The European Commission has given most Irish beaches and freshwater bathing sites a clean bill of health in its annual report on the state of Europe's bathing waters.
Just four out of 122 holiday beaches in the Republic did not meet the mandatory European standards of hygiene.
Beaches in Balbriggan and Malahide, both Co Dublin, Clifden in Co Galway and Dunmore East in Co Waterford failed the EU test due to concentrations of pollutants such as sewage.
Seven other coastal beaches met the mandatory hygiene standards set by the EU but failed to meet a higher aspirational "guide" level designed to encourage cleaner bathing water.
These beaches are: Spiddal, Co Galway (main beach), Na Forbacha, Co Galway, Sutton (Burrow beach) Dublin, Loughshinny, Co Dublin, Dollymount strand, Dublin, Ardmore, Co Waterford and Enniscrone, Co Sligo.
According to the report, 96.7 per cent of Irish beaches met the mandatory hygiene level in 2006, a slightly better performance than in 2005 when 95.9 per cent met this requirement.
However, the percentage of beaches reaching the "guide" level fell from 91.8 per cent in 2005 to 91 per cent in 2006.
The nine freshwater bathing sites listed by the Irish authorities for inclusion in the EU report all passed the mandatory hygiene levels.
But two sites, Ballyallia, Co Clare, and Keeldra, Co Leitrim, did not meet the more stringent "guide" levels promoted by the commission.
"The situation is getting better with new waste-water treatment plants being built but there are still problems with new buildings being put up and not enough infrastructure to cater for them," said Lucy Hunt, blue flag manager for An Tasice.
"There needs to be more waste-water treatment plants built close to coastal developments."
Across Europe almost nine out of 10 beaches met the mandatory level of hygiene set by the EU.