1. CIS workshop : assessment of the ecological status.
CIS workshop – 11&12 June Paris national classification systems for the assessment of ecological status of surface waters
CIS workshop : assessment of the ecological status.
3 sessions :
ecological significance and combination of the biological quality elements
role and place of the physico-chemical elements
effect of aggregation, uncertainty, confidence & precision
10 presentations : DGENV, Austria, Estonia, Czech Republic, Germany, the Netherlands, Sweden, UK, France
50 participants from 18 countries + EC
11-12 June, Paris

2. CIS workshop : assessment of the ecological status.
Main points (1)
State of play : different approaches and methods within national classification systems
selection of quality elements
combination of the biological elements
place of physico-chemistry
aggregation of data (temporally, spatially…)
CIS workshop : assessment of the ecological status.
11-12 June, Paris

3. CIS workshop : assessment of the ecological status.
Main points (2)
Illustrations taken from the various presentations :
Selection of quality elements :
all relevant biological elements listed in annex V
a selection of elements (based on former risk analysis, expert judgment, available methods & data…)
id. for physico-chemistry
Combination of the biological quality elements :
one out - all out principle
other combinations (based on expert judgement, reliability of indexes and data…)
Place and role of chemistry :
physico-chemical boundary values set in accordance with the biological classification
but some uncertainties remain : if chemistry does not match with biology, can we conclude that biology « overrides » chemistry ?
CIS workshop : assessment of the ecological status.
11-12 June, Paris

4. CIS workshop : assessment of the ecological status.
Main conclusion
General principles set in the guidance ‘Overall approach to the classification of ecological status and potential’ are valid
Differencies in implementing in practice the guidance
Part of those differencies are coming from different levels of maturity
Selection of QE can influence the results of the classification
Need of appropriate explaination and communication of the results
Despite the huge on-going work in the frame of IC, no final guarantee of « comparable levels of ambition » between MS
CIS workshop : assessment of the ecological status.
11-12 June, Paris

5. CIS workshop : assessment of the ecological status.
Proposed follow-up
Need for common views about the classification of ecological status : complement to the guidance, elaborated in 2003, based on practical case-studies
3 directions proposed :
How to ensure comparability between MS whereas different QE can be used for the classification ?
How to manage risks of misclassification (combination of biological elements, checking procedure for chemistry) ?
How to better communicate about the results of the final assessment ?
Agreement of the Water Directors (Dresden, June 18-19) to carry out this work within activity 4 of ECOSTAT.
CIS workshop : assessment of the ecological status.
11-12 June, Paris