Research and analysis

Uncertainty estimation for monitoring results by the Water Framework Directive (WRD) biological classification tools

In this study the variability of metrics is estimated for a specific classification tool in order to quantify precision and confidence as required by the Water Framework Directive.


Uncertainty estimation for monitoring results by the WFD biological classification tools

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The new European Union (EU) water policy, the Water Framework Directive (WFD), states that all European surface waters achieve good ecological status by 2015. The ecological status is an expression of the quality of the structure and functioning of biological elements associated with surface waters, classified in Annex V. Ecological status should be assessed via a reference condition approach using bio-assessment tools (further called ‘classification tools’) based on five biological elements (EU 2000) which in the case of rivers are: (1) phytoplankton, (2) macrophytes and phytobenthos, (3) benthic invertebrate fauna and (4) fish. The classification tools need to assess the composition and the abundance of the biological element (as well as the age structure for the fish classification tool) based on the monitoring results.

Published 1 December 2006