Almost a third of rivers and streams in the Republic are polluted, a study revealed today.
The Environmental Protection Agency (EPA) report on water quality said run-off from waste treatment plants and farms was the main cause of pollution in rivers, lakes and coastal seas.
It also found human or animal effluent was detected in more than half of the groundwater locations, such as springs, sampled around the country.
The comprehensive three-year review studied the conditions in some 13,240kms of river and stream channel (1,151 rivers), 449 lakes, 69 estuarine and coastal water bodies and 137 groundwater-monitoring stations from 2004 - 2006.
It found 29 per cent of river length is polluted to varying degrees, a slight improvement on previous years, and that 66 lakes and 15 estuarine bodies were deemed to be of unsatisfactory quality.
The EPA said while there was evidence of an overall improvement in water quality, the rate was not enough to meet a 2015 target under the Water Framework Directive.
Dr Jim Bowman, of the EPA, said the main restorative measure required for surface waters is controlling and reducing waste in to these waters.
"Proper management of groundwater resources is needed in order to prevent pollution of groundwater sources, maintain the quality and yield of drinking water from these sources, and ensure that groundwater is not having a
detrimental impact on surface water and ecological receptors," he added.
The report revealed serious pollution in rivers and streams reduced to 63.5kms, its lowest level in recent decades, and almost 92% of lakes examined were deemed to be satisfactory.
A marked reduction in the number of fish kills was also recorded.
But nitrate concentrations were significantly above natural levels in rivers and streams in several areas, particularly in the south-east and south.
Minister for the Environment John Gormley said the government was fully committed to the challenge of improving water quality.
"Water is a very precious resource and we must do everything in our power to protect and conserve it," he said.
"We have made some progress in the area of water quality in recent years but a lot more needs to be done.
"Unfortunately, our rivers, lakes and water sources are still under threat from pollution and we must protect them."
PA