Dog poo is the most potent pollutant on Dublin beaches according to a report from Dublin City Council.
According to the council's environmental protection division, dog fouling was the most common cause of bathing water failures and prohibitions during last year's season.
Dublin City Council tests water quality at designated swimming areas on Sandymount and Dollymount Strand throughout the bathing season which begins on June 1st and ends on September 15th.
Green Party Councillor, Donna Cooney says the bathing season should be extended to year round to give swimmers peace of mind:
"We had a pilot where the tertiary treatment, which is ultra-violet treatment, was used up to December in Irish water and that was a really good thing.
"I think that should be extended.
"I think we should have year-round bathing water, particularly in areas where people swim a lot."
More dog wardens could also be patrolling beaches this summer to catch people not cleaning up after their pets.
However it's often hard for them to issue fines to owners as they have to catch them in the act.
In the past 5 years just 27 fines were issued in Dublin city for dog fouling.