How will groundwater bodies be classified?

Groundwater bodies will be classified for two parameters:

• Quantitative status (good or poor depending upon the groundwater level regime); and
• Chemical status (good or poor depending upon the conductivity and concentrations of pollutants).

Groundwater status will be assessed through a combination of monitoring data, conceptual models and pressure data (pressures impacting upon the groundwater body (GWB)) to determine whether the GWB is in good or poor quantitative or chemical status. In the assessment of chemical status, different threshold values may be set by Member States for each GWB taking into account the pressures that are present and the uses of the GWB. They can be established at the national, River Basin District or water body level.

Clear guidance will be needed to set out the threshold setting process. However, EU-prescribed standards already exist for nitrates and pesticides. If these values are exceeded, then an investigation is triggered to confirm whether the GWB is at good status. Various tests are under development to classify groundwater quantitative status and groundwater chemical status respectively. The criteria for these tests derive from the WFD, plus for chemical status, additional requirements set out in the Groundwater Daughter Directive. (In the absence of the finalised directive, the criteria have been taken from the EU Council Common Position.)