There has been a 50 per cent reduction in the detection of E.coli in local authority drinking water in the last two years, a new report has found.
The Environmental Protection Agency (EPA) study found that E.coli bacteria, an indicator of whether human or animal waste has entered a water supply, was detected on at least one occasion in 2.9 per cent of public water supplies during 2009.
This equates to a finding of E.coli once in 27 samples out of 944 public water supplies, down from 39 in the previous year.
In Ireland, 85 per cent of drinking water comes from public or local authority water supplies, with the remainder coming from group water schemes and private supplies.
The report found the number of private group water schemes where E.coli was detected dropped from 134 in 2008 to 87 in 2009.
However, despite this improvement, 17 per cent of private group water schemes were contaminated at least once during 2009. The EPA was assigned powers to supervise the quality of public drinking water supplies in 2007, including powers of enforcement against local authorities should the quality be deficient.
In conjunction with the Health Service Executive, boil water notices or restrictions on use were put in place on 53 supplies serving approximately 93,000 persons in 2009, with adverse weather conditions in November 2009 leading to the imposition of boil water notices on 10 public supplies.
Of 339 water supplies listed by the EPA for remedial action in 2008, 142 have been remedied.
