EU Sustainable Water Diplomacy: Security Challenges in EU External Relations Law

The imperative of water security (defined by the UN as ‘the capacity of a population to safeguard sustainable access to adequate quantities of acceptable quality water’) looms large in the quest for the European Union’s (EU) sustainable water management, both within its borders and beyond. As climate change continues, the EU faces growing threats to water security, stemming from increased freshwater variability, scarcity, and declining freshwater quality. This chapter delves into the largely uncharted territory of security considerations underpinning sustainable water management as they play out in EU external relations law. Of particular concern is in fact the international dimension of the water security challenge, necessitating cross-border cooperation with third-party nations. Tensions and conflicts in shared transboundary basins, lakes, and aquifers serve as stark reminders of the importance of cooperative approaches. The Chapter explores the security facets of freshwater and the legal instruments available to the EU to face them. To that aim, this Chapter undertakes an analysis of the interplay between water security and sustainability, especially focusing on the concepts of “conflicts” and “migration,” exemplified by situations in the Nile and Tigris-Euphrates basins. It delves into the complex web of EU external relations instruments, encompassing treaty law, secondary law, international law, and policy instruments, highlighting that the legal framework differs significantly depending on whether the situation falls partially within or entirely outside the EU's territorial boundaries. The Chapter concludes by emphasizing the critical role the EU must play in fostering resilience and cooperation in water governance, as climate change-induced unpredictability continues to reshape global water dynamics.