Diseases in NZ drinking water common, says health adviser

Outbreaks of water-borne illness are often hushed up and are more common than most people believe, says Ministry of Health senior adviser Michael Taylor.

Dr Taylor last week witnessed the graduation of the first 30 people to achieve the national diploma in drinking-water assessment.

The Otago Polytechnic graduates, mostly from district health boards, will return to their communities to help to meet new standards for drinking water safety, soon to become law in the Health Amendment Act (Drinking Water).

All water suppliers will have to meet national water standards and develop risk management plans.

Dr Taylor said the graduates would help to prevent the equivalent of a leaky building crisis hitting the nation's drinking water.

The building crisis highlighted the absence of national standards for building inspectors, he said. Those responsible for drinking water had been in a similar position, as no one had replaced the role the Ministry of Works played until the mid-1980s.

In the meantime, outbreaks of water-borne disease had continued to strike some of the country's more than 2500 water supplies.

Last year campylobacter got into the drinking water at a Hawkes Bay school, but as only two of those affected had samples taken for analysis, the event almost slipped under the authorities' radar.

"This is the problem throughout New Zealand - people tend to hush these things up," Dr Taylor said.

Cryptosporidium and giardia had been responsible for other outbreaks, he said.

"We know 78 per cent of the population has safe water." Of the rest, 4 per cent was known to be unsafe and the rest of unknown quality.

It took three days to test for the pathogen cause of most water-borne diseases, he said. That meant in one recent case involving South Island skifield Mt Hutt, it had been difficult to trace the illness to the source because those affected were long gone.

"You can make an awful lot of people sick in three days."

The new requirements would be difficult for small rural water schemes, which would face a cost of up to $500 a customer, but the ministry was looking at ways of helping them, Dr Taylor said.

- NZPA