Classification

The WFD classification scheme for water quality includes five status classes: high, good, moderate, poor and bad.

‘High status’ is defined as the biological, chemical and morphological conditions associated with no or very low human pressure. This is also called the ‘reference condition’ as it is the best status achievable - the benchmark. These reference conditions are type-specific, so they are different for different types of rivers, lakes or coastal waters so as to take into account the broad diversity of ecological regions in Europe.


Assessment of quality is based on the extent of deviation from these reference conditions, following the definitions in the Directive. ‘Good status’ means ‘slight’ deviation, ‘moderate status’ means ‘moderate’ deviation, and so on. The definition of ecological status takes into account specific aspects of the biological quality elements, for example “composition and abundance of aquatic flora” or “composition, abundance and age structure of fish fauna”

Data from the Irish Water Framework Directive (WFD) monitoring programmes for Groundwater, Rivers, Lakes, Transitional and Coastal Waters are used by the Environmental Protection Agency (EPA) to determine status for all water bodies.

Water status results for all water categories are available to view as maps or to download from the Agency’s Geo Portal. The available information provides details on the overall status of individual water bodies and also the assessment results for different quality elements e.g. chemistry, macroinvertebrates, plants, fish, hydromorphology, etc.

Learn More

Further detail on the monitoring programme

Further detail on the classification of groundwater and surface waters

Further detail on the assessment methods for classifying groundwater bodies

Publications about Water Quality in Ireland