Swimmers will learn today if they will be able to take a dip in a popular south side bathing spot.
White Rock Beach in Killiney was closed on Wednesday when a water test discovered a high level of E coli.
The bathing spot was tested on Monday and the cause of the increased levels of the bacteria is not yet known.
Another sample has been taken from the beach and we will find out today if it can be reopened to swimmers.
Dun Laoghaire Rathdown County Council says that an investigation has started to get to the root of the problem.
Last July the same beach was closed to swimmers due to similar concerns.
E coli can result in diarrhoea, stomach cramps, nausea and vomiting.
