Auckland Mayor Wayne Brown has called for Watercare and council chief executive Jim Stabback to stop all work on the Government's Three Water reforms, which he says are "doomed".

In a letter to Watercare chairwoman Margaret Devlin he said the previous council and incoming mayor and governing body oppose the reforms.

"In more than 300 campaign events, I detected no support for it at all among Aucklanders. I promised in the election campaign to stop it," he said in the letter.

In a statement issued just after 5pm, Brown said Auckland households are heading into an economic and fiscal storm and Watercare and Auckland Council must keep water charges and rates as low as possible.

Numerous banners opposing Three Waters, like this one in Central Hawke's Bay, appeared during the local body elections. Photo / Neil Reid

"The proposal has not been passed by Parliament and after last weekend's local government elections throughout the country has no chance of proceeding this side of next year's general election.

"It is not in the best interests of Watercare, its shareholder or its customers for it to spend any more money on the doomed proposal – and that is also true of Auckland Council," said Brown.

The new mayor told Devlin he will write to her formally setting out his expectations in relation to a Statement of Intent, but assured her he had no plans for any substantial changes to the council's water business.

Brown has told Devlin and Stabback whatever money they might have spent on the Government-imposed water reforms should be returned to Auckland households in the form of lower water charges and rates than would otherwise be charged."

On the campaign trail, the engineer repeatedly criticised the Three Waters reforms, saying the council's water company, Watercare, is a business that works well.

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"Aucklanders have built and paid for the assets of Watercare. We own them - end of story," he said.

Watercare chairwoman Margaret Devlin. Photo / File

He slammed the Government's decision to model the reforms on Scotland as "just dumb", saying "Scotland has hard rock geology, we have soft rock geology, Scotland has no erosion, we have erosion, Scotland has very simple geography and about four catchments, we have thousands of catchments".

The Herald has sought comment from the council and Watercare.

On election day, Brown said: "Let me be very clear: Wellington's job is to listen to what Aucklanders say are our priorities, and to fund them - not impose ideological schemes like the $30 billion airport tram, untrammelled housing intensification and Three Waters on a city that doesn't want them."

Following the local body elections, Prime Minister Jacinda Ardern said the Government remains "open to changes" to its controversial Three Waters reforms.

While not committing to pausing or reviewing the reforms in any wholesale manner on the Government's watch, Ardern said they will be listening to what comes out of the select committee process and submissions.

The Three Waters programme will take water assets like pipes and reservoirs from 67 councils and amalgamate them into one of four massive water entities.

Prime Minister Jacinda Ardern and Local Government Minister Nanaia Mahuta are under pressure to dump the Three Waters programme. Photo / File

The councils will own these entities through a shareholding but will co-govern them with Māori.

Most of the country's 67 councils had voiced some concern at the reforms even before the local elections, particularly around the governance structure and dilution of local voice.

Some voices have been louder than others, particularly from the 31 members of the three waters opposition group, Communities for Local Democracy.

Brown has also asked Watercare for a briefing on the $1.2 billion Central Interceptor project, saying he has asked for information on any delays in timelines, changes in costs to budgets, and reductions in scope from the original contracts.

A spokeswoman for Local Government Minister Nanaia Mahuta said many councils, including Auckland, had constrained balance sheets.

"This limits Watercare's ability to borrow to invest in this critical infrastructure.

"There are forecasts of a doubling in rates bills for Auckland households if no change is made.

"The Government is committed to keeping a lid on such rates rises to help address cost of living pressures."

The spokeswoman said the Government was committed to making water both safe and affordable, and to upgrading and future-proofing New Zealand's critical infrastructure for the next generation

This included addressing problems with essential water infrastructure and protecting ratepayers from paying thousands of dollars in council rate hikes.