5.     European overview of ecological status, pressures and impacts

5.1.     Key messages

• More than half of the surface water bodies in Europe are reported to be in less than good ecological status or potential, and will need mitigation measures to meet the WFD objective.
• River water bodies and transitional waters are reported to have worse ecological status or potential and more pressures and impacts than water bodies in lakes and coastal waters.
• The pressures reported to affect most surface water bodies are pollution from diffuse sources causing nutrient enrichment, and hydromorphological pressures causing altered habitats.
• The worst areas of Europe concerning ecological status and pressures in freshwater are in Central Europe, in particular in Northern Germany, the Netherlands and Belgium, while for coastal and transitional waters the Baltic Sea and Greater North Sea regions are the worst.

Figure 5.0. Proportion of classified water bodies in less than good ecological status or potential, with pressures and with impacts in different water categories.

Notes: For pressures and impacts, the percentage is calculated against the total number of classified surface water bodies in countries reporting pressures or impacts. Swedish surface water bodies where the pressure or impact reporting is considered only to be related to airborne mercury contamination are defined as not affected (see text). See appendix for further details.

5.2.     Ecological status or potential for different water categories

Overall, more than half (55 %) of the total number of classified surface water bodies in Europe are reported to have less than good ecological status/potential. All these water bodies thereby need management measures to restore their ecological status or potential to fulfil the WFD objective. A higher proportion of water bodies with moderate or worse ecological status/potential is reported for rivers and transitional waters (60-70%) than for lakes and coastal waters (40-50%) (Figure 5.1).

Figure 5.1 Distribution of ecological status or potential of classified rivers, lakes, coastal and transitional waters, calculated as percentage of the total number of classified water bodies (upper panel: number given in brackets)or total length (classified rivers) or surface area (classified lakes, coastal and transitional waters) (lower panel: length or surface area given in brackets).

Notes: See chapter 3 for methodology used for assessing ecological status or potential and appendix notes for figure 5.0 on countries reporting and water bodies classified. For length/area issues see appendix notes.

For rivers, ca. 44000 water bodies (58% of the total number), or ca. 606 000 km (65% of total river length) are reported to have less than good ecological status or potential. For lakes, almost 6000 lake water bodies (43% of total number) or close to 31 000 km² (39% of total surface area) are reported to be in less than good ecological status or potential. The reason why lakes are better than rivers is probably related to the large proportion of lakes in Sweden and Finland, where the population density is low and there are large natural areas (boreal forests). The rivers are more evenly distributed throughout Europe with a larger proportion of rivers in densely populated and cultivated areas in Central Europe. However, also within countries lakes are generally reported to have better status than rivers (see chapter 4).

The worst water category is transitional waters, where 69% of the total number or 85% of the total surface area is reported to be in less than good ecological status/potential. In coastal waters, the situation is somewhat better with 48% of total number or 43% of total surface area reported to be in less than good ecological status or potential. The reason why transitional waters are so much worse than coastal waters is probably related to the smaller volume of water in transitional waters, as well as their proximity to pollution sources being located at the mouth of rivers with high pollution loads. Moreover, transitional waters are exposed to extensive hydromorphological pressures caused by land reclamation, flood protection, as well as large harbours causing altered habitats in these water bodies.

Rivers and transitional waters are both worse as proportion of length or area than as proportion of total number (comparing the upper and lower panels of figure 5.1 for each water category), whereas for lakes and coastal waters the picture is opposite. This means that for lakes and coastal waters the large water bodies are generally in better status than the smaller ones, whereas the largest rivers and transitional water bodies are in worse status than the smaller ones. The reason for this difference may be that the largest lakes and coastal waters have larger volumes of water and thus dilute the pollution to a larger extent than smaller water bodies, whereas large rivers and transitional waters are subject to more uses and are often located in areas with more pressures than the smaller ones.

 The basis for assessing ecological status or potential of water bodies in the first RBMPs is quite weak in some countries, causing uncertainty in the results described below. The comparability across countries and RBDs is therefore limited. Further details on the basis of the assessment done by the different Member States are outlined in chapter 3 above.  The main differences in ecological status or potential between MSs / RBDs shown in figure 5.2 below may still reflect the general situation in Europe, although some of the details may be wrong. 

