Newly released letters mayors wrote to Local Government Minister Nanaia Mahuta show cracks in relations over the Three Waters reform appeared months before it was mandated.

The letters obtained through an OIA include calls to pull a government advertising campaign and complaints from councils about the speed and the way the process had been handled.

Papers released last month revealed Cabinet had agreed in June to pursue an "all-in legislated" reform strategy, knowing that achieving the benefit of reforms would, in practice, require eliminating the possibility of opting out.

Mahuta had consistently refused to rule out making the reforms mandatory, but did not confirm the move until late October.

Twenty-four councils are now nationally fighting the government's Three Waters mandating through the Communities 4 Local Democracy campaign.

The Three Waters ad campaign

On June 28, the chairs representing South Island councils, Selwyn Mayor Sam Broughton and Clutha Mayor Bryan Cadogan, wrote to the minister requesting an "immediate cessation" of its public information campaign of the reform.

The ad campaign depicts unhappy cartoon people and animals with poor quality water.

The two mayors say the tone and theme of the adverts totally trivialised and wrongly portrayed the situation.

"We now find a concerted effort is underway to present an untruthful paradigm where local government is undermined with inflammatory statements that are detached from reality," they say.

In a response, Mahuta defended the adverts.

"The animated approach was chosen to achieve maximum cut through in a space crowded with issues calling for New Zealanders' compassion and care and it translates easily across different demographics, from age groups to ethnicities. It takes a quirky approach to a dry and difficult subject matter," she wrote.

She says their letter had taken her by surprise.

"The campaign is not intended in any way to denigrate local government in its stewardship of our three waters services. To date officials have not had any indications from the general public, at whom it is aimed, that the campaign has been interpreted in this way," she says.

Christchurch Mayor Lianne Dalziel also wrote to the minister, supporting her colleagues' views. Photo: RNZ / Nate McKinnon.

However, on July 2 Christchurch Mayor Lianne Dalziel described the adverts as "patronising, inaccurate, scare-mongering and borders on prejudicial stereotyping".

"I am aware that several of my colleagues have since raised this with you. I have seen your reply to Mayors Broughton and Cadogan, which unfortunately misses the mark when it comes to the television advertisement potentially breaching the trusted relationship we have built up with you," she said.

Dalziel said she had reflected on whether to lodge a complaint with the Advertising Standards Authority.

A total of 48 complaints were made about the adverts, but the ASA ruled in the context of advocacy advertising that it was not misleading or offensive.

Warnings to slow down or pause the Three Waters process

On August 24, West Coast mayors wrote to the minister urging her to give them more time.

"There is major concern on the West Coast around the reform and how it will affect our communities and this important decision needs to be fully informed," they said.

"While many questions remain unanswered, we would like more time to understand the implications for our communities and engage with them meaningfully."

Grey District Mayor Tanai Gibson, Westland District Mayor Bruce Smith and West Coast Regional Council chair Allan Birchfield expressed their concern about the uncertainty around Taumata Arowai's role and the powers of the new Economic Regulator.

"Therefore, we would like to see an immediate pause in the reform process to allow councils to consider the points raised and to be able to engage effectively with our communities," they said.

In September, Mahuta was warned by Waipa Mayor Jim Mylchreest of the "growing disquiet" within the local government sector.

"I would have to include myself in the group of mayors who have concerns over the speed and direction of the proposed reforms and the negative impact they are likely to have on our communities," he said.

He said feedback from the community was almost universally opposed to the reforms as proposed and he feared that if they proceeded in the current format there would be a significant political consequence.

"The demands I am receiving are for full public consultation and preferably a referendum on the matter. The results of this consultation will inevitably result in a large number of councils resolving to opt out of the reforms," he said.

-RNZ/Katie Doyle/Charlie Dreaver.