In 2010, the highest concentrations of oxidized nitrogen were found in the Baltic Sea, in the Gulf of Riga and Kiel Bay, and in Belgian, Dutch and German coastal waters in the Greater North Sea. Reported stations in the Northern Spanish and Croatian coastal waters also showed high concentration levels. The highest orthophosphate concentrations were found in the Baltic Sea, in the Gulf of Riga and Kiel Bay, and in Irish, Belgian, Dutch and German coastal waters in the Greater North Sea. Coastal stations along Northern Spain and Southern France also showed high concentration levels.
Between 1985 and 2010, overall nutrient concentrations have been either stable or decreasing in stations reported to the EEA in the Greater North Sea, Celtic Seas and in the Baltic Sea. However, this decrease has been more pronounced for nitrogen. Assessments for the overall Mediterranean and Black Sea regions were not possible, data only being available for stations in France and Croatia.
For oxidized nitrogen concentrations, 14% of all the reported stations showed decreasing trends, whereas only 2% showed increasing trends. Decreases were most evident in the Baltic Sea (coastal waters of Germany, Denmark, Sweden and Finland, and open waters) and in southern part of the coast of the Greater North Sea. Increasing trends were mainly found in Croatian coastal stations.
For orthophosphate concentrations, 10% of all the reported stations showed a decrease. This was most evident in coastal and open water stations in the Greater North Sea, and in coastal stations in the Baltic Sea. Increasing orthophosphate trends, observed in 6% of the reported stations, were mainly detected in Irish, Danish and Finnish coastal waters (Gulf of Finland and Gulf of Bothnia) and in open waters of the Baltic Proper.
In 2010, the highest summer chlorophyll-a concentrations were observed in coastal areas and estuaries where nutrient concentrations are also generally high (see CSI 021 Nutrients in transitional, coastal and marine waters). These include the Gulf of Riga, Gulf of Gdansk, Gulf of Finland and along the German coast in the Baltic Sea, coastal areas in Belgium and The Netherlands in the Greater North Sea and in few locations along the coast of Ireland and France in the Celtic Seas and Bay of Biscay, respectively. High chlorophyll concentrations were also observed along the Gulf of Lions and in Montenegro coastal waters in the Mediterranean Sea, and along Romanian coastal waters in the Black Sea. Low summer chlorophyll concentrations were mainly observed in the Kattegat and open sea stations in the Greater North Sea, and in open sea stations in southern Baltic Sea.
Between 1985 to 2010, decreasing chlorophyll concentrations (showed in 8% of all the stations in the European seas reported to the EEA) were predominantly found along the southern coast of the Greater North Sea, along the Finnish coast in the Bothnian Bay in the Baltic Sea and in a few stations in the Western Mediterranean Sea and Adriatic Sea. In the Black Sea, it was not possible to make an overall assessment due to the lack of time series data. Increasing concentrations (observed in 5% of the reported stations) were generally observed in coastal locations in the Northern Baltic Sea but also in the open sea stations outside the north of the Celtic Seas. Most stations (87%) however showed no changes over time.
The concentrations were generally Low or Moderate for HCB and lindane, Moderate for cadmium, mercury and lead, and Moderate or High for PCB and DDT. A general downward trend was found in the Northeast Atlantic for lead, lindane, PCB and DDT and also in the Baltic Sea and Mediterranean Sea for lindane. A general upward trend was found in the Mediterranean Sea for mercury and lead.
Wastewater treatment in all parts of Europe has improved during the last 15-20 years. The percentage of the population connected to wastewater treatment in the Southern, South-Eastern and Eastern Europe has increased over the last ten years. Latest values of population connected to wastewater treatment in the Southern countries are comparable to the values of Central and Northern countries, whereas the values of Eastern and South-Eastern Europe are still relatively low compared to Central and Northern Europe.
The quality of water at designated bathing waters in Europe (coastal and inland) has improved significantly since 1990.
Compliance with mandatory values in EU coastal bathing waters increased from just below 80 % in 1990 to 93.1 % in 2011. Compliance with guide values likewise rose from over 68 % to 80.1 % in 2011.
Compliance with mandatory values in EU inland bathing waters increased from over 52 % in 1990 to 89.9 % in 2011. Similarly, the rate of compliance with guide values moved from over 36 % in 1990 to 70.4 % in 2011.
Concentrations of BOD and total ammonium have decreased in European rivers in the period 1992 to 2010 (Fig. 1), mainly due to general improvement in wastewater treatment.
See also WISE interactive maps: Mean annual BOD in rivers and Mean annual Total Ammonium in rivers
Average nitrate concentrations in European groundwaters increased from 1992 to 1998, but have declined again since 2004.
The average nitrate concentration in European rivers decreased by approximately 11% between 1992 and 2010 (from 2.5 to 2.2 mg/l N), reflecting the effect of measures to reduce agricultural inputs of nitrate as well as improvement in wastewater treatment.
Average orthophosphate concentrations in European rivers have decreased markedly over the last two decades, being more than halved between 1992 and 2010 (54% decrease). Also average lake phosphorus concentration decreased over the period 1992-2010 (by 31%), the major part of the decrease occurring in the beginning of the period, but is still ongoing. The decrease in phosphorus concentrations reflects both improvement in wastewater treatment and reduction in phosphorus in detergents.
Overall, reductions in the levels of freshwater nutrients over the last two decades primarily reflect improvements in wastewater treatment. Emissions from agriculture continue to be a significant source.
Over the last 10-17 years the Water Exploitation Index (WEI) decreased in 24 EEA countries (Fig.1), as a result of water saving and water efficiency measures. Total water abstraction decreased about 12 %, but one fifth of Europe's population still lives in water-stressed countries (approx. 113 million inhabitants).
At EU-15 level the gross nitrogen balance in 2000 was calculated to be 55 kg/ha, which is 16% lower than the balance estimate in 1990, which was 66 kg/ha. In 2000 the gross nitrogen balance ranged from 37 kg/ha (Italy) to 226 kg/ha (the Netherlands). All national gross nitrogen balances show a decline in estimates of the gross nitrogen balance (kg/ha) between 1990 and 2000, apart from Ireland (22% increase) and Spain (47% increase). The following Member States showed organic fertiliser application rates greater than the threshold of 170 kg/ha specified by the Nitrates Directive in 2000: the Netherlands (206 kg/ha) and Belgium (204 kg/ha). The general decline in nitrogen balance surpluses is due to a small decrease in nitrogen input rates (-1.0%) and a significant increase in nitrogen output rates (10%).