Regulatory obstacles to aquifer resilience: A comparative legal-policy analysis of hydrogeological connectivity and managed aquifer recharge governance in Europe

This article examines whether existing regulatory frameworks support or hinder aquifer resilience in the context of Managed Aquifer Recharge (MAR), with particular focus on the use of rainwater and stormwater as potential source water for recharge. It addresses a key knowledge gap at the interface of hydrology and law: the limited integration of hydrological connectivity into legal and policy frameworks governing groundwater systems. The study adopts a two-step interdisciplinary approach. First, it draws on hydrological and resilience literature to establish that aquifer resilience depends not only on the regulation of groundwater abstraction but also on the governance of recharge processes. Second, it undertakes a comparative legal-policy analysis of four European jurisdictions —the Netherlands, Ireland, Spain, and Hungary—to assess how existing regulatory systems recognise, support, or constrain these processes. The analysis reveals a consistent pattern of regulatory fragmentation. Groundwater, surface water, and rainwater are frequently governed through separate legal regimes “silos”, institutional structures, and policy objectives that fail to reflect the interconnected nature of the hydrological cycle. As a result, rainwater and stormwater— remain weakly integrated into groundwater governance and are often managed under priorities that favour rapid drainage rather than infiltration and recharge. The study therefore argues that integrated, science-informed governance aligned with the “One Water” paradigm is critical for strengthening aquifer and enabling the wider application of MAR, under conditions of climate change.