5.3.     Ecological status or potential in different river basin districts

The worst ecological status or potential in river and lake water bodies are reported in River Basin Districts in Northern Germany, the Netherlands and Belgium (Flanders), where more than 90% are reported to be in less than good ecological status/potential (Figure 5.2, see also chapter 4 for country specific results). Other problem areas are in Poland, Southern Germany, Czech Republic, Southern England, Northern France, Hungary, as well as several single RBDs in other member states, where 70-90% of freshwater bodies are reported to be in less than good status/potential. The ecological conditions are reported to be slightly better in the southern part of Germany compared to the northern part, probably reflecting a combination of higher precipitation, less industry and more tourism (i.e. more interest in maintaining/restoring a natural landscape for the enjoyment of tourists), as well as lower population density and relatively less agricultural activity.  The map also illustrates the high variability in ecological conditions within single Member States, e.g. UK, Italy and Spain, and shows that even in the Member States with the best ecological conditions, there are regions that are less good (e.g. western Finland, south-eastern Sweden).

Figure 5.2 Proportion of classified surface water bodies in different River Basin Districts in less than good ecological status or potential for rivers and lakes (left panel) and for coastal and transitional waters (right panel) (percentage, based on number of classified water bodies).

Notes: Member states which have reported should indicate why classification of ecological status or potential is missing for certain RBDs, and if this information will be reported at a later stage.

For coastal and transitional waters, the worst areas where more than 90% of the water bodies are reported to have less than good ecological status are in the Baltic region (Southern Sweden, a part of the Finnish coast, Lithuania, Poland and Germany) and in the Greater North Sea region (north-western Germany, the Netherland, Belgium (Flanders) and south-eastern coast of UK). Also in the EU part of the Black Sea (RO, BG) the situation is poor with more than 70% of classified water bodies reported to be in less than good ecological status or potential.

The best ecological status or potential in coastal and transitional waters in Europe are found in Scotland and around the Mediterranean islands of Greece  and  Cyprus, as well as in the French part of the Bay of Biscay and in southern Italy, where more than 90% of the coastal and transitional water bodies are reported to be in good or better ecological status or potential. The results reported from the French Bay of Biscay and southern Italy are however quite uncertain, as the classified water bodies only constitute 20% and 2% of all the coastal water bodies in these two RBDs respectively (see also chapter 3 above). Another area with large numbers of water bodies in high and good status is the French coast of Brittany, the southern tip of Greece and most of the Spanish coast, including the Balearic islands.

5.4.     Main pressures and impacts affecting ecological status for all water categories

5.4.1.      Water bodies without pressures and impacts

In rivers and transitional waters, low proportions of water bodies are reported without significant pressures (figure 5.3), while somewhat higher proportions are reported to be without significant impacts.  For coastal waters, ca. half of the classified water bodies are reported to be without pressures and impacts.  A majority of lake water bodies are reported without significant pressures and impacts. This pattern is consistent with the differences found between the water categories for ecological status or potential (see section 5.2 above).

5.4.2.      Pollution pressures and water quality impacts

In general, rivers and transitional waters have more pollution pressures and water quality impacts than lakes and coastal waters, corresponding to the pattern found for ecological status/potential  (figure 5.1).

Pollution pressures from diffuse sources are reported for 30-40% of the classified water bodies in rivers and transitional waters, but only for ca. 20% of the classified water bodies in lakes and coastal waters (figure 5.3).  The relatively low proportion of water bodies reported with diffuse pressures is caused by the high number of water bodies in Sweden and Finland located in remote areas with low population density and only small areas of intensive agriculture.  The proportion of water bodies affected by diffuse source pollution would much higher if the water bodies affected by general diffuse pollution from Sweden were included, because all their water bodies are reported to be exposed to airborne pollution of contaminants, primarily mercury. The reason is that Sweden has used the biota standard for mercury of the new EQS directive to classify the chemical status of their water bodies, whereas other member states have used the “old” standards for mercury in water. Thus, in Sweden virtually all water bodies are in less than good chemical status due to mercury in fish. As this mercury pressure and impact may be less relevant for the ecological status, and also prevent the comparison of diffuse source pollution reported from other countries, it is important to show the picture without these data.

