Brussels-Capital Region: piezometric maps (May 2013) for the following aquifer (and aquitard) hydrogeological units : - UH/RBC_1 Quaternary aquifer system: US/RBC_14 Silts, sands and alluvial gravels ; - UH/RBC_2 Perched sandy aquifer system (Diest Fm, Bolderberg Fm, Sint-Huibrechts-Hern Fm and Onderdale Member); - UH/RBC_4 Aquifer system of the Wemmel, Lede, Brussels and Vlierzele sands (or better known as the Bruxellian sands); - UH/RBC_6 Aquitard of Tielt sands and clays ; - UH/RBC_7 Kortrijk Sand and Clay Aquitard System (Moen Member); - UH/RBC_8 Aquifer of the Landénien sands. The piezometric levels (in m-DNG/TAW) are represented by piezometric lines separated by a 2m step. These data are limited to the borders of the Brussels-Capital Region extended by a 500m buffer zone. The piezometric maps of UH/RBC 1 to 7 are from Brussels Phreatic System Model v1.0 (BPSM v1.0) and that of UH/RBC 8 is from Hydroland v1.0. These two hydrogeological models were developed under FEFLOW 7.1 and 6.1 ® respectively. del. This data is generated from models and may contain errors, inaccuracies and gaps. It has informative value and may under no circumstances replace a study carried out by an expert. Bruxelles Environnement cannot be held liable for the consequences of the use of this information.

Brussels-Capital Region : The geological model BRUSTRATI3D v1.1 is a set of raster files covering the Brussels-Capital Region. These files contain the roof elevations and the thicknesses of the Stratigraphic Units (SU/BCR) and the Digital Terrain Model (DTM) of the topographic surface used in this model. These rasters have a 10x10m resolution and their reference coordinate system is EPSG 31370 (Belgian Lambert 31370). The documentation relating to the construction oh these data is available at the following addresses (French only): BRUSTRATI3D v1.1 https://document.environnement.brussels/opac_css/index.php?lvl=notice_display&id=10965 BRUSTRATI3D v1.0 https://document.environnement.brussels/opac_css/index.php?lvl=notice_display&id=10964 As the data in this archive is model-based, it may contain errors, inaccuracies and gaps. They should be used with caution and critical thinking. They can in no way replace a field study carried out by an expert. In general, Brussels Environment and the Geological Survey of Belgium cannot, under any circumstances, be held responsible for any damage, direct or indirect, resulting from the use of these data or the impossibility of using them for any reason whatsoever.

This map indicates the impervious surfaces where rainwater cannot or hardly infiltrate into the soil for the year 2022. Impervious surfaces are: artificial sealed surfaces (such as streets, squares, car parks ...), buildings and compact soils. Permeable surfaces are vegetation-covered soils, bare soils and water areas. Railway areas are permeable or impermeable depending on the type of cover. The map was compiled from satellite images (Sentinel -2) and orthophotos (from UrbIS and Digitaal Vlaanderen) with a final resolution of 1m.

Brussels-Capital Region : the localization of the culvert rivers in the Brussels Region. Includes additional information: the name and type (culvers river, sewer, ...) of the hydrological segment.

Brussels-Capital Region: The nitrate-vulnerable zone is a protected area against the pollution of groundwaters caused by nitrates from agricultural sources. It was designated in accordance with the prescriptions of the European Directive 91/676/EEC, by the Ministerial Order of 25 May 1999.

Brussels-Capital Region: Map of the absolute piezometric phreatic levels (May 2013) obtained with the combination of the piezometric levels of the following hydrogeological units of the Brussels phreatic system: - UH/RBC_1 Quaternary aquifer system: US/RBC_14 Silts, sands and alluvial gravels ; - UH/RBC_2 Perched sandy aquifer system (Diest Fm, Bolderberg Fm, Sint-Huibrechts-Hern Fm and Onderdale Member); - UH/RBC_4 Aquifer system of the Wemmel, Lede, Brussels and Vlierzele sands (or better known as the Bruxellian sands); - UH/RBC_6 Aquitard of Tielt sands and clays ; - UH/RBC_7 Kortrijk Sand and Clay Aquitard System (Moen Member); This map thus includes the absolute piezometric levels of the most superficial aquifer units, in order to map the level of the "piezometric groundwater surface". The piezometric levels (in m-DNG/TAW) are represented by level lines (isopiezes) separated by a 2m step. These data are limited to the borders of the Brussels-Capital Region extended by a 500m buffer zone. These data are extracted from the Brussels Phreatic System Model v1.0 (BPSM v1.0) hydrogeological model, developed under FEFLOW 7.1 ®. This data is generated from models and may contain errors, inaccuracies and gaps. It has informative value and may under no circumstances replace a study carried out by an expert. Bruxelles Environnement cannot be held liable for the consequences of the use of this information.

Brussels-Capital Region: map of the depth of the piezometric phreatic levels (May 2013) obtained with the combination of the piezometric levels of the following hydrogeological units of the Brussels phreatic system: - UH/RBC_1 Quaternary aquifer system: US/RBC_14 Silts, sands and alluvial gravels ; - UH/RBC_2 Perched sandy aquifer system (Diest Fm, Bolderberg Fm, Sint-Huibrechts-Hern Fm and Onderdale Member); - UH/RBC_4 Aquifer system of the Wemmel, Lede, Brussels and Vlierzele sands (or better known as the Bruxellian sands); - UH/RBC_6 Aquitard of Tielt sands and clays ; - UH/RBC_7 Kortrijk Sand and Clay Aquitard System (Moen Member); This map thus includes the relative piezometric levels of the most superficial aquifer units, in order to map the depth of the "piezometric groundwater surface". The piezometric levels (in metres from the topography) are represented by level lines (isobaths) separated by a 2m step. These data are limited to the borders of the Brussels-Capital Region extended by a 500m buffer zone. These data are extracted from the Brussels Phreatic System Model v1.0 (BPSM v1.0) hydrogeological model, developed under FEFLOW 7.1 ®. This data is generated from models and may contain errors, inaccuracies and gaps. It has informative value and may under no circumstances replace a study carried out by an expert. Bruxelles Environnement cannot be held liable for the consequences of the use of this information.

Brussels Capital Region: the location of the autorized groundwater abstraction in the Brussels Region. Both active permanent, temporary and old extraction. Contains also additional information: the date of authorisation, the annual extracted volume, the name of the aquifer and the depth (m) of the abstraction site.

Brussels-Capital Region : data on the 5 Groundwaterbody of the Area of Brussels, defined under the Directive and the Ordinance Water : code European, code of Brussels and name of the water mass, hydrographic district

Brussels-Capital Region: Monitoring network of the nitrate content in surface waters and groundwater. It was designated in accordance with the prescriptions of the European Directive 91/676/EEC concerning the protection of waters against pollution caused by nitrates from agricultural sources, by the Ministerial Order of 25 May 1999.