The Prison Service is having to spend more money on bottled water at Castlerea Prison because of problems with the local water supply.

A boil water notice was re-issued for the Roscommon town earlier this year meaning over 21,000 people across the county cannot drink water directly from the tap.

Over €5,000 has been spent on bottled water at the prison since February.

The average household in the area is expected to face a bill of up to €1,000 for bottled water if the restrictions are in place all year.

Meanwhile the cost to the Prison Service could be over €20,000.