Point source pollution is reported as a significant pressure in more than 40% of classified water bodies in transitional waters, but is less important in the other water categories, due to improved urban waste water treatment during the past decades (more information in chapter 7 below).  The high proportion of point source pollution reported for transitional waters indicates that there are remaining challenges related to urban and industrial waste water in many estuaries in Europe.

The most important impacts of these pollution pressures is nutrient enrichment (figure 5.3).  In rivers as well as in transitional waters, there are almost similar proportions of water bodies exposed to diffuse source pollution as those affected by nutrient enrichment (ca. 30%).  In coastal waters more than 40% of the classified water bodies are reported to be affected by nutrient enrichment, which is twice as much as the proportion exposed to diffuse pollution.  This reasons for this discrepancy is unclear, but may be related to reporting mistakes or other unidentified pressures.  For lakes, less than 20% of the classified water bodies are reported to be affected by nutrient enrichment.  As for diffuse pollution this low proportion of lakes affected by nutrient enrichment is due to the high number of lakes found in the northern parts of Sweden and Finland.  Organic enrichment is reported to affect between 10-15% of all classified water bodies in rivers, lakes and coastal waters, but is more important in transitional waters, where the proportion of affected water bodies is close to 30%. The latter is consistent with the high proportion of transitional water bodies exposed to point source pollution.

 Figure 5.3. Percentage of total number of classified water bodies with identified significant pressures (left) and impacts (right) for a) rivers, b) lakes, c) coastal waters, d) transitional waters.

Rivers

Lakes

Coastal waters

Transitional waters

Notes:

The percentage is calculated against the total number of classified surface water bodies in member states reporting the specific pressure or impact type (or any pressure or impact for the blue bars). The number of member states included is indicated in brackets. “Hydromorphology” denotes the combination of the aggregated pressure types “Water flow regulations and morphological alterations of surface water“,“River management“,“Transitional and coastal water management“ and “Other morphological alterations“. A water body is defined as affected by any of the pressure types in the figures if it is reported with the aggregated pressure type and/or any of the corresponding disaggregated pressure types. The impact type “Contamination” means surface water bodies with the impact contamination by priority substances and/or contaminated sediment. Swedish surface water bodies where the pressure or impact reporting is considered only to be related to airborne mercury contamination are defined as not affected (see text). See appendix for further details. The impact type “Other impacts” menas surface water bodies with at least one of the impacts “Saline intrusion”, “Elevated temperatures” or “Other significant impacts”.

Acidification from long-range transported diffuse pollution are reported to affect ca. 10% of river water bodies and ca. 15% of lake water bodies in the few member states reporting this impact. Further information on acidification status and trends are included in chapter 7.

Contamination by priority substances and contaminated sediments are seemingly minor impacts in all water categories, affecting less than 20% of all classified water bodies, after excluding Sweden. The low percentage may be an artefact of the choices made by Member States on how to assess chemical status in the first river basin management plan in terms of chosen substances, standards (old vs. new EQS directive) and matrices (water or biota or sediment).  If other member states than just Sweden had also used biota standards of the new EQS directive, this impact would probably be larger. This would have implications primarily for chemical status classification, as most currently used assessment systems for ecological status classification are not sensitive to effects of hazardous substances.

5.4.3.      Hydromorphological pressures and altered habitats

Hydromorphological pressures and altered habitats are reported for a large proportion of classified water bodies in all the water categories, except in coastal waters, where these pressures and impacts are reported for a low proportion of classified water bodies (figure 5.3). The proportions of water bodies exposed to hydromorphological pressures are almost the same as those having altered habitats. In rivers and transitional waters these pressures and impacts are reported for ca. half of all classified water bodies, while in lakes ca. 30% of classified water bodies are affected.

Hydromorphological pressures and altered habitats are the most commonly occurring pressure and impact in rivers, lakes and transitional waters. However, as the numbers includes heavily modified and artificial water bodies, this pressure and impact is less important in natural water bodies. Moreover, hydromorphological pressures and altered habitats are sometimes affecting only a minor part of a water body (for example, physical shore-line alterations in lakes), and may thus have less serious ecological consequences than pollution pressures which often deteriorate the water quality of the whole water body. 

