A new report has found raw sewage is being discharged into 45 rivers, lakes and coastal areas around the country.
The Environmental Protection Agency report shows that more than half of those areas are in Cork, Donegal and Galway.
The report states that some of the worst affected areas include Carrigaline, Crosshaven and Ringaskiddy.
The Urban Waste Water report has also found that waste water discharges are contributing to poor water quality at seven Irish bathing spots.
The bathing areas are Youghal Front Strand, Co Cork, south beach in Rush, Co Dublin, Ballyloughnane and Clifden in Galway, Ardmore in Waterford and Duncannon in Co Wexford.
The EPA warned that the amount of waste being dumped in the water was the same amount as 200,000 people using 140 litres of water a day.