EU Water Framework Directive : groundwater-dependent terrestrial ecosystems in Northern Ireland

Abstract

The EU Water Framework Directive (WFD) requires those terrestrial ecosystems dependent on groundwater be identified and the anthropogenic pressures acting on the ecosystems analysed. Where significant damage is occurring or could occur due to groundwater factors, then the associated groundwater body is considered to be at risk of not attaining ‘good status’ as defined in the Directive. This report describes the methodology for identifying and carrying out risk assessments for groundwater-dependent terrestrial ecosystems (GWDTEs) in Northern Ireland as part of the initial characterisation process of the WFD. The methodology is based on UK Technical Advisory Group (UKTAG) guidance. 22 designated sites, all Special Areas of Conservation (SACs), have been identified in Northern Ireland as GWDTEs. The report details the level of risk to these GWDTEs from groundwater abstractions and potentially polluting point sources. With one exception, the occurrence of both types of groundwater pressure within the assessment zones of the GWDTEs set by the UKTAG guidance is negligible and hence Risk Category 2b has been determined for initial characterisation. Murlough SAC has been given a Risk Category of 2a for potentially polluting point sources, i.e. it is not at significant risk but confidence that the available information is comprehensive and reliable is low. This is because there are a number of controlled point sources on or close to the GWDTE, on geology that is likely to be in hydraulic connection with it, and some of these sources are concentrated in a small area. It is suggested that improved monitoring of this site would be advisable to increase confidence in the risk assessment. The report highlights a number of aspects that could improve the methodology for identification and assessment of risk for GWDTEs