Fifteen hundred households in Co Wexford have been unable to use the local water supply for the last four days. The households affected are supplied by a water source in Kilmallock, 10 miles north of Wexford town.
Residents of Blackwater, Curracloe, Edenvale, Ferrycarrig and their environs have been advised not to use the water because of high levels of ammonia.
The engineer in charge, Mr Niall McGuigan of Wexford County Council, said the increased level of ammonia may have been caused by the heavy rainfall in recent weeks. The prolonged deluge could have dislodged ammonia which occurs naturally in ground water starved of oxygen. However, increases in ammonia levels can also be caused by seepages from slurry tanks and septic tanks.
The supply was turned off last Tuesday, when the water was found to be particularly murky. Supply has now been resumed, but householders have been warned only to use the water for flushing toilets.
Mr McGuigan said he would not be able to advise whether the water was fit to consume until this morning.
"This is very unfortunate, particularly because this is a major tourist area, but there's nothing we can do. Even though the supply has been resumed, I can't say whether the water is clean at the end of the line until I have the results of the chemical and bacteriological analyses on Saturday".
Tankers hired by Wexford County Council have been distributing water to the affected areas. However, local bed-and-breakfasts in the area have had to turn away potential customers.
Residents will be informed through local radio when the water is fit to consume.
