Groundwater Monitoring Programme

Article 8 of the Water Framework Directive requires the establishment of programmes of monitoring for groundwater. The groundwater monitoring programmes primarily focus on providing information that can be used to assess the environmental status of groundwater bodies. Additionally, the groundwater monitoring programmes will provide information to assess whether the environmental objectives of Article 4 of the Water Framework Directive (WFD) are being met, thereby supporting the overall environmental and management objectives within a River Basin District (RBD).

Article 8 of the WFD indicates that monitoring is required to assess groundwater status and that groundwater monitoring programmes must include:

 

Monitoring Network Design

Groundwater monitoring points from existing National groundwater quality and level monitoring programmes, active or abandoned water supplies and known karstic spring discharge features have been assessed to determine their suitability for WFD monitoring and where appropriate, these monitoring points have been integrated into the WFD monitoring programmes.

In groundwater bodies or group of bodies defined as being "at risk" in the Article 5 Characterisation and Risk Assessment Report, the monitoring network is designed to help assess anthropogenic impacts on the flow of water across the groundwater body from recharge to discharge areas and on the flow from groundwater bodies to associated receptors defined as being "at risk". Monitoring in groundwater bodies or groups of bodies defined as being "not at risk" in the Article 5 Characterisation and Risk Assessment Report has been optimised by grouping groundwater bodies where the hydrogeology and pressures are similar.

 

Monitoring Point Representativity

Monitoring locations have been determined by assessing the requirements for achieving a network that is representative of the variations in hydrogeology and pressure across a groundwater body or group of bodies. A representative monitoring network is achieved when the hydrogeology and pressure variations impacting upon a combined network of monitoring points is proportionally similar to the combined hydrogeology and pressure variations over the whole groundwater body or group of bodies in which the monitoring points are located i.e. the average concentrations of diffuse pollutants from a representative network of monitoring points should reflect the average concentrations for those pollutants across the whole groundwater body or group of bodies.

As poorly productive aquifers, by their nature, are generally unable to yield significant quantities of groundwater for abstraction, their quantitative status is unlikely to be impacted upon by abstractions, except where sensitive receptors are affected by localised pumping. In addition, groundwater flow paths are generally short in these aquifers, and consequently water level monitoring is probably only representative of a small area in the vicinity of the monitoring point. Consequently, a dispersed network of monitoring in the poorly productive aquifers would not be beneficial and the monitoring network in poorly productive aquifers is focused on monitoring three scenarios:

  • Groundwater bodies where there are sensitive receptors considered to be "at risk" from abstraction;
  • Major fault zones;
  • Six poorly productive typology settings that take account of many of the different poorly productive aquifer types in the Republic of Ireland.

Monitoring in six poorly productive typology settings has been implemented during the first River Basin Plan period and with installation of piezometers, hydraulic testing and groundwater sampling used to provide information on the hydrogeology.

 

Monitoring Point Source Activities

In accordance with Articles 4, 11 and 17 of the WFD, Member States should assess the effectiveness of Programmes of Measures (POMs) introduced to prevent or limit the inputs of pollutants and/or the deterioration of the status of groundwater.

The proposed water quality monitoring networks will contribute significantly to the assessment of POMs but there may be a need for further additional monitoring, for example, to assess any impact from specific point sources.

Monitoring data from selected compliance monitoring sites e.g. from IPPC licensed activities, will be utilised for the assessment of point source pressures within these groundwater bodies. The compliance monitoring data may be supplemented by additional monitoring in the future e.g. where the monitoring is deemed to be inadequate for WFD purposes or for point source pressures that are not part of the compliance monitoring network.

 

Future Monitoring

There will be ongoing refinement of groundwater body characterisation and risk assessment in response to data gathered from the groundwater monitoring networks and as conceptual understanding of the hydrogeology improves. Regular reviews of the monitoring network will be undertaken to assess the adequacy of the network and ensure the requirements of the WFD are being met. The inclusion of additional monitoring points is already planned for the first River Basin Planning cycle.