Study on the controlled recharge of aquifers: Wallonia anticipates drought episodes
The MARWAL project - Managed Aquifer Recharge for the aquifers of WALlonia - designed by the Service Public de Wallonie (SPW) and implemented by the Université de Liège (UEE/ School of Engineering) - aims to analyse the feasibility of setting up controlled groundwater recharge systems for future use (temporary storage).
W
hile the state of water resources in Wallonia does not currently give cause for particular concern, the medium- and long-term consequences of repeated summer and winter droughts as a result of climate change must be anticipated. In order to guarantee satisfactory groundwater levels, several courses of action are being considered in Wallonia, including the technique of controlled groundwater (aquifer) recharge. This has just been the subject of an agreement between the SPGE (Société Publique de Gestion de l'Eau), the SWDE (Société Wallonne des Eaux) and the University of Liège to set up the MARWAL (Recharge Maîtrisée des Aquifères de Wallonie) project.
Developed on the initiative of the Walloon Public Service, the MARWAL project is funded to the tune of EUR 500,000 as part of the implementation of the Walloon Recovery Plan (PRW). It is also part of the Regional Water Resources Plan (SRRE2.0) and the Water value chain of the Circular Wallonia strategy. Its first aim is to carry out a Walloon-wide analysis to assess the relevance and feasibility of controlled aquifer recharge (also known as artificial recharge) based on existing data. In a second phase, a controlled aquifer recharge system will be the subject of a technical feasibility study for the Hesbaye chalk aquifer (the largest drinking water reserve in the Liège region).
Controlled exploration of aquifers involves the controlled introduction of water into a water table to increase its natural recharge for later use (temporary storage) or for environmental benefit, for example to support the flow of a river during low-water periods, when the river's flow is at its minimum, fed solely by groundwater drainage. The water introduced may come from rainwater, treated wastewater or surface water. The water is introduced either via infiltration basins or via injection and pumping wells in the water table. The technique of controlled aquifer recharge requires rigorous planning and management to guarantee water quality.
The MARWAL project has been entrusted to the ULiège Hydrogeology and Environmental Geology research group, in partnership with CEBEDEAU, AIDE, CILE and the Raisô and Geolys consultancies.
