which in the context of the five river basins shared between Portugal and Spain. Research and experience in these Basins show that several paradoxes in multistate water management and governance across borders militate against the accurate assessment of socio-economic impacts and the effective use of scientific information for meeting short-term needs in reducing longer-term vulnerabilities. Lessons drawn from both studies, but not always learned in practice, abound. These lessons include an expanded use of incentives for improving collaboration, water-use efficiency, demand management and for the development of climate services to inform water-related management as new threats arise. Recommendations are established for more effectively linking risk assessment approaches with resilience strategies that are applicable in practice and available to decision makers in a changing climate.