4.     Ecological status, pressures and impacts in different countries

4.1.     Introduction

This chapter provides information at the member state level on ecological status, pressures and impacts with sub-chapters for each water category: Rivers, Lakes, Transitional and Coastal waters. The information is based on data that has been reported by Member States along with their first River Basin Management Plans (WFD Article 13 reports).

Each water category is presented in the same way, showing two sets of figures using all classified water bodies in each country:

1. Three separate bar plots with one bar per country showing
   1. Ecological status class distribution, countries are ranked from top to bottom with those with the highest proportion of good and high ecological status on top and those with the lowest proportion of good and high on the bottom
   2. Proportion of water bodies with any pressure reported (red colour) and with no pressures reported (blue colour). Countries with no pressures reported for any water body have no bar in the figure.
   3. Proportion of water bodies with any impact reported (red colour) and with no impact reported (blue colour). Countries with no impacts reported for any water body have no bar in the figure.
2. Four separate bar plots with one or two bars per country showing the pressures and impacts that are most often reported.
   1. Point source and diffuse source pressures
   2. Organic enrichment and nutrient enrichment impacts
   3. Contamination impacts, including priority substances and contaminated sediments
   4. Hydromorphological pressures, including water flow regulation, river/transitional/coastal management, other morphological alterations, and water abstraction, and altered habitats (impacts)

For each water category the ranking of the countries is the same in all these plots and follows that given by the ecological status plot (1a above). 

For each water category there are also some case studies included.

4.2.     Rivers

4.2.1.      Main assessment of status and main pressures and impacts

Europe has an extensive network of rivers and streams. In total more than 80 000 river water bodies with a length greater than 900 000 km has been reported by Member States. Four countries, Sweden, France, UK and Germany, reported more than half of the river water bodies, while three countries, France, Germany and the UK accounted for nearly half of the river length.

The average length of the more than 80 000 reported river WBs is 12 km. Four Member States have reported river WBs that are twice as long as the EU20 average, and Latvia, Bulgaria and Poland have river WBs longer than 30 km. Austria, Ireland and Sweden have relatively short river water bodies with average length less than 5 km, which is less than half the EU20 average.

For rivers, there are 44 000 water bodies (58% of the total number), or 606 000 km (65% of total river length) reported to be in less than good ecological status or potential. The main causes for the poor ecological status/potential are emissions from diffuse and point sources coming from agricultural pollution, from urban waste water and industrial emissions, causing nutrient and organic enrichment, as well as hydromorphological changes causing altered habitats.

Figure 4.1 Ecological status or potential, pressures and impacts of classified river water bodies in different member states sorted by proportion of good or better ecological status or potential.  The figure shows the percentage of total number of river classified water bodies in different status classes (left panel), with and without pressures reported (middle panel),  with and without impacts (right panel).

Notes: The number of classified river water bodies is given in brackets for each member state. Empty rows in the pressures and impacts plots mean that no data on pressures and/or impacts are reported from those member states. These member states are also excluded from the overall EU results. 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.

Source: Based on data available in WISE-WFD database primo February 2012,  -  country results on ecological status, pressures and impacts are available here http://wfd.atkins.dk/report/WFD_aggregation_reports/swb_status   &

http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_status  & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_status

Many of the Central-European Member States with high population density and intensive agriculture, generally have only a small proportion of their river water bodies in good or better ecological status or potential (lower part of figure 4.1). A high proportion of river WBs with good ecological status or potential is mainly reported in Northern Europe (Sweden, Finland, Ireland), in two of the Baltic countries (Estonia and Latvia) and in some southern and eastern European member states (Spain, Romania, Slovakia). The large differences reported between some neighbouring member states, e.g. Latvia and Lithuania, the Czech Republic and Slovakia, as well as between Hungary, Romania and Bulgaria may partly be caused by different assessment approaches (see section 3.1.2), and need further analyses of population density and % arable land to be fully understood. 

The proportion of river WBs with no significant pressure or no impacts generally followed the ranking of Member States based on at least good ecological status, i.e. Member States having a more than 50 % of the river WBs in good ecological status generally also had the a high proportion of river WBs without pressures and with no identified impacts. Conversely, the Member States with a large proportion of WBs in less than good ecological status generally have the majority of river WBs with significant pressures and impacts.

Figure 4.2 shows the major categories of pressures and impacts affecting ecological status in European rivers. The proportion of river WBs affected by diffuse pollution (Fig. 4.2.a), nutrient enrichment (Fig. 4.2.b), as well as hydromorphological pressures and altered habitats (Fig. 4.2.d) generally corresponds to the proportion in good ecological status as shown in Figure 4.1 above. 

The most important pollution pressure comes from diffuse sources, causing nutrient enrichment impacts in the majority of rivers in most of the member states having the worst ecological status (lower part of figure 4.1), with the notable exception of Poland who reported very low diffuse pressures. Most member states with better ecological status report a lower proportion than the EU average of 35% to be affected by diffuse pressures and nutrient enrichment, with the exception of Finland who reported more than 40% of their classified river water bodies to be affected by diffuse pollution causing nutrient enrichment. 

Some member states still have important point source pollution, e.g. Poland and Belgium (Flanders), which is due to inefficient urban waste water treatment. This pollution are causing quite massive organic enrichment impacts in their rivers, explaining the poor ecological status. Most member states, however, have much less point source pollution due to substantial urban waste water treatment over the past decade(s), thereby causing organic enrichment in only a minority of rivers.

Contamination by priority substances coming from both point and diffuse source pollution is affecting less than 25% of rivers in most member states, except in two member states (UK and Belgium) (Fig. 4.2.c). This impact is not well reflected in the ecological status, as the assessment systems are not developed to measure this impact. It will however be important for the chemical status. In Sweden, all the water bodies are subject to the impact contamination by priority substances. This is also reflected in the reporting of diffuse pressures, and is mainly due to mercury in biota. This has little impact on ecological status, although it affects chemical status. See more on this in section 5.3.2.

Hydromorphological pressures causing altered habitats is the other major pressure in European rivers, affecting the majority of water bodies in Member States with a large proportion of rivers in moderate or worse ecological status or potential (Fig. 4.2.d).  [A large share of these rivers are heavily modified or artificial rivers.] In the Member States with better ecological status or potential this pressure and impact affect less than 50% of the classified rivers, but is still an important problem in many rivers.

Figure 4.2. Proportion of classified rivers exposed to different main pressures and impacts in different member states ranked by proportion of good or better ecological status/potential (fig 4.1)

Notes: The number of classified river water bodies is given in brackets for each member state. Empty rows mean that no data on the specific pressure and/or impact are reported from those member states. These member states are also excluded from the overall EU results. 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.

Source: http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_status  & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_status

4.2.2.      Case study: Rhine and Danube river basins on status and impacts

The river Rhine connects the Alps to the North Sea. The river has a length of 1300 km, and its catchment area covers approximately 200000 km2 spread over nine states  (7 EU member states). The catchment area has 58 million inhabitants, with about half of the surface area used for agricultural purposes, about one third is forest and protected areas and almost 10% is urbanized. The catchment area also contains extensive industrial and chemical parks.

Important tributaries of the Rhine are Neckar, Main and Moselle. The Lower Rhine splits in several braches that enter the coastal waters of the North Sea and the Wadden Sea.

The Rhine river basin is divided into nine subunits, the Alpine Rhine/Lake Constance, the High Rhine, Upper Rhine and Middle Rhine, the tributaries Neckar, Main and Moselle/Saar, and then the Lower Rhine and Delta Rhine. The latter subunit also includes the transitional and coastal water bodies of the North Sea and the Wadden Sea.  Some of these subunits (Alpine Rhine: AT, DE; Moselle/Saar: DE, FR, LU; and Delta Rhine: DE, NL) cover more than one national state (Figure 2.4.1).

The analysis of the ecological status or potential in the freshwater part of the Rhine river transect (figure 4.3) shows that the ecological conditions decline following the main stream of the river downstream from the Alps to the river mouth in the Netherlands. In the three uppermost sub-units (Alpine Rhine/Lake Constance and High Rhine) altered habitats is the main, or the only, impact (figure 4.3).  There are numerous reservoirs and barrages for hydropower generation. These structures disrupt river continuity. The impact by altered habitats increases downstream, where it to a larger extent is related to flood protection, maintenance of the navigation channel, water level regulation measures and hydropower.

