The discovery of bacteria commonly associated with faeces has led to a boil water notice for almost 10,000 Irish Water customers in Co Offaly.

The notice was issued on Wednesday evening after routine testing by the Health Service Executive(HSE) found E.coli and Total Coliforms in the drinking water supplies at Birr, Banagher and Dunkerrin.

Irish Water has said further samples are due to be taken in the area on Thursday and the results should be known before the weekend.

“In the interest of public health, all users fed from the three public water supplies must boil their water supply before use,” the company said.

It is working with Offaly County Council and the HSE to ensure that a safe supply of water is returned to the 9,865 customers as soon as possible.

Irish Water said it is directly contacting those individuals on these schemes who have registered as vulnerable customers.

Local TD Carol Nolan of Sinn Féin said there was “general panic” as word spread on social media on Wednesday night.

“No time is the right time, but particularly during the tourism season, it is absolutely putting businesses on the back foot,” she said.

Mrs Nolan wasn’t aware of the source of the pollution or any ongoing works on the water infrastructure in the locality. She said: “I am very concerned like a lot of people, this shouldn’t happen.”

According to local councillor Peter Ormond of Fianna Fáil, “it is going to have an impact on the businesses in the towns in terms of pubs, restaurants.”

He urged people to take precautions and to follow the advice issued by Irish Water. Cllr Ormond said there is some confusion among residents and “in Dunkerrin Village there is three different sources and there is one well that is affected.”

He said people should follow advice and contact the council if they have queries.

He expressed concern for older residents who might not be aware of the issue as many wouldn’t use social media. He urged people to call in to elderly neighbours to ensure they are aware of the situation.

A similar boil notice is in place for over 300 Irish Water customers in Co Wexford. The notice was issued after E.coli and Total Coliforms were detected at low levels during sampling of the Bree public water supply.

Irish Water and Wexford County Council are working with the HSE to ensure that a safe supply is returned to the 365 customers served by the water supply as soon as possible.

The number of Irish Water’s 24 hour customer care helpline number is 1850 278 278 and updates will be available on www.water.ie.