Carterton District Council (CDC) has placed an indefinite boil water notice on the town supply after another positive reading for the deadly E coli bacteria.

Council contractors, regional public health experts, and external senior water engineers are working to identify the source somewhere in the town’s system.

More than 4000 people rely on the network for drinking water.

The sample of one MPN (most probable number) unit per 100ml breaches national drinking water standards, which calls for less than 1MPN per 100ml.

CDC infrastructure, services and regulatory manager Dave Gittings said the council had taken remedial action since the first elevated E coli reading last Friday but the source of contamination remained elusive.

“We’re not getting elevated E coli readings out of the bores or the Kaipatangata supply, and we have had clear samples every day since last Friday,” he said.

“We’re doing everything we can to identify the source, and we will hold the boil water notice in place until we’re confident we’ve done this and eliminated the low-level E coli bacteria.”

The council reported two other results of the bacteria in December and January.

The Carterton outbreak is the latest of a long list of similar water troubles in Wairarapa.

Martinborough suffered two similar scares in 2019, leading to chlorination of the town supply.

The final part of the safeguarding system, a manganese removal plant, officially opened last week.

Last June, Featherston residents were urged to boil their drinking water after storm damage to supply pipes.

Later that year, residents of the small South Wairarapa hamlet of Pirinoa received boil water notices.

In November 2020, the private Opaki water scheme returned a positive E coli reading.

Contact your doctor or call Healthline (0800 611 116) if you have been in the Carterton area and suffer diarrhoea, vomiting, and/or a fever.

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