Rural and private water quality trails urban standards

Over a million New Zealanders were supplied with drinking water in 2003 that didn't comply with current standards, according to a survey released yesterday by the Ministry of Health.

The Annual Review of the Microbiological and Chemical Quality of Drinking Water 2003 also found smaller communities lagged behind cities in water quality and monitoring.

The microbiological health risk was assessed during the survey using two criteria: E. coli bacteria and the water-born protozoa, Cryptosporidium.

During 2003, water supplies to 71 per cent of New Zealanders complied with E. coli standards - 2 per cent more than in 2002.

There was a 73 per cent compliance with the treatment plant protozoan requirements, down from 81 per cent the previous year.

The report noted that was almost entirely due to now-resolved problems at a Waitakere treatment plant.

Health Ministry public health engineer Paul Prendergast said in a statement that while 1.1 million people were supplied with non-compliant drinking water, it did not necessarily mean it was unsafe. It meant water suppliers had not demonstrated the water was safe.

"Most of the supplies that didn't comply were from private domestic supplies or small rural supplies that were either not monitored or were monitored inadequately," he said.

"In general, large metropolitan areas and provincial cities are served by supplies that comply with microbiological standards."

The ones that didn't lacked adequate monitoring once E. coli was found, didn't use accredited labs, or supplied water from an unregistered source.

While water-quality standards are the same throughout New Zealand, monitoring is stricter for supplies serving larger populations.

The review also said only 55 per cent of schools with their own drinking supplies conducted some form of bacteriological monitoring.

- NZPA