The hydromorphological modifications have impacted the ecological function of the Rhine, by restricting river dynamics, loss of alluvial areas, impoverishment of biological diversity and creating obstacles to fish migration. Restoring biological river continuity and increasing habitat diversity are major objectives of restoration measures. Measures aim to improve fish migration, from the North Sea up to the Basel area, with the salmon and other species.

The proportion of water bodies affected by nutrient enrichment and (to a lesser extent) organic enrichment also increases markedly downstream, following the main stream. Excessive concentrations of phosphorus and nitrogen have an impact on ecological status through eutrophication. While phosphorus concentrations have decreased to a certain extent, further reduction is still necessary to restore ecological conditions for some parts of the Rhine district. The coastal water bodies at the downstream end of the Rhine are sensitive to elevated nitrogen concentrations, and targets have been set to further reduce nitrogen pollution and achieve good status in the coastal waters (North Sea and Wadden Sea).

Some substances still cause contamination problems in the Rhine district. Nowadays, 96% of the people living in the catchment area and many industrial plants are connected to wastewater treatment plants. Point sources contribute less to classical pollution than in the past. Nutrient enrichment and contamination is thus largely caused by diffuse sources.

Together these impacts can explain the decline in ecological conditions from upstream to downstream areas. In the downstream subunits (Lower Rhine and Delta Rhine) only a small proportion of the water bodies are in good status, mainly as a consequence of the altered habitats and nutrient enrichment.

Figure 4.3 Relative distribution of ecological status or potential of classified fresh surface water bodies in sub-units of the Rhine RBD given as percentage of total number of water bodies in different ecological status classes (left panel). The percentage of total number of classified fresh surface water bodies affected by various impacts in sub-units of the Rhine RBD (right panel).

Notes: The Netherlands did not report impacts. The impact type “Contamination” means surface water bodies with the impact contamination by priority substances and/or contaminated sediment.

The map of ecological status or potential of Danube sub-units (figure 4.4, upper panel) does not to such a large extent as the Rhine map reflect an upstream-downstream decline in ecological conditions. Rather, it shows the difference between higher altitude, less densely populated areas (western Austria, northern Slovakia, mid-Romania) and lower altitude, more densely populated areas with more intensive agriculture (south Germany, eastern Austria eastern Czech Republic, Hungary, eastern Romania). The main stem of the Danube is largely flowing through the sub-units with the worst ecological conditions, while the conditions are better in the tributary sub-units.

The differences between the higher and lower lying areas are less evident from the impacts map of the Danube sub-units (figure 4.4. lower panel), due to the lack of reporting impacts from Slovakia and Romania. However, it does show nutrient enrichment in the lower lying areas of south Germany, eastern Austria, the Czech Republic and mid-Hungary. It also shows the strong impact of altered habitats many places.

Figure 4.4. Relative distribution of ecological status or potential of classified fresh surface water bodies in sub-units of the Danube RBDs given as percentage of total number of water bodies in different ecological status classes (upper panel). Percentage of total number of classified fresh surface water bodies affected by various impacts in sub-units of the Danube RBDs (lower panel).

Notes: Slovakia and Romania did not report impacts. The impact type “Contamination” means surface water bodies with the impact contamination by priority substances and/or contaminated sediment.

4.2.3.      Case studies, Ecological status of rivers in Germany and Sweden

Germany – Ecological status of different river types

Source: BMU/UBA 2010: Water Resource Management in Germany, Part 2 - Water Quality

Germany has identified 9070 river water bodies with a total length of around 127 000 kilometres. The length of all natural watercourses totals 74 506 km, corresponding to 59 % of the total river length. The proportion of heavily modified water bodies (HMWB) is 31 %, while artificial water bodies (AWB) account for 10 %. The natural river water bodies have been divided into 25 river types characterized by their location in the different eco-regions and the geological, morphological and hydrological characteristics of the river and the catchment.

An assessment of natural river water bodies reveals that by river length 14 % of the length is high or good ecological status, while 37 %, 33.5 % and 15.5 % are in moderate, poor or bad status, respectively. The most common reason for failing to achieve a “good ecological status” are changes in hydromorphology in natural river water bodies, and the high levels of nutrient pollution.

There are significant differences in the ecological status of the different German river types (Figure 5.x). More than 60 % of the natural river water bodies of the Alps and of the Pleistocene sediments in the Alpine foothills have at least “good” ecological status. Of the other watercourse types of the alpine foothills and Central German Highlands, 20 % are classed as having a “good” status, while 30 to 50 % are classed as “moderate”. Among North German lowland streams and rivers, the proportion of good status is generally well below 10 %. Generally speaking, more than 70 % of the river length in many lowland watercourse types has an ecological status worse than “moderate”. None of the large rivers have high or good ecological status.

Figure 4.5 Percentage distribution of ecological status classes in natural German river water bodies per common groups of river types.

Source: Federal Environment Agency (UBA), data supplied by LAWA, data source: Berichtsportal WasserBLIcK/BfG, as at 22 march 2010

The Po River, Italy

The longest river in Italy, the river Po, flows eastward across northern Italy from the Cottian Alps to the Adriatic Sea near Venice. The 652 km long river has a 74 000 km² drainage area of which 41 000 km² is mountainous and the remaining 29 000 km² is located in the Po valley encompassing the lowland plain of rich soil. There are 450 lakes in the drainage basin, and 141 tributaries add to the river that discharges an average 1540 m³/s into the Adriatic Sea through a wide delta. The amount of water discharged by Po is approx. 50% of the total freshwater input to the northern Adriatic Sea.

On the North side the flux of water is regulated by five large lakes. These lakes are directly connected to the main tributaries of the Po River. The retention of water, nutrient and particulate material in the lakes reduce the discharge of pollutants to the river. The landscape has changed due to increased urbanisation and intensified agriculture production over the past century. In recent years a large proportion of the natural vegetation (nearly 25%) in the riparian zone of the Po river has been replaced with plantations of poplars harvested for cellulose.

Due to an uneven precipitation pattern, the river is subject to periodic heavy flooding which is intensified by the fast runoff from the increasing urban areas. More than half the river length is controlled with a system of dikes to prevent flood damage.

Driving forces and Pressures

The Po River basin is a strategic region for the Italian economy, with significant agriculture, industry and tourism sectors. The lakes in the northern part are important for tourism, but are affected by eutrophication, especially lake Garda, where nutrient reduction measures are still not sufficient to meet the WFD requirement of good ecological status.

The river passes a number of larger Italian cities and Turin is the industrial center of the region. Milan is indirectly connected to the river by a channel system.

More than 40% of the Italian workforce is employed in this region and produces nearly 40% of the national GDP. 55% of Italian livestock is found here and 35% of the agricultural production takes place in this region.

The principal farming areas are localised in the Po valley, covering 45% of the basin’s total area. Most of the agricultural land in the Po valley is arable land, drained by artificial ditches, and 50% of agricultural land is irrigated during summer. The major crops that are grown are wheat, maize, fodder, barley, sugar beets and rice – with the latter being especially water demanding. 

The United Nations World Water Development Report 3 (World Water Assessment Programme, 2009) summarises the water challenges in the Po River basin, concluding that the high level of regional development has put heavy pressure on water resources and led to degradation of surface and groundwater quality.

Averaged year flow rate is presently lower than water use permits, both for surface waters and for groundwater. Irrigation is by far the largest consumer of water, four times the consumption of industrial water and public water supply combined.

State

Surface and groundwater quality is affected by discharges and losses of pollutants from industrial, agricultural and household. Excessive nutrients and organics in surface water causes eutrophication in rivers and in lakes. Although a network of wastewater treatment facilities has stopped further degradation of water quality, it has not been sufficient to reverse the process. Groundwater resources continue to contain high concentrations of nitrates due to fertilizer use in agriculture, while excessive exploitation has caused salt intrusion into coastal aquifers and, in some places, ground subsidence.

