Drinking water in the Kaikōura district fails to meet the government's standards in all but one instance, according to the Ministry of Health.
In its annual report on Drinking Water Quality 2019-2020, the ministry said none of the six water supplies met the standard for bacterial and protozoal counts. And none of the six supplies, apart from Fernleigh, complied with the Health Act.
The results were similar for many other rural councils and Kaikōura District Council (KDC) operations manager Dave Clibbery said they were not unexpected.
"The report does not tell us anything that we don't already know KDC's non-compliance with these standards has not been because there is any evidence of water contamination."
The reason was that the council's water treatment plants did not incorporate all of the processes required by the drinking water standards and/or monitoring, and reporting did not exactly conform with the stipulated requirements, Clibbery said.
"The frequency of sampling required depends on the number of people connected to the supply, but some of the frequencies are high even for supplies that are relatively small."
For example, some of the parameters for the Kaikōura supply such as the level of chlorine and the turbidity (clarity) of the water had to be automatically monitored at three-minute intervals, Clibbery said.
"A single result that is outside of the permitted range - even if it is an incorrect result - can make the supply fail to meet the standards for that year."
KDC was continuing to upgrade water supplies to enable compliance with the drinking water standards, Clibbery said.
"The solution to current non-compliance lies in upgrading treatment processes and using technology to improve monitoring.
"But the type of advanced technology that might be quite affordable for a large town's water supply becomes financially challenging for small supplies such as those of KDC and the many other rural councils."
Funding provided by the Department of Internal Affairs to support the Three Waters reform process was helping KDC to do that work, but once it was completed there would be higher ongoing operational costs, that would have to be met by the community, Clibbery said.
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