Eutrophication Peter Kristensen European Environment Agency

Review of studies: –OECD Environmental Outlook 2001 ( 2020; qualitative assessments; discharge of nitrogen from agriculture ) –VMM (Sep.) 2000: Report on the environment and nature in Flanders: scenarios MIRA-S 2000 –RIVM, 2000: Nationale Milieuverkenning ( Flanders & NL, development of sectors – S&I qualitative – submodules ) –CARMEN groundwater and surface water (PS(I))

OECD Environmental Outlook 2001 The prospective IEA assessment in the OECD Environmental Outlook provides economy-based projections of environmental pressures and conditions to The report contains chapters for the main sectors (agriculture, households and industry) and environmental issues (freshwater). The main drivers are development in population and economy. A substantial part of the chapters are a qualitative assessment of development including assessment of technological development and different policies. The only quantitative projection in relation to eutrophication is discharge of nitrogen from agriculture driven by agriculture production times an emission factor (kg N/$1000). Mtonnes

Flanders & Dutch National Environmental Outlook Both the Flanders and Dutch Environmental Outlook reports take the offset in projections of the activities in the main sectors (households, industry, agriculture), which in turn drives projections of the main pressures such nutrient surplus for agricultural land and discharge from waste water treatment plants. Agriculture: Based on estimates of development of livestock and crops grown and national policies, the nutrient input to soil is calculated. The nutrient surplus is calculated. Industry: Based on information on the development in industrial sectors and technological changes, emissions from industry are calculated. WWTP: Based on forecasts of the type of wastewater treatment and population connected to treatment plants, the discharge of nutrients is calculated. Models and methods are used to evaluate the effect of the change in the pressures on the state and impacts in groundwater, inland surface waters and coastal areas. The linkage between pressure and state/impact are generally weakly described.

Dutch National Environmental Outlook

Examples N-balance N&P source apportoinment Nitrate in groundwater P&N load Rhine and Meuse

Carmen model The Carmen model was used to make projections in the EEA (1999) Environment in the Europe at the turn of the century and the CEC study on European Environmental Priorities (RIVM 2001). The model estimates nitrate concentrations in groundwater, and N and P concentrations at the downstream end of large European rivers and in coastal areas. The inputs to the model are population, livestock and fertiliser use and by the use of emissions coefficients (e.g. N & P/inhabitant) the loading into water is calculated. Assessments of the DP relations for agriculture and WWT are outside Carmen.

Conclusions eutrophication Generally the SOE oriented prospective analysis described in relation to eutrophication are based on rather simple descriptions of development in driving forces and pressures. The linkage between the pressures, state and impact is in many cases weak. In many cases only qualitative assessments of state and impact are possible (e.g. the pressure are reduced by X% therefore the state must improve).

Agricultural outlooks

Agricultural projections

Fertiliser outlook

Conclusions scooping study The work of the EEA, as exemplified in the State of Europe's Environment at the Turn of the Century report, can already be regarded as an example of good practice. This is particularly true for the presentation of a combination of quantitative/-qualitative information. Good national examples (e.g. England&Wales Environment 2000 and beyond) Most existing outlooks are relatively simple descriptions of activities with limited treatment of the activity specific environmental issues. In addition, there is often very limited assessment of the likely future developments in either practices (behaviour – lifestyle; management plans) or technology. As a result, for most of these analyses, had they been done in the past they would have missed the most fundamental changes that explain the majority of the developments in environmental pressures. A simple test in looking at such outlooks is to ask 'would this have explained the past/observed trend?'

Marked decrease in river phosphorus concentration Models: Main drivers Population & economic development Cause of decrease in phosphorus concentration are construction/upgrading of UWWT plants, recession in AC and phosphate-free detergents Similar of decoupling fertiliser use, nutrient balances, pesticide use, ammonia emissions from agricultural production during the 1990s

Conclusions continued... Existing assessments are not generally aimed at quantifying environmental impacts. Rather they stop short at a description of the activity (DP). Although such work can be improved, it does not need to be duplicated by the EEA or the Topic Centres. Rather these assessments should remain the remit of other organisations. However, there is a need to raise awareness of this material and the ways in which it can be used for the integrated analysis of water issues. Given the complexity of the issues qualitative approaches are valid. Sometimes, given uncertainty, it is better to have a holistic qualitative overview than a limited quantitative assessment. Quantitative assessments should not be strived for if the results are so uncertain as to render them useless for policy purposes. A priority is in the development of better information on practices, behaviour and developments in technology. Information on these aspects will improve the quality of existing outlooks significantly.