The national wastewater-based epidemiological surveillance of psychoactive substances monitors the presence of various psychoactive substances in several wastewater treatment plants across Belgium. This dataset contains the results per treatment plant since the beginning of the surveillance in 2025. The results consist of the psychoactive substances concentrations over time as well as other data needed for the interpretations such as the flow rates of the treatment plants and the population covered.

The Royal Decree of 22 May 2019 establishing a marine spatial plan defines 6 measuring poles: Measuring pole MOW.0 (Art. 21§2), Measuring pole MOW.1 (Art. 21§2), Measuring pole MOW.2 (Art. 21§2), Measuring pole MOW.3 (Art. 21§2), Measuring pole MOW.4 (Art. 21§2), Measuring pole Westhinder (Art. 21§2). It replaces the 2014 Marine Spatial Plan, which is included for completeness. The Royal Decree of 20 March 2014 establishing a marine spatial plan defines in its Art. 15. §3, one set of measuring pole locations. These locations are made available digitally in the resource described by this metadata document. Please refer to the Belgian official gazette (\"Moniteur belge/Belgisch Staatsblad\") for official reference information.

Since August 2019, users of the RMI smartphone app are able to send an observation of the meteorological conditions at a certain place and a certain time. The observations provide information about the weather conditions and potentially severe weather to the other users and to RMI. The collection of citizen weather reports is a valuable complement to the information obtained with the classical instruments like stations, radar and satellite. The data can be exploited for nowcasting, warnings and model verification, and eventually in assimilation. A general introduction of the data and their characteristics can be found in Reyniers et al. (2023). A basic quality control is implemented on the received observations via a plausibility check. This plausibility check determines whether an observation is plausible, suspicious or false, by comparing it to the INCA-BE nowcasting system using a simple thresholding scheme. INCA-BE is RMI's operational nowcasting system described in Reyniers et al. (2021). There is no strict spatial extent since there is no restriction at the input side: users can send observations from all over the globe. The bulk of the observations are received from within Belgium. Note that the plausibility check is not available for reports from outside Belgium.

The number of inhabitants on January 1 according to the official definition of the population, by administrative entity (region, province, district and municipality) for Wallonia.

The localised unemployment rate calibrated on the labour force survey (LFS), by administrative unit (region, province, district and municipality) for Belgium.

The INSPIRE contour lines used for a cartographic representation of the relief at scale 1:50000, a product of the National Geographic Institute in Belgium. The dataset features are in accordance with the INSPIRE specifications.

Electricity network is the INSPIRE vector data set originated from the High-Tension network of the product TOP10Vector of the National Geographic Institute in Belgium. The Electricity network is regularly updated with the ELIA Group data sources. It includes the "ElectricityCable" features and the "Pole" features in accordance with the INSPIRE specifications.

UNDER EMBARGO - This dataset contains marine organic matter source samples, artificial mixtures of known composition, and compound-specific nitrogen stable isotope data of amino acids (δ¹⁵N-AA). Source materials include phytoplankton, zooplankton, and faecal pellets from the marine fouling species Mytilus edulis and Metridium senile.Samples were collected and processed in the laboratory under controlled conditions. Artificial mixtures were prepared by combining source materials in defined proportions to generate experimental samples representing multiple marine organic matter source combinations. Metadata describing sample collection, preparation, and mixture composition are included.Compound-specific nitrogen isotope ratios of individual amino acids were measured using stable isotope analysis. The dataset includes isotopic measurements for all source samples and artificial mixtures, along with associated metadata required to document sampling, laboratory preparation, and analytical procedures.

The law of 13 June 1969 defines “Belgian Continental Shelf” as follows: the seabed and the subsoil of the marine areas adjacent to the Belgian coast but beyond the Belgian territorial sea.

The Geological Map of Belgium at a scale of 1:40000 is published by the Belgian Geological Survey.