More than half of the nitrogen and phosphorus loads in the river Po originate from diffuse sources – and the role of the intensive agriculture activities on the plain is obvious. The results of scenario analyses by the turn of the century indicated that the measures imposed by the EU Nitrates Directive and the EU Wastewater Treatment Directive may not be stringent enough to achieve a large reduction in the N and P loads in the river Po (de Wit M.1 and Bendoricchio G., 2001).

The nutrient enriched water has a negative impact on the ecological status of the main river and its tributaries (Figure 4.6), showing that the whole river basin, except a few minor tributaries, fails the WFD objective of good ecological status. Moreover, when the water discharges into the Adriatic Sea the high nutrient load leads to eutrophication of the coastal waters. Paleo analyses of marine sediments covering the period 1830–1990 have revealed that a progressive increase in eutrophication took place in the beginning in the 20th century - particularly marked between 1930 and 1978. After 1978, the situation has improved, but still not recovered (Sangiorgi and Donders, 2004).

Response

Although policy tools for managing and safeguarding water resources have been implemented at national level for some time, there have been long lasting problems with the implementation and enforcement of rules and regulations at a regional level.

A set of integrated water management plans as well as flood risk management plans are adopted in all regions of the Po river basin. In 2009 all these plans were homogenised into the integrated river basin management plan at District level according to the WFD.

The Po Valley Project is a new integrated project that aims to integrate actions and measures for water quality, flood risk control, cultural and tourism requirements over a 6 year period from 2009 - 2015.

Figure 4.6 - Time serie (1985-2001) of nitrate concentration from the monitoring station at Pontelagoscuro (near the river mouth).

Copied from Salvetti et al. (2006).

Figure 4.7 - Mean phosphate concentration for the Po river basin taken from WISE SoE.

Figure 4.8 - Ecological status of the Po river and its tributaries from the source (left side) to the mouth (right side) (Bortone, 2009).

Sweden: Ecological status of surface waters in the North Baltic RBD                                    

Source: North Baltic River Basin Authority 2009: River Basin Management Plan for the North Baltic River Basin District, 2009-2015. (185 pp). Chapter 7: Status 2009.

The North Baltic River Basin District is the part of Sweden with highest pressures and impacts due to many large cities (e.g. Stockholm, Uppsala and Örebro) and large areas with intensive agriculture. According to the first river basin management plan as much as 75% of the 1111 natural surface water bodies (excluding 19 heavily modified or artifical water bodies) have been reported to be in moderate or worse ecological status, including the large lake Hjälmaren (Figure 4.9). Only one water body (a lake) is classified as having high ecological status, whereas 42 water bodies are in bad status.

Nutrient enrichment mainly from diffuse source pollution is the main pressure and impact in lakes, transitional and coastal waters, while hydromorphological pressures, in particular migration barriers for fish, is an important additional pressure and impact in the rivers.

Figure 4.9. Ecological status for surface water bodies in the North Baltic RBD, Sweden.

4.3.     Lakes

4.3.1.      Main assessment status and main pressures and impacts

In total around 18 000 lake water bodies with an area greater than 90 000 km² has been reported by 21 Member states. Two countries, Sweden, and Finland, reported more than two thirds of the lake water bodies and lake area.

The average area of the more than 18 000 reported lake water bodies is 5.1 km². Seven Member States (Austria, Estonia, France, Greece, Hungary, Lithuania, and Spain)  had average size of lake water bodies greater than 10 km². Half of the reported lakes are less than 1 km² in area and more than 87% of the reported lake water bodies have an area less than 5 km². Only 78 of the reported lake water bodies have an area greater than 150 km2; more than half of these are found in Finland and Sweden.

For lakes, there are close to 6000 water bodies (43% of the total number), or close to 31 000 km² (39% of total lakes surface area) reported to be in less than good ecological status or potential. The main causes for the poor ecological status or potential in these lake WBs are emissions from diffuse sources coming from agricultural pollution, causing nutrient enrichment, as well as hydromorphological changes causing altered habitats.

Figure 4.10 Ecological status or potential, pressures and impacts of classified lake water bodies in different member states sorted by proportion of good or better ecological status or potential.  The figure shows the percentage of total number of lake water bodies in different status classes (left panel), with and without pressures reported (middle panel),  with and without impacts (right panel).

Notes: The number of classified lake water bodies is given in brackets for each member state. Empty rows in the pressures and impacts plots mean that no data on pressures and/or impacts are reported from those member states. These member states are also excluded from the overall EU results. 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.Source: Based on data available in WISE-WFD database primo February 2012,  -  country results on ecological status, pressures and impacts are available here http://wfd.atkins.dk/report/WFD_aggregation_reports/swb_status  &

http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_status & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_status

Many of the Central-European Member States with high population density and intensive agriculture, generally have less than half of their lake water bodies in good or better ecological status or potential (lower part of figure 4.10). The highest proportion of lake WBs with good ecological status or potential is reported in Austria, where close to all lake water bodies are reported to be in good or better status. Also in Northern Europe (Sweden, Finland, Ireland), and in two of the Baltic countries (Estonia and Lithuania), as well as in Cyprus the majority of lake water bodies are reported to be in good or better ecological status or potential. The large differences reported between some neighbouring member states, e.g. Lithuania and Latvia, or Hungary and Romania may partly be caused by different assessment approaches (see section 3.1.2), and need further analyses of population density and % arable land to be fully understood.

In some member states there are large differences between the proportion of lake and river water bodies in good or better ecological status or potential, e.g. in Romania, where less than 20% of the lake water bodies (Fig. 4.10), but more than 60% of the river water bodies (Fig. 4.1) are reported to be in good or better ecological status or potential.  In Lithuania, the situation is opposite with better status in the lakes than in the rivers: close to 70% of the lakes water bodies, but only 40% of the river water bodies are reported to be in good ecological status or potential. Also in Austria a much better status has been reported for the lake water bodies than for river water bodies. These differences can partly be caused by incomplete and more or less stringent class boundaries for assessment systems in lakes versus those for rivers, but can also be real differences caused by the location of lakes (lowland or upland) relative to rivers, or different pressures and restoration efforts done over the past years in lakes versus rivers.   

The proportion of lake WBs with no significant pressure or no impacts generally followed the ranking of Member States based on at least good ecological status, i.e. Member States having a more than 50 % of the lake WBs in good ecological status generally also have a high proportion of lake WBs without pressures and with no identified impacts. Conversely, the Member States with a large proportion of WBs in less than good ecological status generally have the majority of lake WBs with significant pressures and impacts. The exception is Latvia who has not reported any significant pressures nor impacts for close to 100% of their lake water bodies, in spite of having more than half of their lake water bodies in less than good ecological status or potential. Also Poland reports lower pressures on their lake water bodies (less than 20% with pressures) than the ecological status reporting would suggest (less than 50% in good or better status). These inconsistencies may be caused by reporting mistakes, or lack of pressure information.

Figure 4.11 shows the major categories of pressures and impacts affecting ecological status in European lakes. The proportion of lake WBs affected by diffuse pollution (Fig. 4.11.a), nutrient enrichment (Fig. 4.11.b), as well as hydromorphological pressures and altered habitats (Fig. 4.11.d) generally corresponds to the proportion in good ecological status as shown in Figure 4.10 above. 

Figure 4.11. Proportion  of classified lakes exposed to different main pressures and impacts in different member states ranked by proportion of good or better ecological status/potential (fig 4.10)

Notes: The number of classified river water bodies is given in brackets for each member state. Empty rows mean that no data on the specific pressure and/or impact are reported from those member states. These member states are also excluded from the overall EU results. 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.

Source: http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_status & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_status

The most important pollution pressure comes from diffuse sources, causing nutrient enrichment impacts in the majority of lakes in most of the member states having the worst ecological status (lower part of figure 4.10). Exceptions are France and the Czech republic who reported quite low diffuse pressures relative to the large proportion of lakes reported to be in less than good ecological status or potential. For the Czech republic this can be explained by the high proportion of lakes or reservoirs affected by hydromorphological pressures and altered habitats (fig. 4.11.d), while this is not the case for France, who has reported also quite low proportion of lakes affected by hydromorpholo-gical pressures and altered habitats. 

