During the three first months of the AQUATERRA project, the Group of Hydrogeology and Environmental Geology from the University of Liège (HGULg) has performed a general inventory of data sources and availability for the Walloon part of the Meuse basin in Belgium. This deliverable provides the information in the form of a summary table that gives a general description of data types, accessibility (public or confidential, free or charged…) and, if existing, a website with further useful information. In this synthesis, emphasis is put on hydrogeological information. However, general information on surface water is also provided when available. In the following months, needed data will be collected for the Meuse/Basin experimental sites in the Walloon region. Collected datasets will be introduced into the Hydrogeological Database HYGES developed by HGULg. This database is presently updated for the needs of the AQUATERRA Project. This synthesis will be further updated when new information and data sources are available. ; AquaTerra - Integrated Modelling of the river-sediment-soil-groundwater system; advanced tools for the management of catchment areas and river basins in the context of global change