Christchurch to be 'forced' to chlorinate remainder of water supply, mayor says

Tuesday, 16 May 2023

Christchurch mayor Phil Mauger says the city has been told to go “over and above” Government standards if it wants to be chlorine-free.

Christchurch’s water supply may become permanently chlorinated after the national water regulator indicated it will reject the city council’s exemption applications.

In 2022, the Christchurch City Council applied to Taumata Arowai for chlorine exemptions, but on Tuesday was told these will fail.

Christchurch mayor Phil Mauger said he and fellow councillors were “outraged” and described it as the council being “forced to chlorinate our water supply.”

To be exempt from chlorination, the council would need to make substantial and expensive upgrades to its water supply network, according to a council statement.

Geoff Butcher and Geoff Mavromatis say new water regulations - and its chlorine requirements - are not needed for their long-running community water schemes. (First published June 2022)

“[E]ven then, it may not be possible,” it said.

Mauger said the city was expected to “go over and above the standards set out by the Government”.

“I feel as a council we have been led up the garden path by Taumata Arowai,” he said.

Mauger has written to the chief executive of Taumata Arowai and requested they attend a public council meeting to explain their position.

Almost 120 well heads have been raised above ground since June 2018 under major efforts to future-proof Christchurch's drinking water network. (First published 2018)

About 20% of the Christchurch City Council’s water supply was chlorine-free, but work began to change that on Tuesday at the arrival of the news.

The remaining 80% is already being treated with a low dose of chlorine (0.2 parts per million).

Most of Christchurch’s water supply has been chlorinated since March 2018 and the council has spent millions upgrading its infrastructure to get rid of the chlorine since then.

Chlorine is a widely used safety measure to prevent contamination and it is required in water supplies across the country.

To get Christchurch’s chlorination levels to zero, it was expected that Taumata Arowai would have to grant an exemption for each of the city’s 11 drinking water supply zones.

To meet legal obligations, staff began work on Tuesday, with chlorine to be reintroduced to the first areas by the end of May.