Thursday, 17 December 2009

Dramatic decline in high quality river sites during the last 20 years

The EPA has released its latest report on key indicators of the aquatic environment - Water Quality in Ireland 2007 - 2008 - which summarises the most recent national water quality assessments.

The report presents the most up-to-date data available in Ireland on the 20 most relevant and important indicators of water quality. It includes, for the first time, interpretation of the significant monitoring data collected under the Water Framework Directive (WFD). The statistics, summarising the monitoring results for surface and groundwaters for the period 2007 - 2008, show recent increases in fish kills and pollution at sea incidents, decreases in the number of bathing water sites meeting EU standards and a dramatic loss in the percentage of high ecological river sites over the last 20 years.

Key Findings
30% of the rivers sampled were of high ecological status in 1987. By 2008, this has dropped to 17%, located in less densely populated, less developed and less intensively farmed areas. The suspected causes of this dramatic loss are nutrient inputs, siltation and acidification associated with activities such as forestry, agriculture and housing development.

New Water Framework Directive classification systems
The WFD requires a new classification system for water quality assessment that covers a wider range of data. This new classification system - high, good, moderate, poor and bad is determined by assessing data on -

* biological quality - plankton, invertebrates, plants and fish;
* physico-chemical characteristics;
* specific pollutants - and
* water flows and other physical characteristics.

Using the new and more demanding Water Framework Directive status assessment system, good or high status was assigned to -

* 49% of rivers
* 55% of lakes - and
* 60% of estuarine and coastal waters.

85% of groundwaters were in good status.

These figures indicate that almost half of the river and lake water bodies - and 40% of the estuarine water bodies - examined are in a condition that will require remedial measures to restore these waters to ensure compliance with the requirements of the Water Framework Directive.

Commenting on the findings of the report, Dara Lynott, Director, EPA Office of Environmental Enforcement said - “The scale of the task of achieving the objectives of the Water Framework Directive is now becoming clearer. In addition to applying protective measures to those sites assigned high and good status, almost 50% of river and lake waterbodies will require restorative measures, while 40% of estuaries and coastal waters will also need to be restored.”

Deterioration of groundwater quality is also a major cause for concern. The level of bacterial and nutrient contamination in our groundwaters is increasing and faecal coliforms were detected in more than half of the groundwater locations sampled.

According to Dr. Jim Bowman, Programme Manager of the Aquatic Environment programme in the EPA - “Nutrient enrichment of surface and groundwater remains at a high level, with municipal and agricultural discharges being the key contributors. The dramatic decline in the number of high ecological quality river sites during the past 20 years - largely due to low level enrichment and siltation in upland areas - is unacceptable and will have to be addressed.”

Dr Bowman added - “A major challenge to be confronted in the immediate future is to protect our remaining high status waters and restore those that are degraded.”

The Water Quality in Ireland 2007-2008 report deals with -

* 13,200km of river and stream channel;
* 433 lakes;
* 89 tidal water bodies - and
* 275 groundwater sources.

As well as giving the present situation, regarding the state of the aquatic resource, the report also includes analyses of trends over time. Only by including historical information can improvement or deterioration be discerned and programmes of measures for remediation be instituted.

The report is also available from the EPA’s Publications’ Office, McCumiskey House, Richview, Dublin 14 - Tel: 01-2680100.

Report Findings

Surface Waters

* 70% of river channel length and over 90% of lake surface area examined were of satisfactory water quality.
* 84% of estuarine/coastal water bodies examined were in an unpolluted or intermediate state. 8% were potentially eutrophic with a further 8% eutrophic (over-enriched).
* The percentage of high ecological quality river sites in the country has almost halved in the period since 1987. (High ecological quality river sites are indicators of largely undisturbed biological communities and reflect the natural background conditions, or only very minor distortion by human influences).
* The number of fish kills, while reduced compared to 2006, remains at an unacceptably high level with 22 in 2007 and 34 in 2008.
* The overall water quality in canals remains good.


* Nitrate concentrations in rivers in the south and south-east regions were generally higher than elsewhere in the country.
* Nitrate concentrations for 92% of lakes were in the low category.
* 40% of estuarine and coastal waters had excessive nitrate concentrations in winter.
* Phosphate concentrations in 71% of rivers and 81% of lakes were consistent with good or high status.
* 24% of groundwater monitoring locations were classified as being in less than good status based on mean phosphate concentrations.

Water Framework Directive Status Assessment

* 49% of rivers, 55% of lakes and 60% of estuarine and coastal waters were assigned good or high status using the new Water Framework Directive classification systems.


* 67% of the groundwater well and spring sampling locations had faecal coliforms in at least one sample.
* Approximately 7% of the groundwater locations examined exceeded the national guideline value for nitrate concentration for drinking water, with 1% breaching the mandatory limit.

Bathing Water

* The overall quality of the bathing waters in Ireland, while showing some deterioration in 2008, remains good.

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