Local authorities responded inadequately to more than a third of serious water contamination incidents last year, the EPA water quality report for 2000 says.
The agency was concerned at the response to 24 out of 66 serious incidents of bacterial contamination by faecal coliforms, such as E.coli, originating from human and animal waste.
Water quality in these 24 cases was not retested within seven days "which would indicate that corrective actions were not taken within sufficient time to address the urgency of the situation". No follow-up action was reported for three incidents of serious faecal contamination in public water supplies at Clashanamid (Cork South), Shanbally (Galway County) and Lauragh (Kerry).
The report states: "The bacteriological quality of drinking water is the single most important characteristic as far as the general health of the public is concerned. It notes that local authorities "address exceedances of the drinking water standards using informal or ad-hoc procedures".
Furthermore, "random audits of local authorities by the EPA indicate that in some instances corrective actions were not always put in place as a result of values found to be in excess of drinking water standards", said the report.
As a result, the EPA will be "pushing local authorities harder", said Mr Gerard O'Leary, senior scientific officer, EPA, one of the report's authors.
A pilot scheme which comprehensively monitored group water schemes in Co Roscommon needs to be extended to all counties, said Mr O'Leary. This scheme monitored levels of faecal coliforms each month. Group water schemes are typically monitored once a year and often on a three-year cycle, which is insufficient, the authority says.
A "disturbing feature" which emerged in the report was that "all drinking water quality data was not returned by the local authority to the EPA".