Local authorities and water groups have defended the record of small rural schemes following criticism in yesterday's drinking water quality report.
The report by the Environmental Protection Agency found continuing problems with group water schemes serving more than 50,000 rural homes, with 25 per cent in breach of faecal coliform limits.
However, Sligo County Council, which found the highest levels of contamination for any local authority area, said it was envisaged that all drinking water schemes in the county would meet quality standards within 18 months.
The EPA report found that over 50 per cent of group water schemes in Co Sligo were contaminated with faecal coliforms, caused by animal or human waste.
Ms Kathleen McTiernan, of Sligo County Council, said the report failed to reflect the major upgrading work for the smaller group supplies.
More than 10 of the small groups will be linked into two new water treatment plants, she said.
"We're working very hard on this, and we're way ahead of other counties. Within 18 months all of the drinking water schemes in the county will be compliant with the limits."
The National Federation of Group Water Schemes also defended the work being done by its members.
The federation's chairman, Mr Brendan O'Mahony, said "he accepted that the quality of drinking water on many group water schemes remains unacceptable."
However, it was "important to reassure consumers that huge strides are being made towards resolving this problem".
Meanwhile, the IFA has rejected a key recommendation made by the EPA for the introduction of new agricultural by-laws to protect against water pollution from farm and industrial sources.
The EPA found that nearly 40 per cent of Irish rivers had phosphorus levels in excess of the national limits.
The IFA's environment committee chairman, Mr Tom Dunne, said farmers were "already highly regulated through good farming practice requirements.
"In addition, almost 40,000 farmers participate in the Rural Environment Protection Scheme and have entered into binding contracts with the State to farm in an environmentally friendly manner and protect heritage."