Chemical status

Distribution of chemical status of groundwater, rivers, lakes, transitional and coastal waters.

Note: Number of Member States contributing to the dataset: Groundwater (26); Rivers (25); Lakes (22); Transitional (15) and Coastal (20). Percentages shown for rivers, lakes, transitional and coastal are by water body count. Groundwater percentages, however, are expressed by area. The total number of water bodies is shown in parenthesis. Data from Sweden are excluded from surface water data illustrated in the figure. This is because Sweden contributed a disproportionately large amount of data and, classified all its surface waters as poor status since levels of mercury found within biota in both fresh and coastal waters exceed quality standards.

Data source:

• WISE WFD Database provided by  Directorate-General for Environment (DG ENV)

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Hazardous substances in fresh and marine water can harm aquatic life and pose a risk to human health. Hazardous substances can have detrimental effects on aquatic biota. For example, substances with endocrine-disrupting properties can impair reproduction in fish and shellfish, while the effects of organochlorines on marine life are well documented, as is the toxicity of metals and pesticides to freshwater biota. Such impacts diminish the services provided by aquatic ecosystems, including the provision of food.

The chemical status of surface waters is assessed for compliance with environmental standards on substances that are listed in the WFD (Annex X) and the Environmental Quality Standards (EQS) Directive 2008/105/EC. These priority and priority hazardous substances include metals, pesticides and various industrial chemicals. The Groundwater Directive establishes a regime to assess groundwater chemical status, providing EU-wide quality standards for nitrate and pesticides, and requiring standards to be set at national level for a range of pollutants. 

The chemical status of more than 13 000 groundwater bodies has been reported across Europe, encompassing 26 different Member States (Figure 1). Good chemical status is apparent in 72 % of them (by surface area) whilst about 25 % are in poor status. Approximately 3 % of groundwater bodies are classified as having unknown chemical status. 60 % of instances of poor chemical status are accounted for by an exceedance of a quality standard (threshold value) for one or more pollutants. Other important causal factors include the deterioration in quality of waters for human consumption and saline intrusion.

The chemical status of 123 000 surface freshwater bodies (104 000 rivers and 19 000 lakes) has been evaluated across 26 Member States across Europe, with 43 % of rivers and 44 % of lakes (by count) being classified as good, and 6 % and 2 % respectively being in poor status. However, these overall statistics do not include the results from Sweden (see note to Figure 1).

Notably, the chemical status of 51 % of the rivers and 54 % of the lakes remains unknown. The main reasons for the high percentage of surface water bodies with reported unknown chemical status are that the status assessment methods have not yet been fully developed, or that there were not enough monitoring data in this first RBMP cycle.

Proportion of classified groundwater bodies in different River Basin Districts in poor chemical status

Note: The figure shows percentage of the total area of classified water bodies. See the indicator specification for more details

Data source:

• WISE WFD Database provided by  Directorate-General for Environment (DG ENV)

Downloads and more info

Proportion of classified surface water bodies in different River Basin Districts in poor chemical status for rivers and lakes (left panel) and for coastal and transitional waters (right panel)

Note: The figure shows percentage of the total number of classified water bodies. See the indicator specification for more details.

Data source:

• WISE WFD Database provided by  Directorate-General for Environment (DG ENV)

Downloads and more info

Chemical status of groundwater (Fig. 2)

The chemical status of more than 13 000 groundwater bodies has been reported across Europe, encompassing 26 different Member States (Figure 1). Good chemical status is apparent in 72 % of them (by surface area) whilst about 25 % are in poor status. Approximately 3 % of groundwater bodies are classified as having unknown chemical status. 

A total of 16 Member States have more than 10 % of groundwater bodies in poor chemical status (by area), whilst this figure exceeds 50 % in Luxembourg, the Czech Republic, Belgium (Flanders) and Malta. A high proportion of the groundwater bodies holding poor chemical status are found in the RBDs in central north-western Europe (Figure 2), with many RBDs in the region having more than half of groundwater bodies in poor chemical status.

Excessive levels of nitrate are the most frequent cause of poor groundwater status across much of Europe. Agriculture is the primary source of this nitrate, deriving from the input of mineral and organic fertilisers and subsequent leaching to groundwater. Pesticides and a range of other chemicals such as heavy metals are also causes of poor groundwater status across Europe. The threshold values to assess groundwater chemical status vary markedly between Member States for certain pollutants.

