Water Quality in Ireland Report 2001-2003

Date released: Jun 13 2005

Overall Ireland's water quality remains of a high standard according to an Environmental Protection Agency report entitled 'Water Quality in Ireland 2001-2003'.

Eutrophication (over enrichment) of rivers, lakes and tidal waters continues to be the main threat to the State’s surface waters with agricultural run-off and municipal discharges being the key contributors.  Gains made in the late 1990s in reducing the extent of rivers affected by over-enrichment have not been sustained.  Both point and non-point waste sources are contributing to the problem. Of the two, non-point sources, particularly inputs from farm land, are likely to be the more difficult to control, the report states.  Implementation of the national Action Plan under the Nitrates directive should lead to a reduction of nutrient losses from farm land.

The detection of faecal coliforms in samples from a considerable number of locations remains a concern in relation to groundwaters. This is likely to be due in most cases to non-point waste sources and should benefit from measures taken to counter the pollution of surface waters by such sources.

This comprehensive review deals with the conditions in some 13,000 km of river and stream channel, 500 lakes, 69 individual tidal water bodies located in 25 estuarine and coastal water areas and 300 groundwater sources. 

Summary Findings

Rivers & Streams

  • Serious pollution in rivers and streams has reduced to just 76 km (0.6% of surveyed channel), its lowest level since the early 1990s. Most of the serious pollution is considered to be caused by municipal discharges.
  • Some 30 per cent of the river and stream channel surveyed in the period is classed as moderately (12.3%) or slightly (17.9%) polluted – attributed mainly to eutrophication.  While gains were made in the late 1990s in reducing the extent of such pollution, no further progress was made in the 2001 to 2003 period. The main suspected causes of this pollution are agricultural wastes and municipal discharges.
  • Overall there has been a slight reduction in the proportion of unpolluted channel, down 0.6 per cent to 69.2 per cent.
  • Nitrate concentrations are significantly above natural levels in rivers and streams in several areas, particularly in the south-east and south.
  • The available data indicate that the levels of potentially dangerous substances are generally insignificant.


Findings regarding lake water quality were encouraging.

  • Ninety one per cent of the total area of lake water examined was deemed to be in a satisfactory condition, showing natural or only slightly enhanced levels of algal growth.
  • Although open waters in the large western lakes showed low or moderate levels of planktonic algae, instances of excessive algal growth occurred closer to the shore.
  • Highly eutrophic or hypertrophic conditions continued to affect some lakes including Loughs Sheelin, Oughter, Gowna and Ramor.
  • The designated fresh water bathing areas (all of which are situated on lakes) showed full compliance with national regulations.

Estuaries and Coastal Waters

  • Of the 69 tidal areas assessed for eutrophication, 78 per cent were classed as unpolluted or showing only slight signs of eutrophication. 
  • Eutrophic conditions were shown by 12 of the remaining 15 water bodies while the other three were classed as potentially eutrophic.
  • Areas experiencing eutrophication included: the upper and lower Bandon Estuary, the lower Slaney Estuary and south Wexford Harbour.
  • Marine Institute data show that the levels of toxic contaminants in fish and shellfish harvested from tidal waters remained low and within the limits set for the protection of consumers. However, the assessment of the sanitary conditions in shellfish waters again shows a requirement for purification of live molluscs before sale, as a result of faecal coliforms.
  • Monitoring of radioactivity in the marine environment by the Radiological Protection Institute shows that the relatively low levels recorded over the past decade have been sustained, in contrast to the much higher levels recorded in the 1970s and 1980s.
  • The Irish Coast Guard received 148 reports of pollution in the period, with mineral oils comprising the bulk of the polluting material observed. In most such cases, the offending vessel could not be identified. However, potential oil pollution due to marine accidents was successfully averted by containment measures in most instances.


The monitoring of groundwaters was based on biannual sampling at times of high and low water table levels. Of particular interest were those parameters indicative of the suitability of the groundwater as a source of drinking water.

  • Faecal coliforms were detected in 22 per cent of all of the samples analysed (down 16% on the previous period).
  • Nitrate concentrations exceeded the drinking water guide limit in 23 per cent of the samples of groundwater analysed and in 2 per cent of the samples the concentrations were above the mandatory limit. 
  • The detection of significant concentrations of uranium in some groundwaters in 2001 led to a wider screening for the metal by the EPA. The bulk of the samples taken were well within the proposed WHO limit for drinking water.   In a small number of cases concentrations were well above this level and water supply sources for certain schemes were changed as a consequence.    However, a study conducted by the Health Services Executive on the impact of a groundwater source in Wicklow with high uranium levels did not show the presence of effects in the consumers.

Water Framework Directive

The Directive was brought into Irish law by regulation in December 2003. Its main requirements include:

  • the attainment of good quality in all waters by 2015,
  • the management of waters on a River Basin District (RBD) basis, 
  • the elimination of the discharge of certain harmful substances to waters
  • and the sustainable use of water resources.

There are seven River Basin Districts: four (Eastern, South Eastern, South Western and Western) wholly within the State and three (North Western, Shannon and Neagh-Bann) are designated as International RBDs shared with Northern Ireland.

The main initial task was the preparation of the Characterisation Report which deals with the physical, chemical and biological nature of the surface and ground waters in the River Basin Districts as well as an assessment of the human impact on these waters. The report was completed on schedule by the relevant authorities in December 2004 and a summary was submitted to the EU Commission by the EPA in March 2005.

Future tasks include the formulation of monitoring programmes and the identification of the measures needed to ensure the attainment of the good quality objective by 2015.