Skip the NI Direct Bar
Department of the Environment logo
Northern Ireland Environment Agency logo
Home > NIEA > Water Home > Water Resources > Groundwater

Groundwater in Northern Ireland

Last updated: 14 October 2009

Groundwater can be found beneath most parts of Northern Ireland and forms an integral part of its water cycle. It is contained within geological deposits beneath the ground with the water stored in pore spaces between mineral grains and/or within fractures and cracks in the rock itself.

Groundwater is an important natural resource that supports river flows as well as ecological diversity in rivers, lakes and wetlands. It is also available for use for water supply by abstraction from boreholes, wells and springs.Groundwater

The natural chemistry of groundwater is influenced by a variety of factors such as the type of rocks it flows through, or its proximity to coastal salt waters.

Generally, groundwater in its natural state is of good quality as the soils and rocks it moves through act as filters. However, groundwater quality can be affected by a wide variety of land use such as the over-application of nitrates and pesticides, leaks from hydrocarbon storage tanks, contaminated land drainage, or poorly sited, or constructed, septic tanks.

Pollutants can be either chemical or microbiological and the deterioration of groundwater quality can impact on those rivers and lakes into which the groundwater discharges.

Groundwater quality is routinely sampled and tested using a network of 90 boreholes and springs across Northern Ireland: Northern Ireland groundwater monitoring strategy Sept 2000(.PDF 723Kb)Opens in New window.

Data collected is used to assess compliance with European legislation such as the Nitrates (91/676/EEC) and Groundwater (80/68/EEC) Directives.

The Regional Groundwater Monitoring Network (Northern Ireland) annual review reports are as follows:

The Water Framework Directive (2000/60/EC) contains specific monitoring requirements for groundwater. The existing network will be modified to make sure standards are met.

Guidance notes on matters relating to groundwater management and protection include:

Guidance notes on matters relating to groundwater management and protection include: