The report says that there has been a 50% reduction over the past two years but that further investment is needed to bring detection levels in line with other EU countries.

The report reveals that E. coli was detected at least once in 27 out of 944 public water supplies in 2009. This figure is down from 39 in the previous year (2008).

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% of private group water schemes were contaminated at least once during 2009.

The security of water supplies was also covered by the study. This considers the management of the risks from the source water, through the drinking water treatment plant and supply.

339 supplies were identified as needing remedial action in early 2008 and placed them on a Remedial Action List. Of those, 42 per cent (142) have had the necessary remedial work completed.

However, 264 supplies still remained on the Remedial Action List at the end of 2010.

The EPA’s Office of Environmental Enforcement concluding programme manager, Gerard O’Leary, said: “The focused investment in water treatment plants at risk of failing to meet drinking water standards has brought about much needed improvements to our drinking water infrastructure.

“An additional 500,000 people are now served by supplies that have been removed from our Remedial Action List.”

Alison Brown

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