Dataset description: This dataset contains data on water flows, actual waterborne (riverine plus direct) inputs and atmospheric deposition of nutrients. Furthermore, it includes normalized total (atmospheric and waterborne) inputs of nitrogen and phosphorus into the Baltic Sea. The data are used in the HELCOM core indicator of nutrient inputs (nitrogen and phosphorus) to the Baltic Sea marine ecosystem (Inputs of nutrients - HELCOM indicators). The data is presented in the format of MS Excel workbook consisting of 3 sheets. Sheets of nitrogen inputs and phosphorus inputs integrate 4 tables each. These tables contain time series, starting from 1995, of assessed nutrient input values: waterborne actual (riverine+direct), atmospheric deposition (actual), total actual input (air+water), normalize total input (air+water). Nitrogen and phosphorus inputs are assessed for the following Baltic Sea sub-basins: Bothnian Bay (BOB), Bothnian Sea (BOS), Baltic Proper (BAP), the Gulf of Finland (GUF), the Gulf of Riga (GUR), Danish Straights (DS), Kattegat (KAT) and the whole Baltic Sea (BAS). All input data is given in tonnes per year (tonnes/year). The Flow sheet contains only one table with an annual water flow data time-series for each sub-basin of the Baltic Sea given in cubic meters per year (m3/s). The river input data is based on riverine monitoring data and estimation of loads from unmonitored areas by countries in the frame of national monitoring programs. Data on waterborne inputs and water flow is reported by Contracting Parties to the PLC-Water database. The data are verified and quality assured using the PLC water database verification tools and national expert quality assurance. Atmospheric deposition of nitrogen for all Baltic Sea sub-basins is computed using the latest version of EMEP MSC-W model and data on official emissions reported by EMEP Contracting Parties. Dataset content: Excel workbook contains the following sheets: Nitrogen inputs – time-series of waterborne actual (riverine+direct), atmospheric deposition (actual), total actual input (air+water), normalized total input (air+water) (tonnes/year) . Phosphorus inputs – time-series of waterborne actual (riverine+direct), atmospheric deposition (actual), total actual input (air+water), normalized total input (air+water) (tonnes/year). flow - annual water flow data time-series (m3/s). Visualization: MS Excel workbook. Data update: Metadata is updated by HELCOM Secretariat annually after adoption of indicator report. The dataset is updated by HELCOM Secretariat annually after adoption of indicator report.

Dataset description: This dataset displays spatial coverage of available data on riverine inputs of hazardous substances to the Baltic Sea. The data illustrates availability and where available contains values of annual average inputs of hazardous substances (the latest assessment period) from sub-catchments and coastal areas designated for the HELCOM PLC assessment. The sub-catchments are the smallest areas for which loads of nutrients and hazardous substances are assessed. Sub-catchments are always located within borders of a single country and drain into one Baltic Sea sub-basin. Sub-catchments may correspond to either monitored or unmonitored areas. Unmonitored sub-catchments may represent either unmonitored parts of river catchments or aggregated unmonitored areas (depending on the reporting format of each Contracting Party). The data is obtained through national monitoring programmes and annually reported by Contracting Parties to the HELCOM Pollution Load Compilation (PLC-water) database as an integral part of HELCOM Pollution Load Compilation process https://nest.su.se/helcom_plc/. However, the assessment of inputs and respective data updates are performed periodically in accordance with the workplan of respective PLC-projects. The data is produced, compiled and quality assured in accordance with the HELCOM Guidelines for the annual and periodical compilation and reporting of waterborne pollution inputs to the Baltic Sea (HELCOM PLC-Water Guideline). Dataset content: Polygonal feature class contains the following attributes: Source code (source_code): Unique code for river sub-catchments and unmonitored areas Source name (source_name): Name of river catchment or unmonitored area Sub-basin code (subb_code): Sub-basin of the Baltic Sea the sub-catchment drains to. Country code (c_code): The Country on which territory the river mouth is located, for border rivers both are mentioned. Area km2 (area_km2): Polygon area in sq.km. Cd_20XX: annual average input of cadmium in each year of the assessment period (tonnes/year) Cd_average: average input of cadmium in the assessment period (tonnes/year) Cr_20XX: annual average input of cadmium in each year of the assessment period (tonnes/year) Cr_average: average input of chromium in the assessment period (tonnes/year) Cu_20XX: annual average input of cadmium in each year of the assessment period (tonnes/year) Cu_average: average input of copper in the assessment period (tonnes/year) Hg_20XX:annual average input of cadmium in each year of the assessment period (tonnes/year) Hg_average: average input of mercury in the assessment period (tonnes/year) Ni_20XX: annual average input of cadmium in each year of the assessment period (tonnes/year) Ni_average: average input of nickel in the assessment period (tonnes/year) Pb_20XX: annual average input of cadmium in each year of the assessment period (tonnes/year) Pb_average: average input of lead in the assessment period (tonnes/year) Zn_20XX: annual average input of cadmium in each year of the assessment period (tonnes/year) Zn_average: average input of zinc in the assessment period (tonnes/year) Year: year of the assessment Visualization: The following maps visualize the data: Map of data coverage for zinc Map of data coverage for chromium Map of data coverage for copper Map of data coverage for nickel Map of data coverage for lead Map of data coverage for cadmium Map of data coverage for mercury Data update: Metadata is updated by HELCOM Secretariat periodically after adoption of PLC report on sources of nutrients. The dataset is updated by HELCOM Secretariat periodically after adoption of PLC report on sources of nutrients.