More information about hydromorphological pressures and altered habitats can be found in a separate thematic assessment report (EEA 2012 Hydromorphological alterations and pressures).

5.5.     Main pressures and impacts in different river basin districts

5.5.1.      Pollution pressures

Pollution pressures comprise all emissions to surface waters from point and diffuse sources, including nutrients, organic matter, acidifying substances and hazardous substances from local, regional or long-range transboundary pollution sources.

The highest pollution pressures in river and lake water bodies are reported in River Basin Districts in the Netherlands and Belgium (Flanders), as well as in southern Italy, south-eastern England, and smaller parts of northern Germany, where more than 90% of the water bodies are exposed to pollution pressures (chapter 4 for country specific results). Other problem areas are in the rest of Germany (except the two RBDs in the southeastern and southwestern part), Czech Republic, Southern England, Northern France, as well as several single RBDs in other member states, where 70-90% of freshwater bodies are reported to be exposed to pollution pressures.  The map also illustrates the high variability in pollution pressures within single Member States, e.g. UK, Italy and Spain, and shows that even in the Member States with low pollution pressures, there are regions that are have higher pollution pressures (e.g. western Finland, south-eastern Sweden).

Figure 5.4. Proportion of classified water bodies in different River Basin Districts affected by pollution pressures for rivers and lakes (left panel) and for coastal and transitional waters (right panel) (percentage, based on number of classified water bodies).

Notes: A water body is defined as affected by pollution pressures if it is reported with the aggregated pressure type “Point sources” and/or “Diffuse sources“ and/or any of the corresponding disaggregated pressure types. Swedish surface water bodies where the pressure reporting is considered only to be related to airborne mercury contamination are defined as not affected (see text). See appendix for further details. Member states which have reported pressures, but where certain RBDs are marked as “no data reported” should indicate whether this particular pressure has not been reported in this RBD or whether no water bodies in this RBD are affected by this particular pressure.

The general overview of pollution pressures reported for different RBDs (figure 5.4) is largely consistent with the results reported for ecological status or potential (figure 5.2). However, in some RBDs the ecological status or potential in rivers and lakes is worse than anticipated from the pollution pressures, such as in most of the RBDs in Sweden, the Baltic countries, Scotland, Poland, Austria and Hungary, as well as Brittany in France. The reason for this inconsistency is probably the impact of hydromorphological pressures (figure 5.5).

For coastal and transitional waters, the worst areas where more than 90% of water bodies are reported to be exposed to pollution pressures are in the Baltic region (Finland and Germany) and in the Greater North Sea region (north-western Germany, the Netherland and Belgium (Flanders)). Also along the coast of Brittany in France, most of the northern coast of Spain, both sides of northern Italy as well as in the Bulgarian part of the Black Sea, more than 70% of classified water bodies are reported to be exposed to pollution pressures.

The lowest proportion of coastal and transitional water bodies exposed to pollution pressures are reported from the west coast of Sweden, the north-eastern coast of Poland, as well as around the Greek  islands, where more than 90% of the coastal and transitional water bodies are reported to be without significant pollution pressures.

For coastal and transitional waters the consistency between the reported pollution pressures and the ecological status or potential is less clear. In some areas the ecological status or potential in these water categories is worse than what is suggested by the pollution pressures, e.g. in southern Sweden and Poland, which can be explained by hydromorphological or other pressures, as well as by pressures coming from outside the EU. However, in other areas the ecological status or potential is better than what is suggested by the pollution pressures, e.g. in Scotland, Brittany in France, northern coast of Spain and most of Italy. The reason can be that the pollution pressures are rapidly diluted in large, exposed coastal water bodies in these areas and therefore have less effect on their ecological status. However, also reporting mistakes and methodological artifacts may contribute to these inconsistencies.  

5.5.2.      Hydromorphological  pressures

Hydromorphological pressures comprise all physical alterations of water bodies modifying their shores, riparian/littoral zones, water level  and flow, (except water abstraction). Examples of such pressures are damming, embankment, channelization, non-natural water level fluctuations.