Contamination by priority substances coming from both point and diffuse source pollution is affecting less than 20% of classified lakes in most member states (Fig. 4.11.c). This impact is not well reflected in the ecological status, as the assessment systems are not developed to measure this impact. It will however be important for the chemical status. In Sweden, all the water bodies are subject to diffuse pressures of priority substances and contamination impact, mainly due to mercury in biota, but this has little impact on ecological status, although it affects chemical status. Therefore these data has been excluded from the analyses of pressures and impacts affecting ecological status.

Point source pollution of lakes is generally reported to affect less than 25% of lake water bodies. This low proportion of lakes being affected by point source pollution is due to substantial urban waste water treatment over the past decade(s), thereby causing organic enrichment in only a minority of lakes in most countries. The exception here is Greece and in particular Belgium where most of the lake water bodies are affected by organic enrichment in spite of low proportions reported to receive point source pollution.

Hydromorphological pressures causing altered habitats is the other major pressure in European lakes, affecting the majority of water bodies in Member States with a large proportion of lakes in moderate or worse ecological status or potential (Fig. 4.11.d).  [A large share of these lakes is heavily modified or artificial reservoirs.] In Member States with better ecological status or potential this pressure and impact affect less than 50% of the classified lakes. Some of these pressures may also affect only a part of the lake shore, and thus may in some cases not be sufficient to degrade the ecological status of the whole lake water body.

4.3.2.      Ecological status, pressures and impacts of Europe’s largest lakes

General overview

The largest lakes of Europe are the lakes Ladoga and Onega in Russia, the lakes Vänern, Vättern and Mälaren in Sweden, Lake Saimaa in Finland, Lake Peipsi in Estonia/Russia, and Lake Ijsselmeer in the Netherlands. All these lakes have a surface area more than 1000 km².

Based on the member states reporting of lake water bodies in the river basin management plans, there are 67 lake water bodies with a surface area larger than 150 km². One third of these are in less than good ecological status or potential (Figure 4.12).

Most of the large lake water bodies are found in Sweden and Finland, and the large majority of these (74%) are in good or better ecological status or potential.  The only large lake water body reported to be in poor status in these Nordic member states is the Swedish lake Hjälmaren. Lake Hjälmaren is a shallow, lowland lake situated in a region with lime-rich clays and large agricultural areas surrounding the lake contributing to the nutrient loading of the water. The lake is used as a freshwater reservoir, as a recipient of sewage water-mainly from the town Örebro in the westernmost part - and for recreational purposes. The accelerated eutrophication during the last thirty years has especially affected the two basins closest to the town Örebro due to the increased population of the town (http://www.ilec.or.jp/database/eur/eur-14.html ).

Figure 4.12. Ecological status or potential of classified lake water bodies with surface area more than 150 km².

Notes: Total number of classified large lake water bodies > 150 km² is given in brackets.

Source: Based on data available in WISE-WFD database primo February 2012,  -  country results on ecological status is available here http://wfd.atkins.dk/report/WFD_aggregation_reports/swb_status

Parts of other large lakes, such as eutrophied shallow bays receiving diffuse or point source pollution may also be in less than good status, but these do not appear among the large lake water bodies shown in figure 4.12 because they are delineated as separate water bodies with surface area less than 150 km².  Only half of the large lake water bodies in the rest of Europe (excluding Sweden and Finland) are in good or better ecological status or potential.

Slightly more than half of the large lake water bodies (53%) are reported to have no significant pressures (fig. 4.13), while close to 80% are reported to have no impacts, indicating that some of the pressures have little impact on these large lake water bodies. Particularly the hydromorphology pressures seem to cause little impact, as 30% are exposed to hydromorphology pressures, but only 10% are reported to have altered habitats. Also for point source pollution and “other pressures” the proportion of exposed water bodies are higher than the impacted water bodies. The reason for the low impact of those pressures may be that they affect only small parts of these large lake water bodies, in contrast to the diffuse sources which cause nutrient enrichment in almost all the water bodies where this pressure is reported.

Figure 4.13. Percentage of total number of classified large lake water bodies with surface area over 150 km² and with or without identified significant pressures (left) and impacts (right).

Notes : The percentage is calculated against the total number of classified large lake 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. The impact type “Other impacts” means surface water bodies with at least one of the impacts “Saline intrusion”, “Elevated temperatures” or “Other significant 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.

Source: Based on data available in WISE-WFD database primo February 2012,  -  country results on pressures and impacts are available here http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_ & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_

Case studies large lakes. 

Lago Maggiore, Italy

Lago Maggiore in Northern Italy close to the Alpine region is a naturally oligotrophic lake with a surface area of 213 km2 and a mean depth of 177 m (max depth 370 m).

Photo not included

Source: http://en.wikipedia.org/wiki/File:Lago-Maggiore_1387.JPG.

The lake was exposed to increasing nutrient pollution from urban waste water in the 1960ies and 1970s, resulting in massive bluegreen algal blooms. However, due to urban waste water treatment, the lake has been gradually restored during the 1980 ies and 1990 ies and is now in good ecological status in terms of phytoplankton biomass (fig. 4.14). Also the taxonomic composition of phytoplankton has been restored from a typically eutrophic community structure dominated by  harmful filamentous bluegreen algae and large pennate diatoms to a more diverse phytoplankton community consisting of mostly smaller sized phytoplankton species.

Figure 4.14. Time series of phytoplankton biomass (as chlorophyll a) and total phosphorus (TP) from Lago Maggiore, Northern Italy.

Source: Giuseppe Morabito, CNR-Pallanza (Lyche Solheim et al. 2010).  Black line indicates good/moderate boundary for chlorophyll a for this lake type, according to Poikane 2009.

Lake Balaton, Hungary

Source: http://www.ilec.or.jp/database/eur/eur-04.html  and Hajnal and Padisak 2008

Lake Balaton in Hungary  is a calcareous, large, but very shallow lake with a surface area of 593 km2 and a mean depth of 3 m (max depth 12 m).  The distribution of macrophytes is restricted by strong waves and turbid waters to a relatively narrow belt. Only 3 percent of the lake surface is covered by reeds, and even less by submerged macrophytes. The major primary producers are phytoplankton. The annual commercial fish catch is 1200 tons.

The southern shore of the lake consists of sandy beach, while on the northern shore there are mountains of volcanic origin with old ruins on their tops and vineyards on their slopes. The picturesque landscape and the water ideal for swimming and other water sports attract 2 million tourists annually.

Photo not included 

Source: http://www.destination360.com/europe/hungary/lake-balaton

The sewage discharge from rapidly developing towns in the watershed, the growing use of fertilizers in agriculture and large animal farms increased the nutrient loading to the lake in the last decades. A rapid eutrophication became apparent by increased production and biomass of phytoplankton. Blooms of blue-green algae were frequent in the most polluted western part of the lake with biomass of 10-50 mg/l (Figure 4.15).

A restoration program was implemented in the 1990-ies with diversion of most of the municipal sewage, a reservoir was constructed to retain the nutrients carried by the Zala River and pollution due to liquid manure was reduced. The algal biomass has been largely reduced since the mid 1990-ies down to 5-10 mg/l (ref. Hajnal and Padisak 2008), but is still probably above the WFD target for very shallow calcareous lakes (L-CB2 lakes good/moderate boundary for chlorophyll a is 23 µg/l, Poikane 2009, corresponding to a biomass of roughly 2-4 mg/l).

Figure 4.15. Algal biomass (black bars) and taxonomic composition index (Q-line) in the western basin of Lake Balaton, Hungary (Keszthely station) from 1965-2005.

From Hajnal and Padisak, 2008.

Lake Vänern, Sweden

source: http://projektwebbar.lansstyrelsen.se/vanern/SiteCollectionDocuments/sv/Rapporter-publikationer/vvf-arsrapport_2011-webb.pdf ) &http://www2.dpes.gu.se/project/Vanern2012/welcome.htm

Photo not included 

Source: http://www.panoramio.com/photo/3576437

With a size of 5600 km² Vänern is the largest lake within the European Union, and among the 30 largest in the world. The lake is a shallow, lowland lake with a mean depth of 27 m (max depth 106 m). Its location and size gives the lake a maritime character with unique fauna and flora elements, which are recognized in several NATURA2000 areas. Around 300 000 inhabitants lives around the lake and have it as its freshwater source. The lake is the largest water power regulation dam in Sweden with a volume of 153km³, and it is commercially used both for transport and for fishing. The lake is also important for recreation both for tourists and for those living in the area.

