Some 5,000 homes and businesses on the east side of Athlone face water supply disruptions this evening.
Irish Water said the unplanned outage of the water supply followed “a pollution event” on the River Shannon close to the intake point to Athlone Water Treatment Plant.
The agency said it was working in partnership with Westmeath County Council to return water supply.
The Irish Water website indicates that it could be 6am on Monday morning before the work is completed and it could be another 2 to 3 hours before water is fully restored to the affected areas.
The areas affected includes approximately 5,000 properties in Ballykeeran, Garycastle, Dublin Road, Athlone Town, Fardrum, Moydrum, Mount Temple, IDA Park, Blyry, Retreat and surrounding areas.
John O'Donoghue, Regional Operations Manager, Irish Water said: “Due to a hydrocarbon pollution event in the Shannon river at the intake point to Athlone Water Treatment Plant, the plant was shut down to minimise the impact to the treated water distribution network.”
“This measure by Irish Water is to prevent the water supply from being contaminated.”
“We are endeavouring to resolve the issue as quickly as possible. It is expected to be resolved by tomorrow morning. Full water service may take some time to return as water refills the network. We wish to thank those affected for their patience and co-operation.”
Irish Water apologised for the inconvenience caused.