The hydromorphological pressures in rivers and lakes are reported to be most severe in RBDs in the Netherlands, Germany, Poland, Hungary and south-east England, and less severe in RBDs in Finland, the Baltic countries, as well as in many RBDs in Spain, Italy, Greece,  Bulgaria  and Cyprus. In coastal and transitional waters the hydromorphological pressure is considerably less than in freshwater bodies, and is mainly a problem along the Greater North Sea coast of Germany, the Netherlands and Belgium, as well as the in the northern coast of Spain and southern coast of Italy. Further details on hydromorphological pressures can be found in the Hydromorphology Thematic Assessment report.

Figure 5.5 Proportion of classified water bodies in different River Basin Districts affected by hydromorphological pressures for rivers and lakes (left panel) and for coastal and transitional waters (right panel) (percentage, based on number of classified water bodies). 

Notes: A water body is defined as affected by hydromorphological pressures if it is reported with any of the aggregated pressure types “ Water abstraction”, “Water flow regulations and morphological alterations of surface water“,“River management“,“Transitional and coastal water management“ and “Other morphological alterations“ and/or any of the corresponding disaggregated pressure types. Member states which have reported pressures, but where certain RBDs are marked as “no data reported” should indicate whether this particular pressure has not been reported in this RBD or whether no water bodies in this RBD are affected by this particular pressure.

5.6.     Relationships of ecological status or potential and pressures in rivers with population density and proportion of arable land

When population density and proportion of arable land increases, the ecological status or potential of river water bodies clearly deteriorates and the pressure increases, both for diffuse pollution, as well as for hydromorphological pressures (figure 5.6). The ecological status or potential changes from ca. 40% to ca. 80% of classified river water bodies in less than good status when population density and proportion of arable land increases from the lowest to the highest category. This pattern is a clear indication that population density and proportion of arable land are two major drivers responsible for the pressures affecting the ecological status or potential of European rivers. 

When population density and proportion of arable land is low (less than 15 inhabitants per km² and 10% arable land), the majority of classified river water bodies are reported to have good or better ecological status or potential and to be  without significant pressures. Diffuse pollution affects only a small proportion of the river water bodies (less than 15%). Hydromorphological pressures are nevertheless reported for a substantial proportion of the classified river water bodies (30-40%) even at the lowest level of population density and proportion of arable land, which is probably related to the use of many upstream rivers in mountain areas for hydropower production. 

At the highest levels of population density and proportion of arable land (more than 200 inhabitants per km² and 40% arable land), less than 25% of the classified river water bodies are in good or better ecological status or potential, and between one third and half of these water bodies are reported to be in poor or bad ecological status or potential.  At this highest level of the two major drivers, as much as 80-90% of the river water bodies are exposed to significant pressures, with diffuse pollution and hydromorphological alterations affecting 60-70% of the classified river water bodies.

Figure 5.6.  Ecological status or potential of classified river water bodies in different categories of population density (left upper panel) and in different categories of arable land in the river basin (right upper panel) , proportion of classified river water bodies with and without pressures in different categories of population density (left middle panel) and in different categories of arable land in the river basin (right middle panel), proportion of classified river water bodies with hydromorphological or diffuse pressures in different categories of population density (left lower panel) and in different categories of arable land in the river basin (right lower panel). 

Notes: The designation of river water bodies to population or arable land categories is made at RBD level, i.e. all water bodies in the same RBD are in the same category. The number of classified river water bodies in the different population density categories or arable land categories is indicated in brackets. In the pressure plots the member states not reporting the given pressures are excluded from the number of classified water bodies. Swedish surface water bodies where the pressure reporting is considered only to be related to airborne mercury contamination are defined as not affected (see text). See appendix for further details.

5.7.     Appendix with Notes for figures and tables.

Figure 5.0

Table 5.0 Proportion of classified water bodies in less than good ecological status or potential, with pressures and with impacts in different water categories.

Ecological status or potential:  Surface water bodies that are not classified include water bodies in Denmark, Portugal, Malta and Slovenia, who have not yet reported, water bodies in some RBDs which are not reported (see figure 5.2) and water bodies reported as unclassified (see chapter 3.1). The total numbers of classified water bodies are thus:  Rivers: 75763, Lakes: 13849, Transitional waters: 629, Coastal waters: 2225.

