A Māori water rights claim wants to see the country's rivers and lakes treated as public goods instead of a "free lunch" to commercial interests.
The Waitangi Tribunal is this week hearing the closing submissions into a claim over Māori rights to fresh water, following the government decision in 2012 to put shares in state-owned power companies up for sale.
Ownership of water - whether by Māori, nobody, or everybody - has been the focus of a debate around allocation and management issues.
The Waitangi Tribunal and the Supreme Court have both acknowledged Māori have first rights to fresh water, but the government has not supported those findings in policy.
Sir Eddie Durie, chair of lead claimant the New Zealand Māori Council, said their approach was based on a view that "the public owns the water".
The Crown's approach to fresh water was a "failure", placing commercial interests ahead of others, and an Independent Water Commission was needed to reverse the damage, their closing submission said.
They saw three main interests in fresh water: public - which included drinking, sanitation and recreation; Māori customary; and commercial.
"Drinking and sanitation are human rights, and then it is the New Zealand way to be able to swim and fish and the like.
"That sense of 'ownership' is also the basis of the Māori customary interest. For Māori, water as a resource is no less important than land.
"The main food source was historically from the water, plants and trees around the water edge - kahikatea and harakeke - were important for shelter and clothing, and rivers were also the main methods of transport."
But the current freshwater management model, where regional councils administered water under the Resource Management Act, played out in favour of commercial interests.
"The RMA starts on the assumption nobody owns the water so it is free to use, first in, first served.
"People get elected onto councils who have their own private interests, so there is a conflict in the way water is allocated.
"The RMA has become a vehicle for providing a free lunch to commercial interests, such as water bottling companies. Many have derived immense financial wealth from their 'free' water. Those who use it for private commercial benefit should pay for it."
An Independent Water Commission would be made up of half Māori representatives, chosen by Māori, and be funded by charging those who used water commercially.
"Management would be on a catchment by catchment basis, determining sustainable flows in lakes and rivers based on science and ecology. Then allocations would be made for public and customary used, followed by the balance for commercial."
Tāmaki Legal, representing over a dozen iwi and hapū at the hearing, took a stronger stance over water rights, seeking recognition of exclusive Māori rights to fresh water.
Principal Darrell Naden said the way the Crown had managed freshwater and left Māori out of the process was similar to "theft".
"There has been an infringement on Māori rights in water management, and in being shut out of the benefits. It has been the same with other resources that have been nationalised - petroleum, gold, iron sands - without compensation, so in that sense it is theft.
"We are concerned the Crown continues to claim no one owns water, but when we look at the common law, including the Ngāti Apa case in 2003, it is clear Māori can own water."
Ownership models would vary between Māori groups and parts of the country, but Naden said it would be similar to customary title to land.
"That is the base setting on which all reforms should proceed."
What Māori ownership of fresh water would mean for the general population was still to be determined.
"That is a huge question, but we want the Government to recognise native title to fresh water, and then we can sit down and discuss it.
"Our basic concern is environmental, the degradation of waterways, and loss of quality and quantity. So for any ownership interest the primary concern is rejuvenating waterways."
Naden said they did not want to see Māori water rights become the same as the foreshore and seabed issue.
"There is a history of Māori achieving victories in litigation, only to have those cancelled by legislation. That is something we are really concerned about."
Regardless of the Waitangi Tribunal's findings, claims over Māori rights to fresh water would continue to play out in court, Naden said.
The hearing continues to Friday with further submissions including from Te Pou Taiao/Iwi Leaders Forum, and a response from the Crown.
National Fresh Water and Geothermal Resources Inquiry
In March 2012 the Waitangi Tribunal granted an application for an urgent hearing into two claims about Māori proprietary rights in freshwater bodies and geothermal resources.
Wai 2357 is about the Crown's policy to privatise four state-owned power companies without first protecting or providing for Māori rights in the water resources used by the companies.
Wai 2358 is about the Crown's resource management reforms, which the claimants say are happening without a plan to recognise and provide for Māori rights and interests in water.
The inquiry was split into two stages, the first dealing with Māori water rights as at 1840, and the impact of the Crown's proposed sale of shares in State-owned power companies.
The second stage considers if the current laws and reforms in respect of fresh water are consistent with the principles of the Treaty of Waitangi.
This week's hearing in Wellington is the final part of stage two.