Not all this usages of the lake are without conflicts and the environmental condition for ecosystems are changing due to climate change effects and changed water tapping routines and others pressures.

The current algal biomass in the off-shore waters is low (2-3 µg/l  chlorophyll a), reflecting the low phosphorus concentrations (6-8 µg/l), corresponding to good ecological status (Figure 4.16).

While the main basin satisfy the WFD requirement of good ecological status, there are 15 local bays with less than good ecological status, due to nutrient enrichment causing elevated algal biomass and affecting the local flora and fauna.

Figure 4.16. Phytoplankton mean biovolume from 1979-2010 of dominant taxonomic algal groups at three stations in Lake Vänern. The horizontal lines are long-term mean values for the whole period.

4.3.3.      Case studies:  Ecological status of lakes in The Netherlands and Denmark

Both the Netherlands and Denmark have a long tradition for monitoring and reporting water quality of their lakes. A brief summary of the results are included below.

The Netherlands

Source: PBL 2010: Nutriënten in het Nederlandse zoete oppervlaktewater: toestand en trends. & http://www.compendiumvoordeleefomgeving.nl/indicatoren/nl0503-Vermesting-van-meren-en-plassen.html?i=26-79 & Pot, R. 2010: Status and trends in water quality of Dutch lakes and ponds.

The eutrophication in Dutch lakes and ponds is greatly reduced since 1985, but the concentrations of nitrogen, phosphorus and chlorophyll- a, and transparency are still high (Figure 5.y). In recent years water quality has not improved very much.

Mainly due to eutrophication 444 out of 447 Dutch lake water bodies have less than good ecological status and potential.

Figure 4.17: Trend in summer average concentration of nitrogen, phosphorus and Chlorophyll and water transparency (Secchi depth) in Dutch lakes

Source: PBL 2010

Denmark

Source: Normander et al. 2009: Natur og Miljø 2009  and Nordeman et al. 2011: Vandmiljø og Natur 2010. NOVANA. Tilstand og udvikling – faglig sammenfatning.

Similar to the Dutch lakes there have since the 1990s been a significant improvement in the water quality of the Danish lakes, with marked reductions in nutrient concentrations and chlorophyll and improvement in water transparency. However, as with the Dutch lakes the majority of Danish lakes do not yet achieve good ecological state and additional reduction in nutrient loading are needed for most of the lakes to achieve good ecological status.

Figure 4.18. Trend in average concentration of nitrogen, phosphorus and Chlorophyll and water transparency (Secchi depth) in Danish lakes

Source: NERI/Aarhus University

4.4.     Transitional waters

4.4.1.      Main assessment status and main pressures and impacts

Figure 4.19.a shows that there are eight member states (Sweden, Lithuania, Latvia, Poland, Netherlands, Germany, Belgium (Flanders) and Romania) in which all transitional water bodies are in less than good status (moderate, poor or bad). A high percentage (> 80%) of transitional water bodies in less than good status is also reported for Greece and Bulgaria as well as for the French Mediterranean coast.

The worst ecological status or potential in European transitional waters is found in the Baltic Sea region (data from Sweden, Lithuania, Latvia and Poland), where all reported transitional water bodies are classified as less than good. Poland reported 50% of their transitional waters to be in bad status. Transitional water bodies draining to the Greater North Sea are predominantly in less than good status (moderate and less), with the exception of 30-40 % of the transitional water bodies in UK and France with good or better status.

The best situation is reported for transitional water bodies in the region of the Celtic Sea to the Iberian coast, where more than 74% of the French water bodies and 53% of the Spanish water bodies are in good or better ecological status or potential.  Another positive result in this region is that there are almost no water bodies reported to be in bad status, and also very few in poor status. For UK and Ireland however, a large proportion of transitional water bodies are reported to be in moderate status.

In the Mediterranean Sea, all member states with data for transitional water have reported a majority of water bodies to be in less than good ecological status or potential. The situation is worst in France with more than 90% of the classified transitional water bodies reported to be in less than good status and more than 60% in poor or bad status.  In Spain the situation is better with more than 40% of the classified transitional water bodies in good or better status or potential, although also in this member state the majority of the transitional waters along the Mediterranean coast are in moderate or worse status.  For the EU part of the Black Sea a large majority of the transitional water bodies in Bulgaria and Romania are reported to be in poor or bad status or potential, and only 13% are reported to be in good status (Bulgaria) (Figure 4.19. a). 

Figure 4.19. Ecological status or potential, pressures and impacts of classified transitional water bodies in different member states.  The figure shows the percentage of total number of transitional water bodies in different status classes (a), with and without pressures reported (b), with and without impacts (c).

Notes:  The number of classified river water bodies is given in brackets for each member state. Member States not reporting or not having  transitional waters have been included in the current diagram to ensure the comparability with the coastal diagrams included in the next section. Where ecological status or potential has been reported, empty rows in the pressures and impacts plots mean that no data on pressures and/or impacts are reported from those member states.  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.

Source: Based on data available in WISE-WFD database primo February 2012,  -  country results on ecological status, pressures and impacts are available here http://wfd.atkins.dk/report/WFD_aggregation_reports/swb_status  &

http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_status  & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_status

Most of the classified transitional waters are reported to be exposed to significant pressures causing significant impacts. The proportion of water bodies with/without pressures and impacts mostly corresponds to the reported ecological status, except for Poland, where one third of the water bodies (3 of 9 water bodies) is reported not to have any significant pressures, despite reporting poor or bad ecological status or potential for more than 85%. The proportion of water bodies exposed to pressures reported from Spain and France in the region of the Celtic Seas to the Iberian Coast is higher than those reported for the same member states for water bodies along the Mediterranean Sea, while the picture for the ecological status or potential is the opposite, with better status in the water bodies in the region of the Celtic Seas to the Iberian Coast than in water bodies along the Mediterranean. This paradox may be related to the more exposed nature of the transitional water bodies along the Atlantic coast of France and Spain than along their Mediterranean coasts, ensuring a better dilution of the pollution pressures causing less ecological effects.

In general, there is a qualitative relation between the proportion of transitional water bodies with/without pressures and those with/without impacts reported by the different member states.

Direct comparison of the selected pressures and impacts provides qualitative information on the correlation between diffuse pressures, predominantly from agricultural runoff, and nutrient enrichment. A similar relation is envisaged between point source pressures, presumably in the form of urban waste water treatment plants and the designated impact organic enrichment.

In the Baltic Sea, only Sweden and Poland provided information on significant pressures. At the same time, Sweden, Lithuania and Latvia reported information on impacts by nutrient and organic enrichment. Due to the lack of reporting of both pressures and impacts by Baltic countries, no conclusions can be drawn on the correlation between point/diffuse pressures and related impacts. Yet, this data points towards the problem of nutrient enrichment in the Baltic Sea region, reported in 81% of transitional waters, presumably due to diffuse sources. Organic enrichment is reported for 18% of transitional waters in the Baltic Sea, namely by Latvia and Lithuania.

In the Greater North Sea, point sources are reported in 53% of transitional water bodies as significant pressures, while 30% of waters are influenced by significant diffuse sources. All transitional waters in The Netherlands, Belgium Flanders and Germany are exposed to significant pressures from diffuse sources. All five German transitional water bodies belonging to the North Sea are influenced by diffuse sources, as well as impacted by nutrient enrichment. Both designated transitional water bodies in Sweden and > 80% of waters in The Netherlands and France are exposed to pressures by point sources. Point sources are also significant in 20-50% of the transitional water bodies in the other Greater North Sea countries. Other qualitative correlations between pressures and impacts are observed for UK and France.

