Hydrological variability has been on the rise in the past decades with dramatic consequences for water management on the national and international plane alike. Yet, most legal regimes governing the use and protection of water resources reflect a high degree of rigidity presuming that hydrological conditions prevailing at the time of their conception remain stable indefinitely. The mismatch between rigid legal frameworks and rapidly changing natural conditions are likely to give rise to new types of interstate conflicts in shared river basins (or accentuate existing ones), since historically the adoption of (new) transboundary governance regimes has been very slow and reactive in character. While the EU has been praised worldwide as an exemplary model of co-riparian cooperation, its multi-layered water governance regime also deserves a comprehensive fitness check that, among others, should evaluate its ability to handle the growing uncertainty surrounding underlying hydrological circumstances. This article provides a resilience assessment of European water law from the perspective of the management of hydrological variability.