5. conclusions

5. Conclusion

The current report gives an overview of national surface water quality monitoring activities in the countries in the European Environment Agency (EEA) area. The results from these national and large regional monitoring programmes could make the basis for the evaluation of the state and trends in water quality at the EEA level. On the basis of the current report and additional analyses, a European surface water information system could be elaborated, including criteria for incorporating national monitoring sites into the EEA network, proposals for harmonization and sampling procedures and variables to be measured, and ideas for information processing from national level to the EEA level.

The report presents summary descriptions of the monitoring activities in each country based on the supplied national descriptions. Generally, the countries have several national monitoring programmes focused on assessment of the environmental state of surface waters. Some countries have a long tradition for national coordination of their monitoring programmes, however, in most of the countries the monitoring of surface waters has traditionally been performed by regional or local organisations. During the 1980s and 1990s the growing need for national information on the environmental state of surface waters made it necessary to work out national coordinated monitoring programmes. In most cases these national programmes are based on the information collected by regional organisations.

Nearly all countries in the EEA area have a national monitoring programme with the purpose of assessing the chemical water quality of rivers. The networks consist generally of more than 100 sampling sites located in all major river systems and rivers in each country. In most of the programmes basic variables (eg. water flow, temperature, pH, conductivity), organic pollution indicators (eg. BOD5, dissolved oxygen, ammonium), nutrients (nitrogen and phosphorus), specific ions (eg. chloride, sulphate, potassium, calcium) are measured. At a reduced number of sampling sites heavy metals and organic micropollutants are generally measured. The sampling and measuring frequency are generally monthly or even more frequent. Most of the countries also have monitoring programmes with the purpose of estimating the riverine loading into coastal areas, or the loading by transboundary rivers. In the Nordic countries programmes have been established with the purpose of monitoring water quality and loading from small catchments. These monitoring programmes generally consist of up to 20 relatively small stream catchments with detailed integrated studies of both river water quality and of the catchment (eg. land use and soil type), the main purpose being to follow reference areas, loading from agricultural land or impact of acid precipitation.

Most European countries have a long tradition for local assessment of the river quality based on studies of macroinvertebrates. In some countries these activities have developed into national surveys/classifications of the biological quality of the main rivers. These national surveys are generally based on the results collected by the local organisations and made possible through national harmonisation and standardisation. In some countries (eg. Austria, Germany, Ireland, Luxembourg, and the United Kingdom), the national classification has been performed since the 1970s and the countries are generally assessing the river quality at two to five years intervals. Some of southern European countries and the Nordic countries have no national programme for the assessment of biological river quality.

Only a minor part of the countries in the EEA area has national monitoring programmes for the assessment of water quality of lakes; some countries have, however, local monitoring of lakes. The Nordic countries with their many natural lakes generally have one or several lake monitoring programmes. Generally, a "survey-type" monitoring programme including a large number of lakes, which are sampled with intervals of several years (5-10 years), is supplemented with more intensive programmes with a sampling frequency of several times a year and typically covering a small number of lakes. The lake monitoring programmes generally include measurement of basic variables (eg. temperature, pH, conductivity, dissolved oxygen), nutrients (nitrogen and phosphorus), specific ions (eg. chloride, sulphate, potassium, calcium). In addition, assessment of biological variables, especially phytoplankton, is also included in many of the lake monitoring programmes.

Norway, Sweden and Finland each have nation-wide surveys in order to assess the extent of acidification. The surveys include national sampling of 200 to more than 1000 water bodies, primarily lakes, and are generally performed with intervals of five to ten years. The Nordic countries and the United Kingdom and Ireland have monitoring programmes involving detailed studies of few catchments with the purpose of understanding the process of acidification and to analyze trends.

Information about marine monitoring programmes has been received from ten out of the seventeen countries. Most countries have one general marine monitoring programme, which may be divided into sub-programmes eg. one programme concentrating on coastal waters and one programme focused at the open marine waters. Most of the marine monitoring programmes include measurement of chemical and physical variables in the water column (basic variables (eg. temperature and salinity), oxygen condition, and nutrients) and many of the programmes include studies of the biota (phytoplankton, zooplankton, zoobenthos etc.). The sampling networks consist generally of a number of intensive sampling sites, typically less than 20 sites, with frequent sampling (> 12/yr) of the water column supplemented with an extensive network including several sampling sites and low frequent sampling (1-4/yr).

Reliable high quality information on the environmental quality of surface waters is essential for water management and the implementation of optimal measures that will improve environmental quality. Greater knowledge of water quality at the regional and European levels is essential if the management of surface waters at the European level is to be improved. The considerable information on the state of surface waters collected and reported by various large regional and national authorities may be a valuable input to a European Surface Water Information System. Consistency and comparability of the information processed by the information system would require some harmonization and standardization of the regional and national monitoring programmes. A successful European Surface Water Information System would have to include the following elements:

• A representative monitoring network,
• A harmonized sampling and analyzing programme,
• National and regional reporting of the environmental state of surface waters.