Consultation is under way on a major overhaul of how drinking water, wastewater and stormwater infrastructure and services are delivered across the country.
The government is hosting a series of workshops on its Three Waters reform programme targeted towards informing councils and iwi.
Some 67 different councils own and operate the majority of New Zealand's water services, but that has come under increased scrutiny after a review set up alongside the Havelock North water contamination inquiry found considerable underinvestment in infrastructure and significant ongoing challenges.
The government's early modelling suggested the forward costs of maintaining and improving water services and infrastructure after the years of under-investment could be up to $30 billion to $50 billion above already planned investment over 30 years.
The Three Waters reform programme is aimed to ensure Aotearoa's critical water infrastructure and services are fit for purpose for decades to come.
Three Waters Steering Committee independent chair Brian Hanna said the workshops would explain the government's thinking and seek feedback on a range of potential solutions.
That could include councils handing control of their water services to a small number of publicly-owned, multi-regional entities.
The details of these entities - including their size, shape, design and where they would cover - are still being worked through.
"The primary purpose of the Central/Local Government partnership approach is to ensure that the reform process is informed by the expertise and experience of the local government sector, while also taking account of the expertise and interests of iwi/Māori,'' he said.
Feedback would help to inform official advice to ministers, Hanna said.
The government is expected to release its reform proposals in mid-2021.
By the end of the year, councils and their communities will need to make a call about whether they remain in or opt out of the reform programme.