Managed Aquifer Recharge in Wallonia (Belgium) The MARWAL Project

Among all effects induced by climate change, the increasing occurrence of extreme hydrological events is of particular concern in some regions of the world. Specifically, the repetition of summer and winter droughts these last years have caused a diminution of groundwater levels in the major aquifers of Belgium and significant reductions of base flows. Such observations reflect a decrease in natural infiltration of meteoric waters and an increase in groundwater withdrawals, especially to meet agricultural water needs.
Public authorities of the Walloon Region of Belgium have implemented a Regional Water Resources Management Plan aimed at implementing a series of actions and measures to secure drinking water supply and protect water resources. In this context, the MARWAL project consists of a feasibility and pilot study to assess to what extent Managed Aquifer Recharge (MAR) constitutes an appropriate response to securing Wallonia's groundwater resources both from a technical, financial, and regulatory perspective.
In a first step, international benchmarking has been carried out to identify managed aquifer recharge systems most frequently implemented in environmental contexts similar to those met in Wallonia. On the basis of this information, a cartography of the potential for managed aquifer recharge has been established, mainly by cross-referencing geological contexts, available sources for recharge water and the strategic status of a number of priority catchment areas.
The second part of the study aims to precisely assess the MAR potential in the Hesbaye chalk aquifer in the Liège region, with a view to setting up a first pilot project. This phase of the investigation is based on a more detailed analysis of land use and hydrogeological conditions prevailing in the groundwater basin and advanced characterisation of available water sources from both a quantitative and qualitative point of view.
The objective is to present the project and results obtained so far.