16% of transitional water bodies in the Celtic Seas to the Iberian Coast are influenced by significant diffuse sources, reported in 5-40% of waters by Spain, France and UK. In the latter three countries, the proportion of water bodies impacted by nutrient enrichment is also on the same order (10-20 %). 35% of the transitional water bodies in the region are affected by significant point sources. These are reported in 30-50% of waters from Spain and UK and in an outstanding 90 % of transitional water bodies in France. The largest proportion of water bodies subject to organic enrichment is reported in the Celtic Seas to the Iberian Coast (31%), mainly by France (90 %) and to a lower extent by UK (35 %). The high proportion of point sources in French transitional water bodies correlate well with the equally high number of water bodies impacted by organic enrichment (Fig. 4.20. b).

In the Mediterranean Sea, significant diffuse sources are reported in 41% of the transitional water bodies. This pressure is important in 20-60% of waters from Italy, Greece, France and to a lesser extent Spain. Nutrient enrichment is also significant in 44% of transitional waters in the Mediterranean Sea, reported in 20-40% of the transitional water bodies of Spain, France, Greece and Italy. In the latter country, nutrient enrichment is significant in an outstanding 95 % of transitional water bodies, although the proportion of Italian transitional water bodies influenced by diffuse pressures is slightly above 60 %. As for point sources, 20-50% of the transitional water bodies in Spain, Italy and France are affected by significant pressures, equivalent to 24% of the reported transitional water bodies in the Mediterranean region. There is a general agreement between the proportion of diffuse pressures/impacts by nutrient enrichment and pressures by point sources/organic enrichment impacts reported by Mediterranean countries, except for Spain in which  around 20 % of the transitional water bodies are impacted by point sources whereas no organic enrichment impacts are reported.

Figure 4.20. Proportion of classified transitional waters exposed to different main pressures and impacts by sea regions and Member States bordering the sea regions.The results are shown in the same order as in figure 4.19.

Notes:  The number of classified transitional water bodies is given in brackets for each member state. Empty rows mean either that ecological status or potential has not been reported (see figure 4.19a) or that no data on pressures and/or impacts are reported from those member states.  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.

Source: http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_status & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_status

In the Black Sea area, both pressures are significant in ~90 % (diffuse sources) and 60 % (point sources) of the transitional water bodies. Impacts by nutrient enrichment are reported in 70 % of the water bodies but only  less than 10 % are impacted by organic enrichment. This assessment is primarily based on data from Bulgaria, since no information on pressures and impacts is available for Romania.

There is a direct link between hydromorphological pressures due to the construction of dams, locks, weirs for regulating water flow regimes and altered habitats resulting from the morphological alterations of surface water. Significantly altered habitats in transitional waters are a consequence of engineering works, which directly cause the removal of habitat or indirectly change the natural conditions. For example, dams and weirs cause obstruction for fish migration, lower the waters’ natural carrying capacity, aggravating impacts of pollution.

Significant hydromorphological pressures are reported in three regions; the Greater North Sea, the Celtic Seas to the Iberian Coast and the Mediterranean Sea. None of the countries in the Baltic Sea and Black Sea reported information on this particular pressure/impact. The largest share of altered habitats (62%) is reported in the Greater North Sea, ranging from 20% in France to 75-100% in UK and Germany. Despite the high share of altered areas, only 39% of transitional waters are reported to be subject to significant hydromorphological pressures, ranging from ~40% in UK and France to 100% in Netherlands and Germany. Of particular interest are the transitional water bodies in Germany, which are all under the influence of hydromorphological pressures as well as impacted by altered habitats. The reported hydromorphological pressures affecting 100 % of the transitional water bodies in The Netherlands cannot be supported by information on altered habitats due to the lack of reporting of impacts.

In the Celtic Seas to the Iberian Coast, France reported that ~10 % of transitional water bodies are equally affected by hydromorphological pressures and altered habitats. In Spain, > 40 % are influenced by hydromorphological pressures, whereas only 5 % are impacted by altered habitats. On the other hand, in the UK, more than 50 % of the transitional water bodies have been registered as altered habitats while < 40 % are affected by hydromorphological pressures.

44% of transitional water bodies in Mediterranean Sea are subject to significant hydromorphological pressures, ranging between 40-50% in Italy, Greece, Spain and France. Consequently, 40% of habitats in the region are classified as significantly altered.

4.4.2.      Case Study: Long-term trends of the ecological status in estuaries and coasts, using multiple ecosystem components, within the Basque Country (northern Spain)

Source: Case study provided by Angel Borja. AZTI-Tecnalia; Marine Research Division; Herrera Kaia, Portualdea s/n; 20110 Pasaia (Spain).

Although the WFD uses the principle ‘one-out, all-out’, when assessing the ecological status, Borja et al. (2004) proposed an integrated assessment method which takes into consideration the level of confidence of the methods using when assessing the status of each biological quality element (Borja and Rodríguez, 2010). This confidence takes into account the spatial and temporal variability of some of the biological elements, the absence of historical data for some of the elements, the absence of accurate methodologies for some of the biological elements, together with the lack of intercalibration for some of the others. Hence, a ‘decision-tree’ permits the derivation of a more accurate global classification, including also physico-chemical and chemical elements (see Borja et al., 2004, 2009). This method uses all elements in the assessment, weighting some of them, rather than removing elements and making the assessment with very few.

The Basque Country (northern Spain) has 12 small estuaries and 150 km of coastal waters, which have been monitored by AZTI, since 1995, for the Basque Water Agency. This network includes 51 coastal and estuarine stations sampled, from 1995 to 2010 (some of them since 2002). These stations are distributed amongst 18 water bodies (14 estuarine and 4 coastal).

The Basque Country is an industrialized area, which historically has supported high levels of pollution and diverse hydromorphological changes. Together with the abovementioned network, there is a good knowledge of the human pressures within the area, and their evolution (Borja et al., 2006).

When integrating all of the chemical, physic-chemical and biological (phytoplankton, macroalgae, macroinvertebrates and fishes) information, the whole evolution of the ecological status within the Basque estuaries and coasts can be seen (Figures 4.21a, 1b).

Figure 4.21. Ecological status of the Basque sampling stations (as a percentage), determined using an integrative method, which includes physico-chemical, chemical and biological quality elements (see Borja et al., 2004, 2009), in transitional (a) and coastal (b) water bodies.

Note: H: high status; G: good; M: moderate; P: poor; B: bad.

The estuaries show a progressive increase in their ecological status, reducing both bad and poor status and increasing moderate and good, especially after 2001 (Figure 1a). In recent times, around 30-50% of the transitional sampling locations are consistent with the WFD objective in achieving good status, by 2015. The coastal waters show the same trend in improvement of the quality (Figure 1b) and, in recent times, nearly all of the sampling locations achieve good or high status.

This result is consistent with the pressure evolution. Hence, water treatment in several of the river catchments and estuarine systems started in the 1980s. However, most of the engineering works within this region finished in 2000-2001, when the biological water treatment started, coinciding with a clear recovery in the status (Borja et al., 2009; Pascual et al., 2012). In general, the entire negative pressures (dredging, land reclamation, discharges of polluted waters, engineering works, etc.), or positive actions (water treatment, recovery of degraded wetlands, etc.), resulted finally in a response of biological and physico-chemical elements, as shown in Figure 4.21.

In this way, the integration of data presented here provides a good overview of the response of aquatic systems, to anthropogenic pressures or actions to remove them; this, in turn, shows the way in which these water bodies can reach the WFD objectives, by 2015. The positive trend in the status, and the time required to recover, should be taken into account when managing these aquatic ecosystems, as shown also in Borja et al., 2010).

4.5.     Coastal waters

4.5.1.      Main assessment status and main pressures and impacts

Figure 4.22a shows that all coastal water bodies in six out of 17 member states (Lithuania, Latvia, Poland, Netherlands, Germany (draining in Greater North Sea) and Romania) are in less than good status (moderate, poor or bad).

The worst situation is reported in the Baltic Sea countries, where overall 82% of coastal water bodies are not reaching environmental objectives. Around 2-30% of coastal water bodies in Germany, Finland, Sweden and Estonia are in good/high status. Also in the Greater North Sea, the ecological conditions of the coastal water bodies are not good for most of the member states, except in France and UK, who report good or better status for close to 60% and 70% of their coastal water bodies respectively. 