Pressures and impacts: The member states excluded from the number of total classified water bodies due to non-reporting are: Pressures: Luxembourg, Romania, Slovakia, Belgium and Cyprus (the latter two only for coastal waters). Impacts : Poland, the Netherlands, Luxembourg, Romania, Slovakia, Belgium and Cyprus (the latter two only for coastal waters). Ireland only reported pressures and impacts for one RBD, so Irish water bodies are removed both from the number of water bodies affected and from the number of total classified water bodies. The total numbers of classified water bodies are thus :

Pressures : Rivers: 66136, Lakes: 12918, Transitional waters: 557, Coastal waters: 2162.

Impacts: Rivers: 64895, Lakes: 12291, Transitional waters: 543, Coastal waters: 2142.

For Sweden, the aggregated diffuse pressure type and the impact contamination by priority substances are considered to represent airborne mercury pollution only. Water bodies only affected by these specific pressure or impact types are considered not to be affected by pressures or impacts, respectively. The numbers of such redefined water bodies are:

Pressures: Rivers: 7987, Lakes: 4677, Transitional waters: 0, Coastal waters: 248.

Impacts: Rivers: 11452, Lakes: 5050, Transitional waters: 0, Coastal waters: 126.

Figure 5.1:

In cases where length (rivers) and area (remaining water categories) data were considered suspicious, these water bodies were excluded from the analysis by length or area. These were cases when length or area was 0 or below or when data were not reported. This occurred in all water categories. In addition there were cases of unrealistically high numbers, indicating erroneous unit. For rivers, all water bodies with length > 1000 km were removed. These were all Italian. No lake or transitional water bodies were removed due to too large area, but all coastal water bodies >6000 km2 were removed. These were all from the Spanish RBD ES100. The total numbers of classified water bodies used in this analysis were thus somewhat lower than in the analysis by count (see notes figure 5.0), i.e.:

Rivers: 74413, Lakes: 13828, Transitional waters: 614, Coastal waters: 2181.

Figure 5.3:

For the “No pressures”» and “No impacts” bars, the same member states are removed from the total number of classified water bodies as in figure 5.0. In the other bars, more member states may be removed from the total classified, if they have not reported that specific pressure or impact (for most pressures and impacts the member states can be identified in the member state plots in chapter 4). In some cases the lack of reporting may actually mean that no water bodies in the member state are affected by the specific pressure or impact. If that is the case, these member states should clarify this, as excluding these member states from the number total classified water bodies leads to overestimation of the proportion of water bodies affected by the specific pressure or impact.

For the “No pressures” and “No impacts” bars, the same numbers of Swedish water bodies are redefined as in the pressures and impacts bars in figure 5.0, respectively. In the “Diffuse sources” bars, Swedish water bodies reported with the aggregated diffuse pressure type as the only diffuse pressure are defined as not affected, that is:

Rivers: 14149, Lakes: 6842, Transitional waters: 16, Coastal waters:  548.

In the “Contamination” bars, all Swedish water bodies with this impact are defined as not affected (because Sweden did not report the impact type “contaminated sediments”), that is :

Rivers: 15474, Lakes: 7196, Transitional waters: 21, Coastal waters:  598.

Figure 5.4: For Sweden, water bodies are redefined as not affected by pollution pressures if the aggregated diffuse pressure type is the only pollution type reported (see notes figure 5.0). The following numbers of water bodies are redefined (EU RBD codes):

Figure 5.6: Only river water bodies from RBDs where category data are available are included (Population: 128, Arable land: 92 RBDs). In the final version of the report the aim is to include all reported RBDs in this analysis. The Member States removed from the number of classified river water bodies are the same as in figure 5.0 (for rivers, all Member States reporting pressures overall report hydromorphological and diffuse pressures). In the with/without pressures plots, all Swedish river water bodies with the aggregated diffuse pressure type only are defined as without pressures.  In the diffuse  sources bars, all Swedish river water bodies with the aggregated diffuse pressure type as the only diffuse pressure are defined as without diffuse pressures. The numbers are given here: