Three waters reforms will be mandatory for councils as the legislation moves ahead, with working groups to guide the process and take councils' feedback on board, the government has announced.

Currently about 85 percent of storm water, drinking water and wastewater is managed by councils. Some smaller and rural populations, including marae, also get their water through private or community-based providers.

The proposed reforms would move the management of those water assets out of the hands of the country's 67 councils, to four large water entities, with the aim of providing better water services around the country at a lower cost.

Those entities would have boards jointly elected by councils and Māori, and have responsibilities to them, but would be run independently.

The vast majority of councils have expressed some opposition to the reforms and Local Government Minister Nanaia Mahuta has been considering councils' feedback after consultation with the sector closed early this month.

Councils' opposition ranges from concerns about the management model of the entities and calls for the reforms to be delayed, through to total opposition to the legislative changes.

Having considered the feedback, Mahuta today confirmed councils would be required to take part.

"This is an all-in approach that will require legislation and it will require every council to be a part of a quantum shift in the way that water services are delivered.

"The legislation is a mandated decision."

Mahuta announced a technical working group to examine representation and accountability in the three waters model would help guide the process, but the reforms would still go ahead with all entities operational by 1 July 2024.

She said three technical reference groups similar to the Stormwater technical working group would be established that would include iwi, industry and local government experts.

These groups would "help refine the reform proposals with regard to oversight and accountability; rural supplies; and the resource management interface".

An updated timeline includes a promise of ongoing communications with local government, iwi and industry right up until the entities become operational, with select committee processes to take public feedback into account.

National and the Greens have speculated that unless many more councils buy into the reforms, the government could be forced to mandate them.

The government has offered councils various incentives to join the reforms, including funding that would aim to ensure no council is left worse off, but has repeatedly refused to rule out forcing councils into the new arrangement.

Today's announcement leaves that option open should councils remain opposed.

Read more:

• Three waters: What you need to know

Republished by Arrangement