More children than ever are being exposed to contaminated drinking water at country schools, according to a Government survey.

This is despite a Ministry of Education campaign to improve school drinking water, including paying for better treatment systems.

In the Ministry of Health's survey of drinking-water quality, published yesterday, only 55 of the 642 rural schools supplying their own water were shown to have complied with the bacterial standards.

The previous year the number was 83, out of 633 schools.

Fewer than half the schools took water samples for testing.

To comply with the national drinking water standards, the water must be regularly tested and be free of E-coli.

"The results are quite disappointing," said Ministry of Education spokesman Brian Mitchell.

His ministry had spent $2.8 million in the past three years on improvements to water systems.

The report said the high incidence of E-coli was probably because:

* Half the supplies were roof water, which could be contaminated by bird faeces.

* Many schools treated their water with ultraviolet-light systems, which were often poorly maintained.

Legislation due before Parliament this year provides for fines of up to $200,000 for failing to do everything reasonable to comply with water standards.

Herald feature: Health