Drinking water fails to make grade

More than a million New Zealanders are drinking water which is either not up to standard or not being monitored properly, according to a Ministry of Health review issued yesterday.

The findings were released in the Annual Review of Drinking-Water Quality in New Zealand in 2004.

The review assessed the microbiological health risk in water from Escherichia coli bacteria and the water-born protozoa cryptosporidium. It also looked at the chemical composition of drinking water.

During 2004, water supplied to 74 per cent of the population complied with the E coli criterion for drinking-water standards, a 3 per cent improvement compared to the previous year.

There was a 71 per cent compliance with the cryptosporidium criterion, which is a 7 per cent improvement since 2003. That represents 120,000 more people with access to good-quality drinking water.

However, about 1.04 million New Zealanders were supplied during 2004 with water that either failed to comply bacteriologically with the Drinking Water Standards for New Zealand 2000 (DWSNZ:2000) or their water was self-supplied.

The causes of the non-compliance centred on the most part on levels of E coli or a failure by water suppliers to take appropriate action, including monitoring after it had been found.

Some took insufficient samples during the year to demonstrate E coli compliance and other water suppliers did not use accredited labs for testing, or supplied water from an unregistered source.

The Ministry of Health's principal public health engineer, Paul Prendergast, said 1.04 million people did not necessarily receive unsafe drinking-water during 2004 - it simply meant water suppliers did not demonstrate the water was safe.

"Most of the non-compliant supplies were from small rural water supplies or domestic supplies that were either not monitored or inadequately monitored," he said.

The review also found that four hospitals or health services that were not connected to municipal drinking-water supplies failed to comply bacteriologically with the drinking-water standards.

School drinking water also needs improvement. During 2004, 57 per cent of the 640 schools with their own water supplies conducted some bacteriological monitoring, a 2 per cent improvement on 2003.

Of the school water supplies monitored, 84 (13 per cent) complied with the bacteriological criteria of the drinking-water standards, 1 per cent down on the previous year. 

- NZPA