Martinborough’s boil notice was lifted last week, three weeks after the town’s water supply was found to have low level E.coli contamination.
The notice was lifted after three consecutive clear tests.
But South Wairarapa District Council has also decided to bring forward the installation of a manganese extraction plant to allow for possible chlorination of the town’s water in future.
Martinborough is the only Wairarapa town which doesn’t use chlorine.
Because the town’s water contains manganese, adding chlorine would turn it “coffee brown”.
A report to the council suggested the installation of a manganese plant to remove suspended manganese from the water supply.
Chief executive Paul Crimp said the “only way to prevent the last three weeks happening again” was to start the plant and chlorinate.
“My request for the health of the community is that we do the one thing that council can which is chlorinate.”
Crimp said it would take nine months for the council to set up a manganese plant with capital costs estimated at $485,000. Chlorination could follow the establishment of a plant.
He said it was important to start the process now and the council could decide on chlorinating later.
“Just because we remove the manganese does not mean we have to chlorinate.”
There was concern about how chlorination would impact Martinborough winemakers, with councillors Ross Vickery, Pip Maynard and Lee Carter raising similar points, including how it would affect taste and some vineyards’
Vickery said, “the best outcome for the urban supply might not be best for the vineyards”.
Councillor Colin Olds said public health was the more important consideration.
“Human health is a hell of a lot more valuable than the health of the vineyards.”
Mayor Viv Napier said drinking water standards would be changed by the Government in June and mandatory chlorination seemed likely.
“We may not have a debate about [chlorination], it may be compulsory.”
The installation of a manganese plant was consulted on as part of the council’s 2018/2019 Long Term Plan.
The council voted in favour of advancing the installation of a manganese plant for the Martinborough water supply from 2021 to this year – the only opposition vote came from councillor Lee Carter.
“I’m not opposed but need more information,” she said. “I’m concerned we’re making these decisions without [knowing about] other alternatives.”