In the EU part of the Black Sea the situation for the coastal water bodies is also quite problematic with 60 % of the coastal water bodies in Bulgaria are in moderate and poor status, whereas all the coastal water bodies in Romania fail to achieve good status (Figure 4.22a).

The best ecological status of coastal waters is found in the Celtic sea to the Iberian coast, where waters from Spain, United Kingdom, France and Ireland are reported. In this area, 70-90% of coastal waters are reaching the environmental objective. There are almost no water bodies in poor or bad status in this region.  Similarly, 60-90% of coastal water bodies in the Mediterranean Sea are reported to be in good/high status.

Most coastal waters are subject to significant pressures and impacts, yet to lesser extent than transitional waters. The distribution of pressures and impacts mostly corresponds to reported ecological status, except for Poland, for which a low proportion of coastal water bodies are reported to be exposed to significant pressures, even though all water bodies are reported to be in less than good status.  On the contrary, Italy, in which most of coastal water bodies (85%) are in good or high status, reported a high percentage of waters being exposed to significant pressures and impacts (Figure 4.22. b, c). The same is true for the French Atlantic coast (Greater North Sea region and Celtic Sea to Iberian Coast region), where the large majority of coastal water bodies are reported to have good status, but only a minority is reported to be without significant pressures or impacts.

Figure 4.22. Ecological status or potential of classified coastal water bodies in different member states sorted by proportion of good or better ecological status/potential within each sea region. The figure shows the percentage of total number of classified coastal water bodies in different status classes (a), with and without pressures reported (b), with and without impacts (c).

Notes:   The number of classified river water bodies is given in brackets for each member state. Empty rows in the pressures and impacts plots mean that no data on pressures and/or impacts are reported from those member states. 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.

Source: Based on data available in WISE-WFD database primo February 2012- country results on ecological status is available here http://wfd.atkins.dk/report/WFD_aggregation_reports/swb_status

Diffuse sources are reported as significant in 42% of the coastal water bodies in Baltic Sea and ~20 % in the Greater North Sea. Sweden and Estonia reported that 10-40% of their coastal waters are under significant pressure from diffuse sources. Diffuse pressures appear to be more significant in Finland and Germany (Baltic Sea), in which 90-100% of coastal waters are influenced by diffuse sources. In the Greater North Sea, Germany (100 %), The Netherlands (70 %), France (45 %), UK (~20 %) and Sweden (< 5 %) reported diffuse pressures to variable extents. Only 3% of coastal waters in Baltic Sea and ~10 % in the Greater North Sea are impacted by nutrient enrichment (no data from Netherland and Belgium included). Although all of Germany’s coastal waters (Baltic Sea and Greater North Sea) are affected by diffuse pressures, the proportion of coastal water bodies affected by nutrient enrichment is only 20 % in the Greater North Sea, whereas no nutrient enrichment impacts were reported in the Baltic German coastal water bodies. In both regions, 19% of coastal water bodies are affected by pressures from point sources, which are generally less important than diffuse pressures. In the Baltic Sea, 8% of coastal water bodies are subject to organic enrichment. Reporting results are similar to those for the Greater North Sea (Figure 4.23.b). Due to the partial reporting on pressures and impacts by countries (Figure 4.23.b), it is not possible to establish a link between sources and nutrient/organic enrichment. For example, Lithuania reported that the two designated coastal water bodies are both impacted by nutrient and organic enrichment, yet no corresponding information on pressures is available.

Figure 4.23. Proportion of classified coastal waters exposed to different main pressures and impacts by sea regions and Member States bordering the sea regions. The results are shown in the same order as in figure 4.22.

Notes:  The number of classified coastal water bodies is given in brackets for each member state. Empty rows mean that no data on pressures and/or impacts are reported from those member states.  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.

Source: http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_pressure_status & http://wfd.atkins.dk/report/WFD_aggregation_reports/SWB_impact_status

Point sources are reported as significant in 18% of coastal waters in the Celtic Seas to the Iberian Coast (mostly in France; 70%) and in the Mediterranean Sea (mostly in Italy, France and Malta; 50-60%). In France (Celtic Seas to the Iberian Coast), the proportion of coastal bodies impacted by organic enrichment is also relatively high (~80 %), consistent with ~ 70 % affected by point sources. In the Mediterranean Sea, 15% of waters are a subject to organic enrichment mainly reported by Italy (40 %). Despite the relatively high proportion of coastal water bodies affected by point sources (50-60 %) in France (Mediterranean) and Malta, no organic enrichment impacts are reported by these countries. The contribution of significant diffuse sources in these two regional seas is even lower. Diffuse pressures (as well as nutrient enrichment impacts) do not seem to be important in the Celtic Seas to the Iberian Coast. In the Mediterranean Sea, most of the significant diffuse sources of pollution are reported by Malta (~70 %), followed by Italy (~30 %). Only 5% of the coastal water bodies are subject to nutrient enrichment, mainly reported by Italy (90 %) and France (30 %), despite the relatively low proportion of diffuse pressures reported by France (5 %). No impact information on nutrient enrichment is available for Malta.

As for the Black Sea, only data from Bulgaria is available on pressures and impacts. Bulgaria reported that 60 % of its coastal water bodies are impacted by point sources, whereas diffuse pressures affect half of the water bodies. However, merely 10 % are impacted by organic enrichment as opposed to greater than 80 % by nutrient enrichment. Impacts and pressures were not reported consistently in all regions, making it difficult to qualitatively related data on status, pressures and impacts on regional level (Figure 4.23.a, b, c).

Most countries reported significant hydromorphological pressures in 10-40% of the coastal water bodies, with the exception of the Netherlands, where 80 % of the coastal water bodies are under hydrodymorphological pressures. Due to the lack of reporting of impacts by The Netherlands, it is not possible to relate the hydromorphological pressures to altered habitats. Overall 7% of coastal waters are reported to have significant pressures due to hydromorphological alterations. (Figure 4.23.d)

4.5.2.      Case study: Baltic Sea

HELCOM identified several important pressures, caused by human activities. Coastal areas are mainly affected by point-source pollution and open-sea areas by fishing, riverine pollution and atmospheric nitrogen deposition. Another important issue is also disturbance of the seabed by construction, dredging and disposal of dredged material, which creates large impacts on local environments, whereas bottom trawling affects large areas of the sea. The cumulative impact of human activities is large in all areas except open-sea areas of the Gulf of Bothnia. (HELCOM, 2010)

This HELCOM Initial Holistic Assessment shows that the environmental status of the Baltic Sea is generally impaired (HELCOM, 2010). None of the open basins of the Baltic Sea has an acceptable environmental status at present. The integrated assessment of the ‘ecosystem health’ has revealed that only very few coastal areas along the Gulf of Bothnia can be considered healthy. In most of the coastal waters, nutrient concentrations and chlorophyll-a concentrations generally are elevated compared to both target values and reference conditions. (HELCOM, 2011).

Pollution

Nutrient concentrations in the Baltic Sea increased until the 1980s. In all areas except for the Gulf of Finland, phosphorus concentrations have declined during the past two decades but good environmental quality has not yet been re-established. Nitrogen concentrations have declined in the Gulf of Riga, Baltic Proper and Danish Straits. These declines are partly caused by lower nutrient loads from land-based sources, but changing volumes of hypoxia in the Baltic Proper significantly alter nutrient concentrations in bottom waters and, through subsequent mixing, also surface waters (HELCOM 2010). Countries have reduced the inputs of phosphorus and nitrogen to the Baltic Sea from 1990–2006d by 45% for phosphorus and 30% for nitrogen. Decrease of atmospheric nitrogen deposition was smaller, mainly because the increasing shipping activities in the Baltic, which is an important contributor to the atmospheric nitrogen deposition. (HELCOM, 2011).