Chemical status of rivers and lakes (Fig. 3 left)

The chemical status of 123 000 surface freshwater bodies (104 000 rivers and 19 000 lakes) has been evaluated across 26 Member States across Europe, with 43 % of rivers and 44 % of lakes (by count) being classified as good, and 6 % and 2 % respectively being in poor status. However, these overall statistics do not include the results from Sweden.

Notably, the chemical status of 51 % of the rivers and 54 % of the lakes remains unknown. The main reasons for the high percentage of surface water bodies with reported unknown chemical status are that the status assessment methods have not yet been fully developed, or that there were not enough monitoring data in this first RBMP cycle.

A total of 10 Member States report poor chemical status in more than 20 % of their rivers and lakes, whilst in Hungary, Belgium (Flanders), Denmark, and Poland, this figure rises to above 40 %, reaching 100 % in Sweden (Figure 5.3). These figures exclude the many rivers and lakes across Europe with an unknown chemical status; unknown status exceeds 50 % in 10 countries and 20 % in all but 11 countries. 

Excluding data for Sweden (to avoid distortion of results) indicates that the ‘other pollutants’ group is the most frequent overall cause of poor status in rivers. 18 Member States identified this group as problematic, particularly in Belgium (Flanders), Germany, France and the United Kingdom. A substantial number of rivers also fail to reach good status due to this pollutant group in the Czech Republic, the Netherlands and Romania. Within the ‘other pollutant’ grouping, PAHs are identified as problematic by 11 Member States including most of the RBDs in France, all British RBDs except for those in Scotland, the Belgian Scheldt and the Czech and German parts of the Elbe. PAHs result from incomplete combustion processes, and are subject to long-range transport in the atmosphere. As a result, subsequent deposition and adverse impacts upon aquatic environments may occur a great distance from the original point of emission.

Chemical status of transitional and coastal waters (Fig. 3 right)

Chemical status for more than 4 000 transitional and coastal water bodies has been reported across 16 and 21 Member States respectively. Poor chemical status is reported in 10 % of transitional and 4 % of coastal water bodies, whilst good status is reported in 35 % and 51 %, respectively. The amount of ‘unknown’ status water bodies reported is notable: 55 % of transitional and 46 % of coastal water bodies are classified in this category.

Six Member States (France, Germany, Belgium (Flanders), Sweden, Romania and the Netherlands) report poor chemical status in transitional waters (excluding those of unknown status) to be 50 % or more. ‘Other pollutants’ are the most frequent cause of poor chemical status in transitional waters across Europe, and they are the most frequent cause of poor status within Belgium (Flanders), Germany, France, the Netherlands and the United Kingdom. TBT is one of those ‘other pollutants’ identified as problematic. It is the main cause of poor status in transitional waters in six RBDs of the United Kingdom, and is a contributing factor elsewhere, including the Belgian-Scheldt, the Nemunas in Lithuania, the north and south Baltic RBDs of Sweden, and the Loire in France. PAHs contribute to poor status in transitional waters in Romania, France and Belgium.

Heavy metals are the most frequently reported cause of poor chemical status in Swedish and Spanish transitional waters. In the case of Spanish waters, heavy metal pollution is linked to mining discharges. Mercury is a cause of poor status in some Swedish transitional waters, although the problem is not as widespread as for Swedish freshwaters. In France, heavy metals cause poor status in transitional waters of the Rhône, Loire and Seine RBDs. Heavy metals are also problematic in the northern Apennines RBD in Italy and in the Romanian Danube.

Some industrial pollutants are also identified as a cause of poor chemical status in transitional waters. DEHP, for example, is a cause of poor status in the Rhône and Loire RBDs in France and the Nemunas RBD in Lithuania, whilst nonylphenol is identified as problematic in transitional waters of Portugal and Belgium. In Irish transitional waters, brominated diphenyl ether causes poor chemical status.

Transitional waters with the poorest chemical quality across Europe are typically those subject to pollution from a range of individual pollutants. For example, the Seine in France reports heavy metals, pesticides and PAHs to be an issue, whilst in the Belgian-Scheldt, 12 chemicals including mercury, pesticides, PAHs, TBT and the industrial chemical nonylphenol are all a cause of poor status. Similarly, the Romanian part of the Danube RBD is polluted by the heavy metals cadmium, lead and nickel, as well as by a range of PAHs and some pesticides.