IMPROVING THE status of all of Ireland's water bodies to good quality by 2015 will prove a demanding target because of continuing problems with pollution and eutrophication in rivers, lakes, estuaries and groundwater.
The section on water in the EPA's state of the environment report concludes that the majority of water bodies are in satisfactory condition but raises concern about pollution in other waters.
In particular, it expresses some doubt about meeting targets set out by the EU Water Framework Directive that the ecological and chemical status of all water bodies will be good by 2015.
"The targets are likely to be very demanding in many cases, especially in waters where there is a long history of pollution, or as with some surface water, physical disturbance," it says.
Management of water in Ireland has changed in recent years, with the gradual transition towards river basin management plans. There are eight river basins on the island of Ireland.
A total of 13,240km of river channel was surveyed. Some 71 per cent was found to be satisfactory, a 2 per cent increase since the last report in 2004. The best two river basins were in the southwest (with 90 per cent unpolluted) and the west (84 per cent).
Some 18 per cent was found to be slightly polluted; 10 per cent was moderately polluted and 39 rivers (or 0.5 per cent) were seriously polluted. This was a reduction of 10 rivers since the last report in 2004, when 49 rivers were seriously polluted.
The rivers include the Avoca in Co Wicklow, which has been subject to acid mine leachate since the 1850s; the Triogue below Portlaoise, Co Laois; the Tullamore river in Co Offaly; Tully river in Co Kildare; the Lower Camac and Tolka rivers in Dublin, and the Brosna in Co Westmeath.
Some 66 lakes (or 14.7 per cent) were found to have less than satisfactory water quality.
The report notes that there has been no major change for lakes since 2004, though 38 lakes have deteriorated in status since then.
"The main pressure is inputs of nutrients like phosphate and nitrogen at concentrations in excess of natural levels, resulting in over-enrichment and eutrophication. It leads to increase in planktonic algal and higher plant biomass and an undesirable disturbance of the balance of organisms," the report states.
It also notes that zebra mussels have colonised some lakes and are present in 33 lakes: "The continued spread of zebra mussels and of other invasive alien species is a cause for concern," it states.
Coastal waters have fared much better by comparison. "The extensive offshore areas are generally not affected by pollution, while inshore, water qualities in most estuaries and coastal waters remains high."
However, the report continues: "A number of estuaries, however, mainly in the southeast and south of the country, continue to display nutrient enrichment and have been classed as eutrophic."
The quality of bathing water is high and the EPA attributes this in part to the huge success of the Blue Flag beach scheme.
The report also finds that radioactive substances from the nuclear reprocessing plant in Sellafield continue to be discharged into the Irish Sea although without posing a significant health risk.
It concludes commercial fishing is occurring at an unsustainable level, with most stocks in decline and cod stocks in collapse. It notes that climate change will have an impact in this sector in future, through rising sea levels, storms and acidification of the oceans.
Ground water, which makes up 26 per cent of drinking water, has seen slight increases in nitrates and phosphates between 1996 and 2006 with elevated nitrate levels in east and southeast of Ireland.
The EPA says 61 per cent of groundwater is at risk of deterioration from farming effluent, dangerous substances, nitrates and phosphates.
The Irish Times