1.1. Contact organisation
Eurostat, the statistical office of the European Union
1.2. Contact organisation unit
E2: Environmental statistics and accounts; sustainable development
1.3. Contact name
Confidential because of GDPR
1.4. Contact person function
Confidential because of GDPR
1.5. Contact mail address
e-mail contact : ESTAT-SDG-MONITORING@ec.europa.eu
1.6. Contact email address
Confidential because of GDPR
1.7. Contact phone number
Confidential because of GDPR
1.8. Contact fax number
Confidential because of GDPR
2.1. Metadata last certified
20 January 2026
2.2. Metadata last posted
20 January 2026
2.3. Metadata last update
20 January 2026
The indicator is part of the EU Sustainable Development Goals (SDG) indicator set. It is used to monitor progress towards SDG 6 on clean water and sanitation, which is embedded in the European Commission’s 2024-2029 priorities under 'Sustaining our quality of life: Food security, water and nature'.
Among other things, SDG 6 calls for ensuring universal access to safe and affordable drinking water, sanitation and hygiene, and ending open defecation. It also aims at improving water quality and water-use efficiency and encouraging sustainable abstractions and supply of freshwater. SDG 2 seeks to end hunger and malnutrition, and ensure access to safe, nutritious and sufficient food.
This indicator can be considered as part of the global SDG indicator 6.3.2 "Proportion of bodies of water with good ambient water quality".
Protection of water resources, water ecosystems and of drinking and bathing water is at the cornerstone of EU environmental policy. EU water policy provides a framework to comprehensively address water protection and for achieving good status for inland surface waters, transitional waters, coastal waters and groundwater. According to the Drinking Water Directive, a maximum concentration of 50 mg/L of nitrate in groundwater that is used for drinking water is allowed. The Nitrates Directive requires the designation of vulnerable zones based on this threshold for all waters including groundwater.
The Water Framework Directive is the main European legislation aiming to prevent water pollution. The EU Biodiversity Strategy for 2030 supports the implementation of the Water Framework Directive’s objective by requiring Member States to restore freshwater ecosystems.
The 8th Environment Action Programme sets the environmental policy agenda for the years from 2021 to 2030 and explicitly mentions water-related issues in two of its six priority objectives. These two objectives are: (1) pursuing a zero-pollution ambition for a toxic free-environment, including for air, water and soil and protecting the health and well-being of citizens from environment-related risks and impacts; and (2) protecting, preserving and restoring biodiversity and enhancing natural capital, notably air, water, soil, and forest, freshwater, wetland and marine ecosystems.
4.1. Data description
This indicator shows concentrations of nitrate (NO3) in groundwater bodies measured as milligrams per litre (mg NO3/L). The indicator can be used to illustrate geographical variations in current concentrations and temporal trends. Large inputs of nitrogen to water bodies from urban areas, industry, and agricultural areas, can have negative impacts on the use of water for human consumption and other purposes.
Nitrate can persist in groundwater for a long time and accumulate at a high level through inputs from anthropogenic sources (mainly agriculture). The EU drinking water standard is limited to 50 mg NO3/L to avoid threats to human health. The distribution of measured groundwater bodies might mask exceedance of nitrate levels in certain polluted areas (see details on accuracy under point 4.4).
For time series analyses, only complete series after inter/extrapolation are used. As measuring stations change over time, this leads to a recalculation of the whole time series with each update. Complete series 2007 – 2023 are based on a total of 2166 groundwater bodies (2104 within 22 EU Member States). These groundwater bodies are distributed over the following countries (number of groundwater bodies in parentheses): Belgium (52), Bulgaria (65), Czechia (157), Denmark (8), Germany (413), Estonia (21), Ireland (95), Spain (226), France (522), Italy (176), Cyprus (22), Latvia (14), Lithuania (17), Netherlands (15), Austria (17), Poland (47), Portugal (72), Romania (25), Slovenia (6), Slovakia (73), Finland (27), Sweden (34) Switzerland (39) and Serbia (23).
The aggregate for EU_V includes data for 22 EU Member States (Belgium, Bulgaria, Czechia, Denmark, Germany, Estonia, Ireland, Spain, France, Italy, Cyprus, Latvia, Lithuania, Netherlands, Austria, Poland, Portugal, Romania, Slovenia, Slovakia, Finland and Sweden).
4.2. Unit of measure
mg NO3 per litre.
4.3. Reference Period
Calendar year.
4.4. Accuracy - overall
The time series on nitrate in groundwater is considered robust for long-term trends due to extensive quality control and consistent methodology using generalized additive models (GAM) for data gap-filling.
Precision is impacted by variations in national data reporting and water body delineation (spatial data).
The time series are based on data collection methods and aggregation techniques, which include using annual averages that may not capture extreme events, varying sampling frequencies, data set gaps filled by inter/extrapolation, and changes in monitoring sites requiring recalculation.
4.5. Source data
4.5.1. Source data - Organisation
EEA (Waterbase database)
4.5.2. Source data - Comment
Data source: EEA Waterbase database on Water Quality ICM
Data provider: European Environment Agency (EEA)
5.1. Frequency of dissemination
5.1.1. Frequency of dissemination - Grade
Every year5.1.2. Frequency of dissemination - Comment
The indicator is updated annually.
5.2. Timeliness
5.2.1. Timeliness - Grade
T+2 years5.2.2. Timeliness - Comment
New data points are disseminated within two years after the reference year.
6.1. Reference area
6.1.1. Reference Area - Grade
> 75% EU MS and EU aggregate6.1.2. Reference Area - Comment
Data are presented for all EU Member States except Greece, Croatia, Luxembourg, Hungary and Malta.
6.2. Comparability - geographical
6.2.1. Comparability - geographical - Grade
> 75% EU MS6.2.2. Comparability - geographical - Comment
Data comparability between EU Member States, respectively other presented countries, is limited due to monitoring programs, including methodology and spatio-temporal sampling density, varying from country to country. The reporting is voluntary so countries do not necessarily report all available data.
6.3. Coverage - Time
6.3.1. Time Coverage - Grade
> 10 years6.3.2. Time Coverage - Comment
Presented time series (aggregate changing according to the context EU_V) starts in 2007.
6.4. Comparability - over time
6.4.1. Comparability - over time - Grade
> 4 data points6.4.2. Comparability - over time - Comment
Length of comparable time series without methodological break is longer than 4 data points.
7.1. Dissemination format - Publications
Analysis of indicator is presented in Eurostat's annual monitoring report on Sustainable development in the EU (progress towards SDGs in an EU context).
7.2. Dissemination format - online database
See table sdg_06_40
7.3. Dissemination format - other
Eurostat dedicated section on SDGs: Eurostat overview.
Copyrights: Eurostat Copyright/Licence Policy is applicable.
