A "boil water" notice has been issued to residents in the seaside village of Glenbeigh, Co Kerry, after the HSE detected the bacterium E.coli in water supplies.
The summer's heavy rainfall has increased the risk of E.coli in water supplies, a senior county council water services engineer warned yesterday.
Ger MacNamara said a random check by the health authority which identified the bug was carried out earlier this week and the county council was informed immediately.
He said the council in turn immediately checked for chlorine levels, which is used to eliminate E.coli.
Glenbeigh is served by three sources and in one of these the chlorinator was found not to be functioning. The boil notice, applying to drinking water, was issued straight away. The chlorinator has now been repaired and the boil notice is expected to be lifted within days.
Mr MacNamara said this was the first such notice to be issued in Kerry this year.
He added that because of the two months of practically non-stop rain, the risk of E.coli getting in to water supplies had increased greatly.
The bacteria is found in animal intestines and waste and if ingested can cause severe diarrhoea and vomiting in humans.
"The more it rains, the more it gets washed into lakes and rivers," Mr MacNamara said.
The increase in population in summer in Kerry also meant more water was being used.
Some €26 million is needed urgently to upgrade water supplies in the county; a request covering about 60 different schemes is before the Department of the Environment.
Development has been halted or curtailed in a number of towns because of the inadequate water supply and water treatment in the county.