 Environmental problems in the Baltic Sea have been aggravated by the presence of heavy metals such as mercury and cadmium, which have been shown to have harmful effects on aquatic life when accumulated over a period of time as well as physical loss and physical damage of the seabed. (HELCOM 2010)

Physical loss of the seabed

One of the largest concerns in the Baltic, the decline of biodiversity and abundance of species, is directly linked also to the physical damage and loss of the seabed and the associated destruction of the natural habitats. Natural seabed habitats are locally destroyed when constructions seal the sea floor or are altered, e.g., when sediments are dumped onto the sea floor smothering the benthic communities (Powilleit et al. 2006). This occurs at disposal sites of dredged material, when beaches are replenished with new sand, or the seabed is damaged during construction work for wind farms, cables, bridges, or pipelines. Scientific investigations have shown that the species composition at a smothered site is altered by favouring opportunistic species for several years (Harvey et al. 1998, Boyd et al. 2000, Martin et al. 2005).

Disposal sites occur near large harbor projects but also further out at sea. Most Baltic countries dispose of their dredged material at selected sites where special features hinder the dumped material from spreading to larger areas. (Figure 3a) However, the local hydrographic conditions also affect the recovery time of the site. Harbors, offshore wind farms, cables, bridges, coastal dams, coastal defence structures and oil platforms are distributed along the coasts of the Baltic Sea, especially on the south-western shores (Figure 3b). They cover the sea floor and have replaced the local habitats. In the future, additional sea floor areas in the Baltic are likely to be disturbed. Increasingly, sea areas are being reserved for more wind farms, underwater pipelines, data and electricity cables as well as the enlargement of municipalities, harbors, platforms, coastal erosion defence structures, piers and bridges at sea. Whilst the sealing structures destroy natural habitats, they also create new artificial habitats. (HELCOM, 2010)

Physical damage to the seabed

Physical damage to the seabed constitutes also one of the major pressures on the Baltic marine environment (Jones 1992, Jennings et al. 2001). It is caused by the exploitation of mineral resources, dredging, disposal of dredged material, bottom trawling, constructions on the seabed, and coastal shipping. The seabed is damaged by different types of activities causing pressures, including abrasion, siltation and selective extraction of mineral resources like sand and gravel. All three types of pressures change the sediment structure and damage the bottom-dwelling communities. When the seabed is left to recover, it should eventually re-stabilize and at a later stage be able to support a functional community again. (HELCOM, 2010)

4.6.     References

BMU/UBA 2010: Water Resource Management in Germany, Part 2 - Water Quality. Available at http://www.umweltbundesamt.de/uba-info-medien/3771.html

Borja, Á., J. G. Rodríguez, 2010. Problems associated with the 'one-out, all-out' principle, when using multiple ecosystem components in assessing the ecological status of marine waters. Marine Pollution Bulletin, 60: 1143-1146.

Borja, A., J. Franco, V. Valencia, J. Bald, I. Muxika, M. J. Belzunce, O. Solaun, 2004. Implementation of the European Water Framework Directive from the Basque Country (northern Spain): a methodological approach. Marine Pollution Bulletin, 48: 209-218.

Borja, A., I. Galparsoro, O. Solaun, I. Muxika, E.M. Tello, A. Uriarte, V. Valencia, 2006. The European Water Framework Directive and the DPSIR, a methodological approach to assess the risk of failing to achieve good ecological status. Estuarine, Coastal and Shelf Science, 66: 84-96.

Borja, A., J. Bald, J. Franco, J. Larreta, I. Muxika, M. Revilla, J. G. Rodríguez, O. Solaun, A. Uriarte, V. Valencia, 2009. Using multiple ecosystem components, in assessing ecological status in Spanish (Basque Country) Atlantic marine waters. Marine Pollution Bulletin, 59: 54-64.

Borja, Á., D. Dauer, M. Elliott, C. Simenstad, 2010. Medium- and Long-term Recovery of Estuarine and Coastal Ecosystems: Patterns, Rates and Restoration Effectiveness. Estuaries and Coasts, 33: 1249-1260.

Bortone, Giuseppe (General Director Environment, Coast and Soil Department Emilia-Romagna Region (March 18th, 2009). "Po Basin (Italy)" (pdf). Istanbul: Autorità di Bacino del Fiume Po. http://www.riob.org/wwf-5/po/07_BortoneItaliansideeventfinal.pdf. Retrieved on 6 June 2009.  Stato ecologico del fiume po e dei su oi affluenti nell’anno 2003.

de Wit M.1and  Bendoricchio G., 2001. Nutrient fluxes in the Po basin. The Science of the Total Environment, Volume 273, Number 1, 12 June 2001, pp. 147-161(15).

HELCOM, 2011. The Fifth Baltic Sea Pollution Load Compilation (PLC-5) Balt. Sea Environ. Proc. No. 128

HELCOM, 2010 Ecosystem Health of the Baltic Sea 2003–2007: HELCOM Initial Holistic Assessment. Balt. Sea Environ. Proc. No. 122.

Pascual, M., A. Borja, J. Franco, D. Burdon, J. P. Atkins, M. Elliott, 2012. What are the costs and benefits of biodiversity recovery in a highly polluted estuary? Water Research, 46: 205-217.

Nordeman et al. 2011: Vandmiljø og Natur 2010. NOVANA. Tilstand og udvikling – faglig sammenfatning

Normander et al. 2009: Natur og Miljø 2009  Available at http://www2.dmu.dk/Pub/FR751_B.pdf

PBL 2010: Nutriënten in het Nederlandse zoete oppervlaktewater: toestand en trends.

Pot, R. 2010: Status and trends in water quality of Dutch lakes and ponds. Research for Public Works Water Department; Roelf Pot, Oosterhesselen

Salvetti, R., Azzellino, A and Vismara, D., 2006. Diffuse source apportionment of the Po river eutrophying load to the Adriatic sea: Assessment of Lombardy contribution to Po river nutrient load apportionment by means of an integrated modelling approach. Chemosphere, Volume 65, Issue 11, December 2006, Pages 2168-2177.

Sangiorgi , F and Donders, T., 2004. Reconstructing 150 years of eutrophication in the north-western Adriatic Sea (Italy) using dinoflagellate cysts, pollen and spores. Estuarine, Coastal and Shelf Science. Vol. 60, Issue 1, May 2004, Pages 69-79.

Thulin,J. and Andrushaitis, A. The Baltic Sea, its past, present and future. Presentation. Link: http://www.ices.dk.

World Water Assessment Programme. 2009. The United Nations World Water Development Report 3: Water in a Changing World. Paris: UNESCO, and London: Earthscan. http://www.unesco.org/water/wwap/wwdr/wwdr3/pdf/WWDR3_Water_in_a_Changing_World.pdf

Aertebjerg, G., Andersen, J.H. & Hansen, O.S. (eds.) (2003) Nutrients and Eutrophication in Danish Marine Waters. A Challenge for Science and Management. National Environmental Research Institute. 126 pp. http://www2.dmu.dk/1_viden/2_Publikationer/3_ Ovrige/rapporter/Nedmw2003_0-23.pdf

4.7.     Appendix with Notes for figures and tables

Figure 4.1 /4.2/4.10/4.11/4.13/4.19/4.20/4.22/4.23

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 in all pressure and impacts plots. 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:

Figure 4.1: Pressures: 7987, Impacts: 11452

Figure 4.2a: Diffuse sources: 14149

Figure 4.2c: Contamination: 15474

Figure 4.10: Pressures: 4677, Impacts: 5050

Figure 4.11a: Diffuse sources: 6842

Figure 4.11b: Contamination: 7196

Figure 4.13: No pressures: 1, Diffuse sources: 13, No impacts: 13, Contamination: 16

Figure 4.19: Pressures: Greater North Sea: 0, Baltic Sea: 0, Impacts: Greater North Sea: 0, Baltic Sea: 0

Figure 4.20a: Diffuse sources: Greater North Sea: 1, Baltic Sea: 15

Figure 4.20c: Contamination: Greater North Sea: 2, Baltic Sea: 19

Figure 4.22: Pressures: Greater North Sea: 2, Baltic Sea: 246, Impacts: Greater North Sea: 5, Baltic Sea: 121

Figure 4.23a: Diffuse sources: Greater North Sea: 111, Baltic Sea: 437

Figure 4.23c: Contamination: Greater North Sea: 113, Baltic Sea: 485

Figure 4.2/4.11/4.20/4.23

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. “Hydromorphology” denotes the combination 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“. The impact type “Contamination” means surface water bodies with the impact contamination by priority substances and/or contaminated sediment.